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Generic Viagra is a drug used for erectile dysfunctions, or male impotence, and it represents the name for a substance known as sildenafil citrate. The substance is the same, while the market name of the drug may vary and so may its price. Generic versions for many types of drugs have been around for quite some time, but Generic Viagra is a fairly new drug on the market, and it gives men a chance at treating their erectile dysfunctions in an affordable way. Generic Viagra can be expected to have the same effects that the brand name Viagra does, because both drugs have the same active ingredient. Therefore, if your doctor has decided that Viagra is safe for you, it means that you can also use Generic Viagra. How does Generic Viagra work? It increases your ability to have and sustain an erection by inhibiting the enzymes that degrade the cyclic guanosine monophosphate, a substance that facilitates the influx of blood into the penis, by relaxing its spongy tissue. In other words, Viagra dilates blood vessels in the penis, and allows the necessary inflow of blood that an erection requires. Viagra can cause erections only when a man is sexually excited. This is the reason why this drug is not for regular use. It should be taken about one hour before sexual activity, and once the sexual intercourse is over the erection goes away. The efficacy of Generic Viagra has been evaluated based on self-assessment questionnaires, and this evaluation has shown that this drug is responsible for the sexual function improvement of almost ninety percent of those who have used it to treat their erectile dysfunctions. The evaluation included firmness, frequency, and ability to maintain an erection; level and frequency of desire; frequency of orgasm; sexual intercourse satisfaction; and relationship satisfaction. When it comes to the side effects that Generic Viagra can have, it is difficult to anticipate them. Your doctor should be informed shortly after the development of a side effect has occurred, or it has changed its intensity. Some of the side effects of Generic Viagra that are more likely to be experienced by those who use it as treatment include headache, abnormal vision, diarrhea, indigestion, urinary tract infection, and nasal congestion. There are other possible side effects, but these have been experienced at a considerably lower frequency. Remember that it is hard to predict how your body will react to this drug. Chances are that you’ll be just fine, if you don’t have a preexisting condition, such as a heart problem. However, you should inform your doctor about any modification that may occur, and he/she will tell you whether or not you should keep taking Generic Viagra. It is the doctor once again that will give you the most detailed information about the food and drugs Generic Viagra interacts with. It is a well-known fact that erectile dysfunction drugs should not be used simultaneously unless prescribed by a doctor. However, Generic Viagra may interact with other drugs as well, which is why you have to consult with your doctor before taking this medicine. He or she will also inform you about the special warnings that come with this medication, and what conditions do not allow the use of Generic Viagra. generic price viagra Dietary supplements marketed to provide male sexual enhancement contain undeclared erectile dysfunction drugs putting users at risk, the Food and Drug Administration warned Friday. The agency advised consumers to stay away from Shangai Chaojimengnan supplements sold under the names Super Shangai, Strong Testis, Shangai Ultra, Shangai Ultra X, Lady Shangai and Shangai Regular. The Chinese-made supplements are packaged and distributed by Shangai Distributor Inc. of Puerto Rico. Product testing indicates that some of these so-called supplements contain Viagra's active ingredient, sildenafil, or a compound with a chemical structure that mimics sildenafil. These chemicals could interact with nitrates in drugs taken for disorders commonly associated with erectile dysfunction, including diabetes, high blood pressure, high cholesterol and heart disease. The result could dangerously lower a user's blood pressure, according to the FDA. The agency also warned that the safety and purity of these illegal ingredients is unknown..
When we speak of sex drive problems, or dysfunction, we automatically think of males and erectile dysfunction, and omit women from the equation. however, many women experience problems with their �libido' or sexual energy, and this phenomena deserves attention too. viagra is the most common treatment for erectile dysfunction in males, and has traditionally been recommended for men only, women being advised not to use it. so the main reason for this is lack of empirical research stating otherwise, which is due to the absence of definitive studies on women. viagra however can work for women, as it increases the blood flow to a woman's genitals (much the same way as with a man's), which boosts their libido. there are important considerations however, which shall be listed below. as viagra is aimed at men's erectile dysfunction, women are unable to obtain a prescription and buy viagra from a pharmaceutical store. however generic versions are available on the internet, but as so many are on the market, if in doubt contact the supplier as to whether a product is available. when buying from online pharmacies, it is possible to check their pharmacy id if concerned about legitimacy. it is important for women to take into consideration possible side effects of viagra, although not widespread there is still a possibility of them occurring. for instance, some viagra users have reported dizziness, flushing, loss of vision, and so on. check all possible side effects before commencing use. furthermore, viagra should not be taken alongside any nitrate medicines as this can cause abnormally low blood pressure, so always check! women, who suffer with a low sex drive often, should seek a long term cure other then viagra in order to increase their libido and have a permanent effect. long term viagra use can result in expense, so if the problem continues regularly, even after viagra use, women should aim to seek other remedial methods. If you become dizzy or nauseated, have pain, numbness or tingling in your chest, arms, neck, or jaw during sex, it is of the utmost importance that you stop and call your doctor immediately. You could be having a serious side effect from taking Cialis. Stop using Cialis and get emergency medical assistance from your health provider if you have sudden vision loss. It is also advisable that you get immediate medical assistance if you have any of these signs of an allergic reaction: hives, difficulty breathing, or swelling of your face, lips, tongue, or throat. Chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling Swelling in your hands, ankles, or feet Erection that is painful and lasts for around 4 hours. Warmth or redness in your face, neck, or chest Headache, upset stomach and back pain Tadalafil was administered to over 5,700 men (mean age 59, ranging from 19 - 87 years old) during clinical trials all round the world. In this trial, over 1000 patients were treated for 1 year whereas over 1,300 patients were treated for 6 months or more. In placebo controlled, Phase 3 clinical trials, the discontinuation rate because of adverse events in patients treated with tadalafil 10 or 20 mg was 3.1%, which was significantly less than placebo treated patients. In tadalafil clinical pharmacology trials, back pain normally occurred 12 - 24 hours after dosing and often resolved within a mater of two days. Across all research with any tadalafil dose, findings of changes in color vision were rare. Serious cardiovascular issues, including myocardial infarction and sudden cardiac death have been reported post marketing with the use of tadalafil. Many, but not all, of these patients had pre-existing cardiovascular risk issues. Most of these events were reported to occur during or shortly after sexual routine, and some were reported to occur shortly after the use of Cialis. Other adverse events suffer from a lack of clear alternative causation because these reactions were reported voluntarily from a population of uncertain size. This makes it tough to reliably judge their frequency or come up with a causal relationship to drug exposure

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Viagra Professional is a new generation extra-strength prescription medicine that is taken orally for the treatment of erectile dysfunction only in men, powerfully activating the natural blood flow, followed by hardness and expansion of your sexually excited penis for peak sexual performance. Nowadays, erectile dysfunction can be safely and effectively treated. Oral Viagra Professional is one of the most refined and individualized forms of erectile dysfunction treatment. Carefully formulated and clinically tested, Viagra Professional will improve your sexual relationship with your partner in any case. Taking Viagra Professional about 15 minutes to 20 minutes before your sexual intercourse will help you get a most powerful erection ever, the desire will appear overwhelming, and you will feel rejuvenated. You will not need so much stimulation like before; just a touch will bathe you into the ocean of sexual fantasies buy viagra online in uk There is no foolproof evidence of Viagra not working on women, but according to research carried out on 577 women who had issues with sexual arousal for a time period of at least six months, it has been established that Viagra is not very effective in women. This is because sexual difficulties in women are complex in nature. The women took 10, 50 or 100 milligrams of Viagra one hour before sex for three months. The researchers came to the conclusion that Viagra did not make any sort of difference in terms of greater sexual arousal even though Viagra does enhance blood flow to the woman's genital portion. People are of the view that Viagra does not work on women because they are altogether different from man in terms of their objectives, desires, emotions and at the biochemical level. Female sexuality is quite complex compared to male sexuality so even after wide array of scientific research involving about 3,000 women, Pfizer has not been able to come up with authentic findings. Not so long ago, Pfizer publicly announced in the media that they are completing research of Viagra in women. That does not mean there is no any ray of hope for women. Research is going on continuously in a number of other products for the female libido. Research on postmenopausal women on Viagra has come to the conclusion that the Viagra did have some bearing on the blood flow to the clitoris (quite a number of times uncomfortably so) but did not assist any of the women in getting aroused or feeling more at ease during sex. The multicenter research, which was conducted in Canada, various cities of Europe, and Australia, consists of pre-menopausal and postmenopausal women who have opted for hormone replacement therapy and have been diagnosed with female sexual arousal disorder, a category that falls under the broad umbrella of sexual dysfunction. Interestingly, around twenty eight percent 28% of the women reported hypoactive sexual desire disorder as the main symptom. 17% of the women complained of female orgasmic disorder. 9% women were facing issues due to dyspareunia. A wide array of sexual complaints may have played a prominent role in watering down the effectiveness of Viagra. Only a small chunk of women suffering with sexual dysfunction have poor genital feedback without any issues involving libido or mental arousal. Yet those are the sorts of patients who should get an advantage from taking Viagra. That is where future research will study subgroups of women with arousal disorder, especially those who suffer difficulty in getting extra blood to the front portion of the vagina during sex. viagra cialis levitra WSJ's Health Blog offers news and analysis on health and the business of health. The lead writer is Jacob Goldstein. He came to The Wall Street Journal from the Miami Herald, where he was a medical writer. Scott Hensley, who covered the drug industry as a reporter for the Journal for seven years, is the editor and also a contributor. The blog also includes contributions from other staffers at the Journal, WSJ.com and Dow Jones Newswires. Write to us at . Message copied & clipped from an e-mail we recieved from a more than happy customer. Wow what can I say… an amazing experience. In August a couple of my friends and I had planned to go on a short break to Amsterdam to unwind from stress and worries of our normal lives. We already had lots of things planned to do while we were there but once we arrived we were suprised to see one of our mates had brought along ). I personally hadn’t tried this stuff before, but I was always anxious when joining a female in the ‘bedroom department’ just incase I under performed so the thought of buying viagra or a viagra alternative had always crossed my mind but I just simply didn’t get around to it. This made me quite excited to use it. On the second night of being there, our mate suggested for us to go to a strip bar and as you can imagine we hit bar after bar and ended up in you know where. My mate pulled out the strip of kamagra jellys and we got down to business! My friend who brought the kamagra originally gave me your website address so I could buy some more at a later date. So I decided to e-mail you guys with a short story of my experience of generic viagra. Oh and yes, the sex was amazing!

A consistent inability to sustain an erection sufficient for sexual intercourse. Also commonly known as impotence. Medically, the term erectile dysfunction is used to differentiate impotence from other problems that interfere with sexual intercourse The following drugs and medications are in some way related to, or used in the treatment of Impotence. This service should be used as a supplement to, and NOT a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners.free viagra A sexual disorder is defined as the inability to enjoy sexual intercourse or having problems in the sex life. A person has difficulty in having or enjoying sex because of these disorders. It does not make any difference in the physical health but it can affect mental state by bringing on panic attacks, anxiety and feelings of depression. Sexual disorders occur in both men and women. It is not easy to diagnose a person with a sexual disorder because not everyone interested in sexual intercourse all the time. Some may not be interested in having sex at all and some have a lower level of desire or sexual need. If there are no symptoms of depression, no relationship problem, but still no interest in sex then, it can be classified as a sexual disorder. Consulting your doctor is the first best step in identifying a sexual disorder. These disorders are quite common and create lot of stress because people feel uncomfortable talking about sexual disorders, even to their doctors. Sexual activity needs comfortable environment, concentration and relaxation. Depending on the cause of sexual disorder, there are various treatments. If it is a physical problem, medication and different therapies can be done. If it is a psychological cause, it is best to consult with sexologists. Sexologists use different therapies to produce interest in sex. Psychotherapies can also be beneficial in this regard. Relationship therapists deal with relationship problems and stress, which may be the cause of the sexual disorder. Vasodilators, Minoxidil, Yohimbine Therapy Looking at the psychology of impotence is comparable to taking a trip down the Amazon during the rainy season. It is a topic fraught with hidden currents, treacherous shallows and wide meanderings. Viagra, the little blue pill has given a new life to the treatment of impotence and has a significant bearing on men who are suffering from erectile dysfunction. It is worth noting that just finding a "quick fix" for impotence does not overcome other issues that may have been the cause of the dysfunction before treatment began. Overcoming impotence often gives men unrealistic expectations about their ability to instantly come over their emotional as well as physical problems. For most men, their ability to get an erection and have sex is considered as a important part of their masculinity and potency. It is no surprise that the onset of impotence, even when due to underlying physical condition, can lead to psychological issues that increase the problem of impotence. Generally speaking, performance anxiety is a very real problem for many men. In other words, the fear of not being able to perform, dissatisfaction with penis size and self-consciousness about body appearance can all lead to the thing that most men do not want even in their dreams: failure to get an erection. Most men have an occasional episode of impotence due to anxiety. If erectile dysfunction has been there for considerable amount of time, this anxiety is multiplied. From a physiological point of view, anxiety can effectively prevent a man from becoming aroused and maintaining an erection. All the psychological issues seem to disappear with the help of Viagra, which is why it is the most effective and most prescribed erectile dysfunction treatment on the market. There is no reason to feel awkward if you are having issues getting an erection. Just remember that erectile dysfunction is a common problem and can happen to anyone of any age. When you take Viagra for the first time it provides harder erections and plays a prominent role in maintaining the erection for a longer period of time during sex. As Viagra has been proven safe to use in men who are suffering from heart problems, high cholesterol, diabetes, high blood pressure, prostate problems as well as spinal injury you feel at ease when using it. The best part about Viagra is that it works when you want it to. Studies have shown that it works for most men in as little as fourteen minutes, on average within half an hour, and makes it’s presence felt for at least four hours. sildenafil pulmonary hypertension clinical study Used to treat male erectile dysfunction will not be subsidized by the state, Sweden's Supreme Administrative Court ruled on Friday. and Bayer Schering Pharma slammed the ruling, arguing that half a million Swedish men would be affected by the decision not to subsidize drugs such as Viagra, Cialis and Levitra. In its ruling the court overturned a four year old decision by the County Administrative Court to help cover the costs of Viagra and Cialis for patients suffering from high blood pressure or diabetes, both of which often lead to problems with impotence. "The verdict is deeply unjust for many Swedish men and their partners who suffer as a result of impotence," said Margareta Nilsson, chairwoman of the Swedish Diabetes Association, in a statement. "The decision means that this will become a class issue as those affected will have to finance their own treatment in order to have a functioning sex life," she added. The Supreme Administrative Court said in its ruling that the lack of specialist physicians in many parts of the country made it difficult to make a diagnosis. As such, there was a clear risk that a disproportionate number of patients would be prescribed with the drugs. When we speak of sex drive problems, or dysfunction, we automatically think of males and erectile dysfunction, and omit women from the equation. However, many women experience problems with their â€?libido' or sexual energy, and this phenomena deserves attention too. Viagra is the most common treatment for erectile dysfunction in males, and has traditionally been recommended for men only, women being advised not to use it. So the main reason for this is lack of empirical research stating otherwise, which is due to the absence of definitive studies on women. Viagra however can work for women, as it increases the blood flow to a woman's genitals (much the same way as with a man's), which boosts their libido. There are important considerations however, which shall be listed below. As Viagra is aimed at men's erectile dysfunction, women are unable to obtain a prescription and buy Viagra from a pharmaceutical store. However generic versions are available on the internet, but as so many are on the market, if in doubt contact the supplier as to whether a product is available. When buying from online pharmacies, it is possible to check their pharmacy ID if concerned about legitimacy. It is important for women to take into consideration possible side effects of Viagra, although not widespread there is still a possibility of them occurring. For instance, some Viagra users have reported dizziness, flushing, loss of vision, and so on. Check all possible side effects before commencing use. Furthermore, Viagra should not be taken alongside any nitrate medicines as this can cause abnormally low blood pressure, so always check! Women, who suffer with a low sex drive often, should seek a long term cure other then Viagra in order to increase their libido and have a permanent effect. Long term Viagra use can result in expense, so if the problem continues regularly, even after Viagra use, women should aim to seek other remedial methods. As effective than the normal, if not better. Non-prescription drug, buy generic viagra over the Internet. Although generic viagra is not an FDA approved drug, it is manufactured by Ajanta Pharma in India a reputable pharmacy company who has being making popular generic drugs since 1990. One thing to do before buying generic viagra over the Internet, is to check phone numbers and contact details on the suppliers website. If something looks fishy, don’t even go there! Click here to on our website today for an excellent experience! bingo buy game online viagra Should I Confront My Wife About Affair? TEN years ago I fell in love with a girl. She was 22 years younger than me and I was married. But the love I felt for her then - and still do - was overwhelming. So I left my wife for her. It was messy and my two grown-up children made it clear they wanted nothing to do with me after what I had done to their mum. I felt guilty but the dust settled and after the divorce I married my second wife. It was the happiest day of my life. We now have an eight-year-old and I've managed to patch things up with the older ones. My wife is 37 and I'll be 60 this year. The problem is I have been having trouble sustaining an erection. I'm taking Viagra which helps, but I don't have the same energy I used to have. I'm almost certain my wife is having an affair. We had a young guy, in his twenties, help get the garden in our new house into shape and I could see he was attracted to her. She's still an amazing-looking woman and doesn't look a year older than when I first saw her. She's been getting texts which she deletes immediately and I know for a fact when she told me she was round at her mum's that it was a lie. So I'm worried sick. I know I should tackle her about what's going on but I can't. I can't live without her and I don't like the thought of my ex-wife, most of my friends and my relatives pointing out that they all told me the age gap was too big and we wouldn't last. OF course you could carry on as you are with your head buried in the sand. There is the possibility your wife isn't having an affair or even if she is, it isn't serious and will soon blow itself out. Your problem keeping an erection could be affecting self-confidence and putting your imagination into overdrive. In some ways, sitting tight might be the sensible thing to do, especially as you have a young child but no intention of ending the marriage. But I don't think you can live with the uncertainty forever. Maybe you should give yourself a deadline of a few months. If you remain suspicious or get more solid evidence, I don't believe you can go on ignoring the issue. If she wants to save the marriage, counselling through Relate Scotland or Scottish Marriage Care is the next step. But if things can't be fixed, there's no point trying to glue it together just because you don't want those who warned you against marrying a younger woman crowing. If you have a problem, write to: Just Joan, Daily Record, One Central Quay, Glasgow G3 8DA or email j.burnie@dailyrecord.co.uk. I cannot reply personally.  sildenafil citrate soft tab Levitra and Viagra are different drugs used to treat one common issue, Erectile Dysfunction (impotence). There are lots of similarities as well as differences when looking at Levitra vs. Viagra. Advice from your health care provider is the ideal way to conclude which drug is the perfect choice for treating your ED. One should never diagnose and treat ED on their own; it could turn out to be a life threatening move. It is mandatory for men with ED to understand the fact that they are not alone. As a matter of fact, millions of men all over the world suffer from ED each year. Fortunately, advancement in pharmaceutical technology has offered choices for these millions. When comparing Levitra with Viagra, the main point of difference is the main ingredient. While Levitra’s main ingredient consists of vardenfil, a PDE5 inhibitor, the main ingredient in Viagra is sildenafil citrate, which has been used not only to treat ED, but also pulmonary arterial hypertension Side effects arising from the use of vardenfil are: abdominal pain, back pain, photosensitivity, abnormal vision, eye pain, facial edema, hypertension, palpitation, tachycardia, arthralgia, myalgia, rash, itch, priapism, and in a few rare scenarios heart attack. Vardenfil should also not be taken if the patient is using any sort of nitrate medication. This is because it has the tendency to produce very low blood pressure. Health care providers will never prescribe Levitra to a patient at risk of experiencing serious side effects. Viagra was the first pill to be introduced to the market. Side effects of Viagra include: priapism, severe hypotension, myocardial infarction, ventricular arrhythmias, sudden death, stroke and enhanced intraocular pressure. The common side effects consist of sneezing, headache, flushing, dyspepsia, prolonged erections, palpitations, and photophobia. Visual changes including blurring of vision and a curious bluish tinge which have been reported in studies. Levitra and Viagra are nearly identical in that they are to be consumed anywhere from a half an hour to a couple of hours prior to sexual activity. Viagra may have been the starting point in the treatment of ED, but there is no doubt that Levitra has been seen as “new and better”. Levitra’s side effects are far and few versus Viagra, though response of drugs varies from person to person. A detailed analysis of your medical history is required to choose the ideal prescription drug for you.

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Should I Confront My Wife About Affair? TEN years ago I fell in love with a girl. She was 22 years younger than me and I was married. But the love I felt for her then - and still do - was overwhelming. So I left my wife for her. It was messy and my two grown-up children made it clear they wanted nothing to do with me after what I had done to their mum. I felt guilty but the dust settled and after the divorce I married my second wife. It was the happiest day of my life. We now have an eight-year-old and I've managed to patch things up with the older ones. My wife is 37 and I'll be 60 this year. The problem is I have been having trouble sustaining an erection. I'm taking Viagra which helps, but I don't have the same energy I used to have. I'm almost certain my wife is having an affair. We had a young guy, in his twenties, help get the garden in our new house into shape and I could see he was attracted to her. She's still an amazing-looking woman and doesn't look a year older than when I first saw her. She's been getting texts which she deletes immediately and I know for a fact when she told me she was round at her mum's that it was a lie. So I'm worried sick. I know I should tackle her about what's going on but I can't. I can't live without her and I don't like the thought of my ex-wife, most of my friends and my relatives pointing out that they all told me the age gap was too big and we wouldn't last. OF course you could carry on as you are with your head buried in the sand. There is the possibility your wife isn't having an affair or even if she is, it isn't serious and will soon blow itself out. Your problem keeping an erection could be affecting self-confidence and putting your imagination into overdrive. In some ways, sitting tight might be the sensible thing to do, especially as you have a young child but no intention of ending the marriage. But I don't think you can live with the uncertainty forever. Maybe you should give yourself a deadline of a few months. If you remain suspicious or get more solid evidence, I don't believe you can go on ignoring the issue. If she wants to save the marriage, counselling through Relate Scotland or Scottish Marriage Care is the next step. But if things can't be fixed, there's no point trying to glue it together just because you don't want those who warned you against marrying a younger woman crowing. If you have a problem, write to: Just Joan, Daily Record, One Central Quay, Glasgow G3 8DA or email j.burnie@dailyrecord.co.uk. I cannot reply personally.

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Viagra is one of the few prescription drugs that require almost no publicity. You can find news stories, detailed description and jokes in print, on television and on the internet. Sexual dysfunction is a very serious issue for those who are suffering as well as for their partners. After years without the ability to enjoy sexual intimacy, it is no surprise that lots of people all over the globe are ready to try Viagra. Though the drug that is capable of restoring penile erectile functions, it has wide array of medical, economic and social problems attached. Older users with severe heart disease may experience side effects which can lead to death and the chemical effects of Viagra are also life threatening. Additionally, adverse social effects of Viagra use have also come into the fray in various media circles. There are newspaper reports that say the lives of older couples are being ruined because of Viagra. Men are leaving longstanding relationships for younger women and there are cases of assault on women because of their lack of response to a partner’s new sexual routine. The normal dose of Viagra is 50 mg taken about an hour prior to the expected sex act, though the medication is effective even if taken four hours prior to sex. It is of paramount importance that the next dose not be used until after a day has passed from the last intake. Most importantly, patients with liver or kidney disease should take lower dosages (25 mg) due to their lower ability to eliminate the drug. The most basic reactions with the use of Viagra are headaches, flushing, indigestion and nasal congestion. These sorts of reactions occur in 4% - 16% of patients taking Viagra. Most of the adverse reactions are mild in nature and quite well handled by healthy individuals. While it cannot be termed as an adverse reaction, the new-found sexual prowess can lead older males with underlying medical issues such as heart disease to exert themselves more than they have in recent years. This can precipitate a heart attack or other acute medical emergency. According to one study, the Food and Drug Administration has reported sixteen deaths that followed the use of Viagra. All of these deaths occurred in individuals sixty years and older suffering from of heart disease, hypertension or diabetes. The use of Viagra may lead to stress and marital discord which can result in divorce and the need for psychological counseling. Apart from that, the enhanced sexual routine may also give rise to sexually transmitted diseases and AIDS in older individuals who would not normally be exposed. When we speak of sex drive problems, or dysfunction, we automatically think of males and erectile dysfunction, and omit women from the equation. However, many women experience problems with their â€?libido' or sexual energy, and this phenomena deserves attention too. Viagra is the most common treatment for erectile dysfunction in males, and has traditionally been recommended for men only, women being advised not to use it. So the main reason for this is lack of empirical research stating otherwise, which is due to the absence of definitive studies on women. Viagra however can work for women, as it increases the blood flow to a woman's genitals (much the same way as with a man's), which boosts their libido. There are important considerations however, which shall be listed below. As Viagra is aimed at men's erectile dysfunction, women are unable to obtain a prescription and buy Viagra from a pharmaceutical store. However generic versions are available on the internet, but as so many are on the market, if in doubt contact the supplier as to whether a product is available. When buying from online pharmacies, it is possible to check their pharmacy ID if concerned about legitimacy. It is important for women to take into consideration possible side effects of Viagra, although not widespread there is still a possibility of them occurring. For instance, some Viagra users have reported dizziness, flushing, loss of vision, and so on. Check all possible side effects before commencing use. Furthermore, Viagra should not be taken alongside any nitrate medicines as this can cause abnormally low blood pressure, so always check! Women, who suffer with a low sex drive often, should seek a long term cure other then Viagra in order to increase their libido and have a permanent effect. Long term Viagra use can result in expense, so if the problem continues regularly, even after Viagra use, women should aim to seek other remedial methods. A Revolution of any sort brings with it a new way a life. Viagra, the little blue bill developed for the treatment of erectile dysfunction (ED) has led to a new sexual revolution. This sexual revolution has brought with it a radical change in terms of sexual morality as well as behaviour all around the globe. This is not just another drug; it is the magic bullet that people have been waiting a long time for. Blame it on their nature, men are whimsical creatures who have big egos more and adjudicate their performance on the basis of their sexual prowess. That is where, when men loose their control over sexual ability, they tend to lose their self control. If a man is suffering from ED he is not going to discuss his sex life with anyone, not even with his health care provider. He may even feel embarrassed to talk about it with his mate. Thanks to Viagra, impotence is no longer a taboo issue. Believe it or not, men are coming up openly to discuss and correct their sexual ailment. The sexual revolution attached with Viagra has changed the whole attitude of men’s towards sexuality. With the assistance of Viagra, men are confident that they can satisfy their partner with ease. All in all, their sexual behavior has become more progressive and adventurous. Viagra can restore virility in about 80% of men who have issues, with only minor side effects such as headaches and indigestion. Older medical treatments can leave men with erections that last for more than four hours if sex does not take place. The best part about Viagra is that it only becomes effective when a man is sexually aroused. The drug start making its presence felt when it blocks the operation of an enzyme that plays a prominent role in breaking down the chemical cyclic GMP which is quite important in maintaining erections. Normally, Viagra assisted erections subside after intercourse, a few men have reported that the drug can remain effective for a day. There is no denying that Viagra is fulfilling the requirements of millions of men all around the globe who are suffering from erectile dysfunction by offering them an opportunity to regain their sex lives and lighten up their low self esteem. It assists in infusing freshness in a stale relationship, is a ray of hope for millions of sexually dissatisfied people and has the ability to redefine the meaning of sex and sexuality in your mind and body.

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Treating high blood pressure in the lungs (pulmonary arterial hypertension [PAH]). It may also be used for other conditions as determined by your doctor. Revatio is a phosphodiesterase inhibitor. It works by relaxing blood vessels in the lungs, which decreases blood pressure. you are taking nitrates (eg, isosorbide, nitroglycerin) in any form (eg, tablet, capsule, patch, ointment), nitroprusside, or ritonavir you use certain recreational drugs called "poppers" (eg, amyl nitrate, butyl nitrate) Contact your doctor or health care provider right away if any of these apply to you. Some medical conditions may interact with Revatio . Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you: if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement if you have allergies to medicines, foods, or other substances if you have blood problems (eg, sickle cell anemia, leukemia, multiple myeloma), a deformed penis (eg, Peyronie disease, cavernosal fibrosis), or any other condition that may increase the risk of a prolonged erection (eg, priapism) if you have a history of certain eye problems (eg, retinitis pigmentosa, sudden vision loss, optic neuropathy, macular degeneration) if you are dehydrated or have a history of liver or kidney problems, high or low blood pressure, ulcers, bleeding problems, heart problems (eg, heart failure, irregular heartbeat, aortic stenosis, angina), blood vessel problems, or nervous system problems if you have a history of heart attack, stroke, or life-threatening irregular heartbeat, especially within the past 6 months Some MEDICINES MAY INTERACT with Revatio . Tell your health care provider if you are taking any other medicines, especially any of the following: Alpha-blockers (eg, doxazosin), amlodipine, medicines for high blood pressure, nitrates (eg, isosorbide, nitroglycerin), or nitroprusside because severe low blood pressure with dizziness, lightheadedness, and fainting may occur Warfarin because the risk of bleeding, especially nosebleed, may be increased Azole antifungals (eg, itraconazole), cimetidine, H2 agonists (eg, famotidine), HIV protease inhibitors (eg, ritonavir), macrolide antibiotics (eg, erythromycin), or telithromycin because they may increase the risk of Revatio 's side effects Barbiturates (eg, phenobarbital), bosentan, carbamazepine, efavirenz, nevirapine, phenytoin, rifabutin, or rifampin because they may decrease Revatio 's effectiveness This may not be a complete list of all interactions that may occur. Ask your health care provider if Revatio may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine. Use Revatio as directed by your doctor. Check the label on the medicine for exact dosing instructions. An extra patient leaflet is available with Revatio . Talk to your pharmacist if you have questions about this information. Take Revatio by mouth with or without food. Take your doses 4 to 6 hours apart unless your doctor tells you otherwise. Take Revatio on a regular schedule to get the most benefit from it. Take it at the same times each day. Continue to take Revatio even if you feel well. Do not miss any doses. If you miss a dose of Revatio , take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once. Ask your health care provider any questions you may have about how to use Revatio . Dizziness may occur while you are using Revatio . This effect may be worse if you take it with alcohol or certain medicines. Use Revatio with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it. Patients with heart problems who take Revatio may be at increased risk for heart-related side effects, including heart attack or stroke. Symptoms of a heart attack may include chest, shoulder, neck, or jaw pain; numbness of an arm or leg; severe dizziness, headache, nausea, stomach pain, or vomiting; fainting; or vision changes. Symptoms of a stroke may include confusion, vision or speech changes, one-sided weakness, or fainting. Contact your doctor or seek medical attention right away if you experience these symptoms. Revatio may rarely cause a prolonged, painful erection. This could happen even when you are not having sex. If this is not treated right away, it could lead to permanent sexual problems such as impotence. Contact your doctor right away if this happens. If vomiting or diarrhea occurs, you will need to take care not to become dehydrated. Contact your doctor for instructions. Use Revatio with caution in the ELDERLY; they may be more sensitive to its effects. Revatio should be used with extreme caution in CHILDREN; safety and effectiveness in children have not been confirmed. PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Revatio while you are pregnant. It is not known if Revatio is found in breast milk. If you are or will be breast-feeding while you use Revatio , check with your doctor. Discuss any possible risks to your baby. All medicines may cause side effects, but many people have no, or minor, side effects. If any of the following most COMMON side effects continue or become bothersome, check with your doctor: Diarrhea; dizziness; flushing; headache; muscle aches; nosebleed; numb or tingling skin; stuffy nose; trouble sleeping; upset stomach. Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chest pain; confusion; fainting; fast or irregular heartbeat; fever; numbness of an arm or leg; one-sided weakness; painful or prolonged erection; ringing in the ears; seizure; severe or persistent dizziness or nosebleed; severe or persistent vision changes; shortness of breath; speech problems; sudden decrease or loss of vision in one or both eyes; sudden hearing loss. This is not a complete list of all side effects that may occur. If you have questions or need medical advice about side effects, contact your doctor or health care provider. You may report side effects to the FDA at 1-800-FDA-1088 (1-800-332-1088) or at . Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center ( ), or emergency room immediately. Symptoms may include fainting; prolonged erection; severe dizziness. Store Revatio at room temperature at 77 degrees F (25 degrees C). Brief storage at temperatures between 59 and 86 degrees F (15 and 30 degrees C) is permitted. Store away from heat, moisture, and light. Do not store in the bathroom. Keep Revatio out of the reach of children and away from pets. If you have any questions about Revatio , please talk with your doctor, pharmacist, or other health care provider. Revatio is to be used only by the patient for whom it is prescribed. Do not share it with other people. If your symptoms do not improve or if they become worse, check with your doctor. This information is a summary only. It does not contain all information about Revatio . If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

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Drug Cialis for daily use. in 2003, and in 2007 alone they had a wopping figure of $798 million although this year it is expected to top over $1 billion in sales. They will report the official sale figures year-end January 29th. The once-a-day version will be marketed to men who anticipate having sex two or more times a week, without confining it to a limited time frame. When Cialis is taken daily, men can attempt sexual activity at any time. The low-dose daily version of the drug already is available in parts of Europe, Lilly said. Neither Viagra nor Levitra, a pair of competitors, is sold in once-daily doses. Althought Cialis maybe aggressively approaching the market with a new idea, was founded five years before Cialis company, and remains to be the most branded and popular erectile dysfunction drug in the World!buy online phentermine valium viagra xanax Used to treat male erectile dysfunction will not be subsidized by the state, Sweden's Supreme Administrative Court ruled on Friday. and Bayer Schering Pharma slammed the ruling, arguing that half a million Swedish men would be affected by the decision not to subsidize drugs such as Viagra, Cialis and Levitra. In its ruling the court overturned a four year old decision by the County Administrative Court to help cover the costs of Viagra and Cialis for patients suffering from high blood pressure or diabetes, both of which often lead to problems with impotence. "The verdict is deeply unjust for many Swedish men and their partners who suffer as a result of impotence," said Margareta Nilsson, chairwoman of the Swedish Diabetes Association, in a statement. "The decision means that this will become a class issue as those affected will have to finance their own treatment in order to have a functioning sex life," she added. The Supreme Administrative Court said in its ruling that the lack of specialist physicians in many parts of the country made it difficult to make a diagnosis. As such, there was a clear risk that a disproportionate number of patients would be prescribed with the drugs. best buy meridia phentermine propecia viagra Generic Viagra is a drug used for erectile dysfunctions, or male impotence, and it represents the name for a substance known as sildenafil citrate. The substance is the same, while the market name of the drug may vary and so may its price. Generic versions for many types of drugs have been around for quite some time, but Generic Viagra is a fairly new drug on the market, and it gives men a chance at treating their erectile dysfunctions in an affordable way. Generic Viagra can be expected to have the same effects that the brand name Viagra does, because both drugs have the same active ingredient. Therefore, if your doctor has decided that Viagra is safe for you, it means that you can also use Generic Viagra. How does Generic Viagra work? It increases your ability to have and sustain an erection by inhibiting the enzymes that degrade the cyclic guanosine monophosphate, a substance that facilitates the influx of blood into the penis, by relaxing its spongy tissue. In other words, Viagra dilates blood vessels in the penis, and allows the necessary inflow of blood that an erection requires. Viagra can cause erections only when a man is sexually excited. This is the reason why this drug is not for regular use. It should be taken about one hour before sexual activity, and once the sexual intercourse is over the erection goes away. The efficacy of Generic Viagra has been evaluated based on self-assessment questionnaires, and this evaluation has shown that this drug is responsible for the sexual function improvement of almost ninety percent of those who have used it to treat their erectile dysfunctions. The evaluation included firmness, frequency, and ability to maintain an erection; level and frequency of desire; frequency of orgasm; sexual intercourse satisfaction; and relationship satisfaction. When it comes to the side effects that Generic Viagra can have, it is difficult to anticipate them. Your doctor should be informed shortly after the development of a side effect has occurred, or it has changed its intensity. Some of the side effects of Generic Viagra that are more likely to be experienced by those who use it as treatment include headache, abnormal vision, diarrhea, indigestion, urinary tract infection, and nasal congestion. There are other possible side effects, but these have been experienced at a considerably lower frequency. Remember that it is hard to predict how your body will react to this drug. Chances are that you’ll be just fine, if you don’t have a preexisting condition, such as a heart problem. However, you should inform your doctor about any modification that may occur, and he/she will tell you whether or not you should keep taking Generic Viagra. It is the doctor once again that will give you the most detailed information about the food and drugs Generic Viagra interacts with. It is a well-known fact that erectile dysfunction drugs should not be used simultaneously unless prescribed by a doctor. However, Generic Viagra may interact with other drugs as well, which is why you have to consult with your doctor before taking this medicine. He or she will also inform you about the special warnings that come with this medication, and what conditions do not allow the use of Generic Viagra. A sexual disorder is defined as the inability to enjoy sexual intercourse or having problems in the sex life. A person has difficulty in having or enjoying sex because of these disorders. It does not make any difference in the physical health but it can affect mental state by bringing on panic attacks, anxiety and feelings of depression. Sexual disorders occur in both men and women. It is not easy to diagnose a person with a sexual disorder because not everyone interested in sexual intercourse all the time. Some may not be interested in having sex at all and some have a lower level of desire or sexual need. If there are no symptoms of depression, no relationship problem, but still no interest in sex then, it can be classified as a sexual disorder. Consulting your doctor is the first best step in identifying a sexual disorder. These disorders are quite common and create lot of stress because people feel uncomfortable talking about sexual disorders, even to their doctors. Sexual activity needs comfortable environment, concentration and relaxation. Depending on the cause of sexual disorder, there are various treatments. If it is a physical problem, medication and different therapies can be done. If it is a psychological cause, it is best to consult with sexologists. Sexologists use different therapies to produce interest in sex. Psychotherapies can also be beneficial in this regard. Relationship therapists deal with relationship problems and stress, which may be the cause of the sexual disorder. Vasodilators, Minoxidil, Yohimbine Therapy

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Message copied & clipped from an e-mail we recieved from a more than happy customer. Wow what can I say… an amazing experience. In August a couple of my friends and I had planned to go on a short break to Amsterdam to unwind from stress and worries of our normal lives. We already had lots of things planned to do while we were there but once we arrived we were suprised to see one of our mates had brought along ). I personally hadn’t tried this stuff before, but I was always anxious when joining a female in the ‘bedroom department’ just incase I under performed so the thought of buying viagra or a viagra alternative had always crossed my mind but I just simply didn’t get around to it. This made me quite excited to use it. On the second night of being there, our mate suggested for us to go to a strip bar and as you can imagine we hit bar after bar and ended up in you know where. My mate pulled out the strip of kamagra jellys and we got down to business! My friend who brought the kamagra originally gave me your website address so I could buy some more at a later date. So I decided to e-mail you guys with a short story of my experience of generic viagra. Oh and yes, the sex was amazing!

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Life is, of course, all about managing death. Or rather, it's all about managing pain and pollution and disease and gravity and germs and bacteria and poison and Dick Cheney and those little shards of glass in your burrito; it's all about, in short, how you sort through the sundry and ever-increasing laundry list of things in your immediate world that want to torment and toxify and destroy you because oh my God they are legion and they are ready and they are . . Did you know? It shouldn't come as much of a surprise, really, given how many millions of drug-blasted Americans inhale prescription meds by the fistful and then hit the bathroom and the water flows and the treatment plant churns and pumps it all back into municipal water pipes, still brimming with trace amounts of Xanax and Zoloft and Medrol and Norvasc, asthma drugs and cholesterol drugs and birth control pills, cancer drugs and painkillers and diuretics and who the hell knows what else. Hell, who needs Vitamin Water when there's Lipitor in your ice cubes? This is the wacky fun reminder: Living in the city is deadly and toxic a million ways from Sunday. in every breath, electromagnetic waves in every gizmo, plastic off-gassing and high-VOC paints and chemicals in the carpet and toxins in your very clothing and every modern home so packed with thriving bacteria and synthetic substances and venomous Glade air fresheners it's a wonder we manage to stay upright at all. Hell, they just discovered that even our national parks, the fish and trees and lakes and the snow itself, are hugely polluted, . Go ahead, hug that tree. But be sure to wear a body condom. This is what we have to accept: You do not avoid poison. You do not escape toxin or chemical or gravity or modern synthetic residue even if you move to the woods and build a humble off-grid shack made only of fresh pine needles and bird dung and make your own jam out of river moss and beetle larvae because, hey look, up there in the sky, it's the very air itself, full of chemicals and pollutants drifting over from China and India and, um, Marin County, and you're breathing it in and it's coating the very trees and raining down upon your organic tomatoes right now. Sorry. Please enjoy your salad. No, you do not escape. You cannot completely block. You merely minimize. You recognize the most dire sources and most abhorrent problems and you choose your battles wisely, as you acknowledge just how complicit you are in all of it, how much you contribute to the problem, and adjust and recalibrate your life accordingly. This is the first, mandatory, all-important step. But more important than that, you learn to shun the paranoia. You gotta mock the relentless direness and shrug off the gods of death, every single day, even as they seem to be multiplying like rabid evangelicals at a Colorado megachurch. You gotta keep perspective, recall how man has been under deadly pressure from himself since the dawn of time. Otherwise, well, life is merely an army of demons and sins lined up and ready to take a bite out of your sweet, innocent flesh as you stroll by like a virgin at a porn convention. You know? Wait, did I mention sin? Good thing. Because apparently they've . Did you hear? Indeed, a dour red-robed figure just slithered out of the shadows of the Vatican and proclaimed some new additions to the master list of Thou Shalt Nots, adding juicy tidbits like pedophilia and pollution and the taking/dealing of drugs (then you'd best not drink the water, father) and questions of bioethics (stem cell research, cloning, whatnot) to the massive catalog of things that make God scowl and angels whine and for which we are all surely going to Hell like, a billion times over. Is this not delightful, in a deeply pathetic and insulting sort of way? Is it not amusing that, after 2,000 years, they're finally saying, hey gosh, trashing the planet and abusing creation itself is sort of wrong? Or that they — the Catholic Church! — dared to add pedophilia to the list, which is a bit like McDonald's announcing that beef is bad for you? Yo, preacher: Heal thyself, OK? As for bioethics, well, of course they worry that we'll try to "play God," which is just sort of cute and ridiculous given how most of us, you know, , every single day, by defying death and tormenting our bodies and launching brutal unwinnable wars (in the name of God, natch), choosing whether or not to eat meat and destroy plants and get pregnant or fall in love or hate gay people or buy an Escalade or enjoy Adam Sandler movies. Playing God? Who the hell is playing? God, that's where the real action is. And now, the bad news: They didn't remove a single damnable thing. They did not say, OK, we've added some vile and obvious new sins, so just for the sake of balance and just so you don't think we're authoritarian cretins, let's remove a few of the outdated, insulting ones, shall we? Condoms? Birth control? Go for it (they should've said). Pre-marital sex? Have at it, children. In fact, it's now highly recommended. Especially if you do it right. And often. And develop some mad skills so if you ever get married you can keep surprising each other with delightful new ways to enjoy various kitchen tools and yoga straps and Viagra chewing gum. Praise Jesus. Better yet, they should take it a step further, and for every new sin they add, they should remove . This way, eventually we'll whittle it down to just one grand sin, one terrifically all-encompassing God-mocking insult. Which is, of course, the idea of sin itself. Believe in sin? Believe that we're all, at our core, corrupt and evil and mortally flawed and that life is basically a grueling slog against disease and pain and pollution and 10,000 household poisons until you eventually whimper and sigh and lay yourself in a chemical-soaked pine box and sink it six feet under? Baby, that's the biggest sin of all. And you are hereby absolved. Thoughts about this column? . You have to be cautious. There are literally thousands of internet operations ready to sell you unregulated versions of Pfizer's Viagra. Often the sites claim to be selling the real thing, and it can be a daunting task to identify a safe resource for genuine, Pfizer Viagra. Ukmedix has had to compete with these fakes (which often are cheaper) and has even had to assist in identifying illegal operations (fakes are a threat to your safety, and ultimately Pfizer). In order to stand out from the crowd and reassure our customers Ukmedix produces useful customer tools e.g. a forum dedicated to viagra and makes sure that with every order sent batch numbers and manufacturer;s hall marks are always maintained. Dispatch pharmacists* are always available on receipt of your order for any further queries of authenticity. This means you can trace the product all the way back to Pfizer's manufacturing facility and even know the date your viagra was produced. *A UK pharmacist will always be able to assist you and any licensed pharmacy should be able to verify the viagra batch number. Apart from being unsafe and more then likely to be completely ineffective, fake viagra (wherever it has been produced) has passed no tests, is unregulated and for all you know may have been produced in a garden shed. In some instances dangerous substances have been found in this copied viagra, which would completely defeat the purpose of your seeking help with impotence in the first place! Ukmedix is obviously a business, but we care about our reputation and we care about our customers. We support Pfizer's Safe Drug Initiative which has been created to specifically find and close any illegal sellers of the unsubstantiated, fake viagra being sold on and offline. To this extent we want to know if you have been sold viagra that you think may be fake or viagra that doesn't look like it should. Contact ukmedix and we will gladly assist you and qualify your findings to Pfizer on your behalf. The fact is that fake viagra could have any substances in it and it is not to be trusted as a suitable replacement for the real thing. Impotence is a health condition that may be complex in its causes. Unnecessary e-mail spam on viagra or ludicrous claims that viagra will fix everything in your life are not what we are about. We never send out unsolicited e-mail and try to encourage you to research as much as you can yourself/ through your doctor and local pharmacists. Viagra has truly revolutionized many millions of lives, but viagra (that is Pfizer's viagra) is not suitable for everybody, and fake viagra is suitable for NO-ONE

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HE is only two, but Oliver Sherwood regularly takes Viagra - to keep him alive. The toddler has a rare condition that causes chronic high blood pressure. Something as simple a chest infection could kill him. The pulmonary hypertension, as it is known, can be controlled with four doses of Viagra a day. The drug improves blood flow, which in adults can boost erectile function but in rare cases such as Oliver's can open the veins and capillaries to aid circulation. His mother Sarah, a part-time nurse, said: "We joke when we pick up his drugs that it would be Christmas come early for most people. Obviously the dose isn't high enough to have the effect it would on adults. "Viagra is an expensive drug but it's actually one of the cheapest to treat pulmonary hypertension. "We're just hoping it'll continue to work as he grows a bit older." But Oliver's future could be in doubt because other drugs he could use as he gets older might no longer be funded by the Health Service. Pulmonary hypertension causes the blood pressure in the arteries in the lungs to rise, straining the heart and reducing blood oxygen levels, causing breathlessness and exhaustion. Symptoms include severe coughing and breathing problems as blood fills the lungs, constant nose bleeds, dizziness and chest pains. The condition, which affects 4,000 in Britain, often leads to heart failure. It is so rare that only five children a year are diagnosed with it in the UK. The survival rate is around five years, even with medication such as Oliver, who cannot walk more than a few steps without getting out of breath, takes one tablet of Sildenafil crushed into four 5ml doses a day. Doctors can increase the dose when his condition worsens, but there is no way of telling how much longer the drugs will be effective. As he grows up he will need to switch to more expensive treatments called Epoprostenol and Iloprost to control his condition. But the Government's drug rationing agency, the National Institute for Health and Clinical Excellence, is considering whether to continue prescribing them. Oliver's mother has started a petition calling for the Health Service to keep funding the treatments. Mrs Sherwood, 34, of Hucclecote, Gloucestershire, said: "The only hope we had was that he would be maintained through medication but if anything-happens in the future that hope may be taken away." The Pulmonary Hypertension Association said: "The clinical evidence for this is unfounded and it must be assumed it is based on cost alone." A spokesman for NICE added: "Our review of the evidence suggests that Sildenafil is both clinically effective and cost-effective in treating pulmonary arterial hypertension."

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The latest alert was prompted by a case report in the Journal of Laryngology & Otology of sudden hearing loss in a man taking Viagra. A search of FDA records found 29 similar reports involving ED drug users and a few people who took the drugs during clinical trials. Although hearing loss is common in men in their 50s -- the age group most likely to take ED drugs -- age-related loss tends to be gradual, unlike the kind tied to the warning. The FDA has also issued a hearing-loss warning on Revatio, a blood pressure drug in the same class. Revatio users who experience hearing problems should stay on the drug until they have checked with their doctor. ED drugs, on the market for more than a decade, generally have an excellent safety record. More-common problems include flushing and muscle soreness.  natural source of sildenafil citrate Jetlag is defined as a temporary disturbance of the bodily rhythms which is caused by high-speed travel, whether it is on land or on air and across various time zone. This disturbance is usually common in jet aircrafts. People who cross various time zones find it easier to recover from jet lag if the purpose of the travel is for a vacation. This is because when a person travels to a place where he is allowed to relax and recover slowly, it gives him the chance to adjust to the local time of the area. But there are also persons who are not that lucky. People who travel for business purposes usually cross a lot of time zones. When the business traveler reaches his destination he gets busy attending meetings and doing the work that has to be done all based on the local time of that certain place. Thus the business travelers cannot afford the luxury of relaxing and adjusting their bodies to the place's local time. Can Viagra be a relief for jetlag? It is usually not known that there is a certain link between Jetlag and Viagra. A recent study has shown that not only does Viagra treat erectile dysfunction but it can actually also neutralize the effects of jetlag. Viagra has been observed to restore normal bodily clock functions which have been shifted by six hours. Viagra was first developed by Pfizer for aid in treatment of angina and high blood pressure by disturbing the enzyme that causes the reduction of cGMP, a natural compound, cGMP plays a very important in the function of penile erection. In relation to jetlag, cGMP acts in a region of the brain whose role is to regulate the circadian cycle. The circadian cycle is the body's internal clock that determines the waning and the waxing of hormones and also controls the urge to sleep and wake. In a laboratory test, hamsters were injected with Viagra and subjected to bright lights for 6 hours ahead of the regular time. They were observed by a team of researchers from the Universidad Nacional de Quilmes. They found that the injected hamsters have improved in coping with the time difference by 25 to 50 percent as those compared to the hamsters that were not administered with Viagra. The testing gave out a positive result in the light to dark cycle which is the equivalent of traveling from west to east. Further test is needed to really identify the possibility of Viagra as an effective treatment to counter the ill feeling of traveler's jetlag. If this can be validated, then the blue pill can cross the barrier of time and human dysfunction.

pharmacokinetics of sildenafil citrate

An oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). Sildenafil citrate is designated chemically as 1 - [[3 - (6,7 - dihydro - 1 - methyl - 7 - oxo - 3 - propyl - 1H - pyrazolo[4,3 - d]pyrimidin - 5 - yl) - 4 - ethoxyphenyl]sulfonyl] - 4 - methylpiperazine citrate and has the following structural formula: Sildenafil citrate is a white to off-white crystalline powder with a solubility of 3.5 mg/mL in water and a molecular weight of 666.7. Viagra (sildenafil citrate) is formulated as blue, film-coated rounded-diamond-shaped tablets equivalent to 25 mg, 50 mg and 100 mg of sildenafil for oral administration. In addition to the active ingredient, sildenafil citrate, each tablet contains the following inactive ingredients: microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hypromellose, titanium dioxide, lactose, triacetin, and FD & C Blue #2 aluminum lake. The physiologic mechanism of erection of the penis involves release of nitric oxide (NO) in the corpus cavernosum during sexual stimulation. NO then activates the enzyme guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP), producing smooth muscle relaxation in the corpus cavernosum and allowing inflow of blood. Sildenafil has no direct relaxant effect on isolated human corpus cavernosum, but enhances the effect of nitric oxide (NO) by inhibiting phosphodiesterase type 5 (PDE5), which is responsible for degradation of cGMP in the corpus cavernosum. When sexual stimulation causes local release of NO, inhibition of PDE5 by sildenafil causes increased levels of cGMP in the corpus cavernosum, resulting in smooth muscle relaxation and inflow of blood to the corpus cavernosum. Sildenafil at recommended doses has no effect in the absence of sexual stimulation. Studies in vitro have shown that sildenafil is selective for PDE5. Its effect is more potent on PDE5 than on other known phosphodiesterases (10-fold for PDE6, >80-fold for PDE1, >700-fold for PDE2, PDE3, PDE4, PDE7, PDE8, PDE9, PDE10, and PDE11). The approximately 4,000-fold selectivity for PDE5 versus PDE3 is important because PDE3 is involved in control of cardiac contractility. Sildenafil is only about 10-fold as potent for PDE5 compared to PDE6, an enzyme found in the retina which is involved in the phototransduction pathway of the retina. This lower selectivity is thought to be the basis for abnormalities related to color vision observed with higher doses or plasma levels (see ). In addition to human corpus cavernosum smooth muscle, PDE5 is also found in lower concentrations in other tissues including platelets, vascular and visceral smooth muscle, and skeletal muscle. The inhibition of PDE5 in these tissues by sildenafil may be the basis for the enhanced platelet antiaggregatory activity of nitric oxide observed in vitro, an inhibition of platelet thrombus formation in vivo and peripheral arterial-venous dilatation in vivo. Viagra is rapidly absorbed after oral administration, with absolute bioavailability of about 40%. Its pharmacokinetics are dose-proportional over the recommended dose range. It is eliminated predominantly by hepatic metabolism (mainly cytochrome P450 3A4) and is converted to an active metabolite with properties similar to the parent, sildenafil. The concomitant use of potent cytochrome P450 3A4 inhibitors (e.g., erythromycin, ketoconazole, itraconazole) as well as the nonspecific CYP inhibitor, cimetidine, is associated with increased plasma levels of sildenafil (see ). Both sildenafil and the metabolite have terminal half lives of about 4 hours. in Healthy Male Volunteers. Viagra is rapidly absorbed. Maximum observed plasma concentrations are reached within 30 to 120 minutes (median 60 minutes) of oral dosing in the fasted state. When Viagra is taken with a high fat meal, the rate of absorption is reduced, with a mean delay in T of 29%. The mean steady state volume of distribution (Vss) for sildenafil is 105 L, indicating distribution into the tissues. Sildenafil and its major circulating N-desmethyl metabolite are both approximately 96% bound to plasma proteins. Protein binding is independent of total drug concentrations. Based upon measurements of sildenafil in semen of healthy volunteers 90 minutes after dosing, less than 0.001% of the administered dose may appear in the semen of patients. Sildenafil is cleared predominantly by the CYP3A4 (major route) and CYP2C9 (minor route) hepatic microsomal isoenzymes. The major circulating metabolite results from N-desmethylation of sildenafil, and is itself further metabolized. This metabolite has a PDE selectivity profile similar to sildenafil and an in vitro potency for PDE5 approximately 50% of the parent drug. Plasma concentrations of this metabolite are approximately 40% of those seen for sildenafil, so that the metabolite accounts for about 20% of sildenafil's pharmacologic effects. After either oral or intravenous administration, sildenafil is excreted as metabolites predominantly in the feces (approximately 80% of administered oral dose) and to a lesser extent in the urine (approximately 13% of the administered oral dose). Similar values for pharmacokinetic parameters were seen in normal volunteers and in the patient population, using a population pharmacokinetic approach. Healthy elderly volunteers (65 years or over) had a reduced clearance of sildenafil, with free plasma concentrations approximately 40% greater than those seen in healthy younger volunteers (18–45 years). In volunteers with mild (CLcr=50–80 mL/min) and moderate (CLcr=30–49 mL/min) renal impairment, the pharmacokinetics of a single oral dose of Viagra (50 mg) were not altered. In volunteers with severe (CLcr=<30 mL/min) renal impairment, sildenafil clearance was reduced, resulting in approximately doubling of AUC and C compared to age-matched volunteers with no renal impairment. In volunteers with hepatic cirrhosis (Child-Pugh A and B), sildenafil clearance was reduced, resulting in increases in AUC (84%) and C (47%) compared to age-matched volunteers with no hepatic impairment. Therefore, age >65, hepatic impairment and severe renal impairment are associated with increased plasma levels of sildenafil. A starting oral dose of 25 mg should be considered in those patients (see ). In eight double-blind, placebo-controlled crossover studies of patients with either organic or psychogenic erectile dysfunction, sexual stimulation resulted in improved erections, as assessed by an objective measurement of hardness and duration of erections (RigiScan ), after Viagra administration compared with placebo. Most studies assessed the efficacy of Viagra approximately 60 minutes post dose. The erectile response, as assessed by RigiScan , generally increased with increasing sildenafil dose and plasma concentration. The time course of effect was examined in one study, showing an effect for up to 4 hours but the response was diminished compared to 2 hours. Single oral doses of sildenafil (100 mg) administered to healthy volunteers produced decreases in supine blood pressure (mean maximum decrease in systolic/diastolic blood pressure of 8.4/5.5 mmHg). The decrease in blood pressure was most notable approximately 1–2 hours after dosing, and was not different than placebo at 8 hours. Similar effects on blood pressure were noted with 25 mg, 50 mg and 100 mg of Viagra, therefore the effects are not related to dose or plasma levels within this dosage range. Larger effects were recorded among patients receiving concomitant nitrates (see ). Systolic Blood Pressure, Healthy Volunteers. Single oral doses of sildenafil up to 100 mg produced no clinically relevant changes in the ECGs of normal male volunteers. Studies have produced relevant data on the effects of Viagra on cardiac output. In one small, open-label, uncontrolled, pilot study, eight patients with stable ischemic heart disease underwent Swan-Ganz catheterization. A total dose of 40 mg sildenafil was administered by four intravenous infusions. The results from this pilot study are shown in Table 1; the mean resting systolic and diastolic blood pressures decreased by 7% and 10% compared to baseline in these patients. Mean resting values for right atrial pressure, pulmonary artery pressure, pulmonary artery occluded pressure and cardiac output decreased by 28%, 28%, 20% and 7% respectively. Even though this total dosage produced plasma sildenafil concentrations which were approximately 2 to 5 times higher than the mean maximum plasma concentrations following a single oral dose of 100 mg in healthy male volunteers, the hemodynamic response to exercise was preserved in these patients. In a double-blind study, 144 patients with erectile dysfunction and chronic stable angina limited by exercise, not receiving chronic oral nitrates, were randomized to a single dose of placebo or Viagra 100 mg 1 hour prior to exercise testing. The primary endpoint was time to limiting angina in the evaluable cohort. The mean times (adjusted for baseline) to onset of limiting angina were 423.6 and 403.7 seconds for sildenafil (N=70) and placebo, respectively. These results demonstrated that the effect of Viagra on the primary endpoint was statistically non-inferior to placebo. At single oral doses of 100 mg and 200 mg, transient dose-related impairment of color discrimination (blue/green) was detected using the Farnsworth-Munsell 100-hue test, with peak effects near the time of peak plasma levels. This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. An evaluation of visual function at doses up to twice the maximum recommended dose revealed no effects of Viagra on visual acuity, intraocular pressure, or pupillometry. In clinical studies, Viagra was assessed for its effect on the ability of men with erectile dysfunction (ED) to engage in sexual activity and in many cases specifically on the ability to achieve and maintain an erection sufficient for satisfactory sexual activity. Viagra was evaluated primarily at doses of 25 mg, 50 mg and 100 mg in 21 randomized, double-blind, placebo-controlled trials of up to 6 months in duration, using a variety of study designs (fixed dose, titration, parallel, crossover). Viagra was administered to more than 3,000 patients aged 19 to 87 years, with ED of various etiologies (organic, psychogenic, mixed) with a mean duration of 5 years. Viagra demonstrated statistically significant improvement compared to placebo in all 21 studies. The studies that established benefit demonstrated improvements in success rates for sexual intercourse compared with placebo. The effectiveness of Viagra was evaluated in most studies using several assessment instruments. The primary measure in the principal studies was a sexual function questionnaire (the International Index of Erectile Function - IIEF) administered during a 4-week treatment-free run-in period, at baseline, at follow-up visits, and at the end of double-blind, placebo-controlled, at-home treatment. Two of the questions from the IIEF served as primary study endpoints; categorical responses were elicited to questions about (1) the ability to achieve erections sufficient for sexual intercourse and (2) the maintenance of erections after penetration. The patient addressed both questions at the final visit for the last 4 weeks of the study. The possible categorical responses to these questions were (0) no attempted intercourse, (1) never or almost never, (2) a few times, (3) sometimes, (4) most times, and (5) almost always or always. Also collected as part of the IIEF was information about other aspects of sexual function, including information on erectile function, orgasm, desire, satisfaction with intercourse, and overall sexual satisfaction. Sexual function data were also recorded by patients in a daily diary. In addition, patients were asked a global efficacy question and an optional partner questionnaire was administered. The effect on one of the major end points, maintenance of erections after penetration, is shown in Figure 3, for the pooled results of 5 fixed-dose, dose-response studies of greater than one month duration, showing response according to baseline function. Results with all doses have been pooled, but scores showed greater improvement at the 50 and 100 mg doses than at 25 mg. The pattern of responses was similar for the other principal question, the ability to achieve an erection sufficient for intercourse. The titration studies, in which most patients received 100 mg, showed similar results. Figure 3 shows that regardless of the baseline levels of function, subsequent function in patients treated with Viagra was better than that seen in patients treated with placebo. At the same time, on-treatment function was better in treated patients who were less impaired at baseline. Figure 3. Effect of Viagra and Placebo on Maintenance of Erection by Baseline Score. The frequency of patients reporting improvement of erections in response to a global question in four of the randomized, double-blind, parallel, placebo-controlled fixed dose studies (1797 patients) of 12 to 24 weeks duration is shown in Figure 4. These patients had erectile dysfunction at baseline that was characterized by median categorical scores of 2 (a few times) on principal IIEF questions. Erectile dysfunction was attributed to organic (58%; generally not characterized, but including diabetes and excluding spinal cord injury), psychogenic (17%), or mixed (24%) etiologies. Sixty-three percent, 74%, and 82% of the patients on 25 mg, 50 mg and 100 mg of Viagra, respectively, reported an improvement in their erections, compared to 24% on placebo. In the titration studies (n=644) (with most patients eventually receiving 100 mg), results were similar. Figure 4. Percentage of Patients Reporting an Improvement in Erections. The patients in studies had varying degrees of ED. One-third to one-half of the subjects in these studies reported successful intercourse at least once during a 4-week, treatment-free run-in period. In many of the studies, of both fixed dose and titration designs, daily diaries were kept by patients. In these studies, involving about 1600 patients, analyses of patient diaries showed no effect of Viagra on rates of attempted intercourse (about 2 per week), but there was clear treatment-related improvement in sexual function: per patient weekly success rates averaged 1.3 on 50–100 mg of Viagra vs 0.4 on placebo; similarly, group mean success rates (total successes divided by total attempts) were about 66% on Viagra vs about 20% on placebo. During 3 to 6 months of double-blind treatment or longer-term (1 year), open-label studies, few patients withdrew from active treatment for any reason, including lack of effectiveness. At the end of the long-term study, 88% of patients reported that Viagra improved their erections. Men with untreated ED had relatively low baseline scores for all aspects of sexual function measured (again using a 5-point scale) in the IIEF. Viagra improved these aspects of sexual function: frequency, firmness and maintenance of erections; frequency of orgasm; frequency and level of desire; frequency, satisfaction and enjoyment of intercourse; and overall relationship satisfaction. One randomized, double-blind, flexible-dose, placebo-controlled study included only patients with erectile dysfunction attributed to complications of diabetes mellitus (n=268). As in the other titration studies, patients were started on 50 mg and allowed to adjust the dose up to 100 mg or down to 25 mg of Viagra; all patients, however, were receiving 50 mg or 100 mg at the end of the study. There were highly statistically significant improvements on the two principal IIEF questions (frequency of successful penetration during sexual activity and maintenance of erections after penetration) on Viagra compared to placebo. On a global improvement question, 57% of Viagra patients reported improved erections versus 10% on placebo. Diary data indicated that on Viagra, 48% of intercourse attempts were successful versus 12% on placebo. One randomized, double-blind, placebo-controlled, crossover, flexible-dose (up to 100 mg) study of patients with erectile dysfunction resulting from spinal cord injury (n=178) was conducted. The changes from baseline in scoring on the two end point questions (frequency of successful penetration during sexual activity and maintenance of erections after penetration) were highly statistically significantly in favor of Viagra. On a global improvement question, 83% of patients reported improved erections on Viagra versus 12% on placebo. Diary data indicated that on Viagra, 59% of attempts at sexual intercourse were successful compared to 13% on placebo. Across all trials, Viagra improved the erections of 43% of radical prostatectomy patients compared to 15% on placebo. Subgroup analyses of responses to a global improvement question in patients with psychogenic etiology in two fixed-dose studies (total n=179) and two titration studies (total n=149) showed 84% of Viagra patients reported improvement in erections compared with 26% of placebo. The changes from baseline in scoring on the two end point questions (frequency of successful penetration during sexual activity and maintenance of erections after penetration) were highly statistically significantly in favor of Viagra. Diary data in two of the studies (n=178) showed rates of successful intercourse per attempt of 70% for Viagra and 29% for placebo. A review of population subgroups demonstrated efficacy regardless of baseline severity, etiology, race and age. Viagra was effective in a broad range of ED patients, including those with a history of coronary artery disease, hypertension, other cardiac disease, peripheral vascular disease, diabetes mellitus, depression, coronary artery bypass graft (CABG), radical prostatectomy, transurethral resection of the prostate (TURP) and spinal cord injury, and in patients taking antidepressants/antipsychotics and antihypertensives/diuretics. Analysis of the safety database showed no apparent difference in the side effect profile in patients taking Viagra with and without antihypertensive medication. This analysis was performed retrospectively, and was not powered to detect any pre-specified difference in adverse reactions. Viagra is indicated for the treatment of erectile dysfunction. ), Viagra was shown to potentiate the hypotensive effects of nitrates, and its administration to patients who are using organic nitrates, either regularly and/or intermittently, in any form is therefore contraindicated. After patients have taken Viagra, it is unknown when nitrates, if necessary, can be safely administered. Based on the pharmacokinetic profile of a single 100 mg oral dose given to healthy normal volunteers, the plasma levels of sildenafil at 24 hours post dose are approximately 2 ng/mL (compared to peak plasma levels of approximately 440 ng/mL) (see ). In the following patients: age >65, hepatic impairment (e.g., cirrhosis), severe renal impairment (e.g., creatinine clearance <30 mL/min), and concomitant use of potent cytochrome P450 3A4 inhibitors (erythromycin), plasma levels of sildenafil at 24 hours post dose have been found to be 3 to 8 times higher than those seen in healthy volunteers. Although plasma levels of sildenafil at 24 hours post dose are much lower than at peak concentration, it is unknown whether nitrates can be safely coadministered at this time point. Viagra is contraindicated in patients with a known hypersensitivity to any component of the tablet. There is a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. Therefore, treatments for erectile dysfunction, including Viagra, should not be generally used in men for whom sexual activity is inadvisable because of their underlying cardiovascular status. Viagra has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 8.4/5.5 mmHg), (see ). While this normally would be expected to be of little consequence in most patients, prior to prescribing Viagra, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Patients with the following underlying conditions can be particularly sensitive to the actions of vasodilators including Viagra – those with left ventricular outflow obstruction (e.g. aortic stenosis, idiopathic hypertrophic subaortic stenosis) and those with severely impaired autonomic control of blood pressure. There is no controlled clinical data on the safety or efficacy of Viagra in the following groups; if prescribed, this should be done with caution. Patients who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; Patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases). Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of Viagra. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result. The concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If Viagra is prescribed to patients taking ritonavir, caution should be used. Data from subjects exposed to high systemic levels of sildenafil are limited. Visual disturbances occurred more commonly at higher levels of sildenafil exposure. Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200–800 mg). To decrease the chance of adverse events in patients taking ritonavir, a decrease in sildenafil dosage is recommended (see , ). The evaluation of erectile dysfunction should include a determination of potential underlying causes and the identification of appropriate treatment following a complete medical assessment. Before prescribing Viagra, it is important to note the following: Caution is advised when Phosphodiesterase Type 5 (PDE5) inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including Viagra, and alpha-adrenergic blocking agents are both vasodilators with blood pressure lowering effects. When vasodilators are used in combination, an additive effect on blood pressure may be anticipated. In some patients, concomitant use of these two drug classes can lower blood pressure significantly (see ) leading to symptomatic hypotension (e.g. dizziness, lightheadedness, fainting). Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor. Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors. In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose. In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose. Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor. Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs. Viagra has systemic vasodilatory properties and may augment the blood pressure lowering effect of other anti-hypertensive medications. Patients on multiple antihypertensive medications were included in the pivotal clinical trials for Viagra. In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and Viagra, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted (see ). The safety of Viagra is unknown in patients with bleeding disorders and patients with active peptic ulceration. Viagra should be used with caution in patients with anatomical deformation of the penis (such as angulation, cavernosal fibrosis or Peyronie's disease), or in patients who have conditions which may predispose them to priapism (such as sickle cell anemia, multiple myeloma, or leukemia). The safety and efficacy of combinations of Viagra with other treatments for erectile dysfunction have not been studied. Therefore, the use of such combinations is not recommended. In humans, Viagra has no effect on bleeding time when taken alone or with aspirin. In vitro studies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor). The combination of heparin and Viagra had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans. Physicians should discuss with patients the contraindication of Viagra with regular and/or intermittent use of organic nitrates. Physicians should advise patients of the potential for Viagra to augment the blood pressure lowering effect of alpha-blockers and anti-hypertensive medications. Concomitant administration of Viagra and an alpha-blocker may lead to symptomatic hypotension in some patients. Therefore, when Viagra is co-administered with alpha-blockers, patients should be stable on alpha-blocker therapy prior to initiating Viagra treatment and Viagra should be initiated at the lowest dose. Physicians should discuss with patients the potential cardiac risk of sexual activity in patients with preexisting cardiovascular risk factors. Patients who experience symptoms (e.g., angina pectoris, dizziness, nausea) upon initiation of sexual activity should be advised to refrain from further activity and should discuss the episode with their physician. Physicians should advise patients to stop use of all PDE5 inhibitors, including Viagra, and seek medical attention in the event of a sudden loss of vision in one or both eyes. Such an event may be a sign of non-arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision, that has been reported rarely post-marketing in temporal association with the use of all PDE5 inhibitors. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors. Physicians should also discuss with patients the increased risk of NAION in individuals who have already experienced NAION in one eye, including whether such individuals could be adversely affected by use of vasodilators, such as PDE5 inhibitors (see ). Physicians should advise patients to stop taking PDE5 inhibitors, including Viagra, and seek prompt medical attention in the event of sudden decrease or loss of hearing. These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including Viagra. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors (see , ). Physicians should warn patients that prolonged erections greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of Viagra. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency may result. The use of Viagra offers no protection against sexually transmitted diseases. Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered. Sildenafil metabolism is principally mediated by the cytochrome P450 (CYP) isoforms 3A4 (major route) and 2C9 (minor route). Therefore, inhibitors of these isoenzymes may reduce sildenafil clearance. Cimetidine (800 mg), a nonspecific CYP inhibitor, caused a 56% increase in plasma sildenafil concentrations when coadministered with Viagra (50 mg) to healthy volunteers. When a single 100 mg dose of Viagra was administered with erythromycin, a specific CYP3A4 inhibitor, at steady state (500 mg bid for 5 days), there was a 182% increase in sildenafil systemic exposure (AUC). In addition, in a study performed in healthy male volunteers, coadministration of the HIV protease inhibitor saquinavir, also a CYP3A4 inhibitor, at steady state (1200 mg tid) with Viagra (100 mg single dose) resulted in a 140% increase in sildenafil C and a 210% increase in sildenafil AUC. Viagra had no effect on saquinavir pharmacokinetics. Stronger CYP3A4 inhibitors such as ketoconazole or itraconazole would be expected to have still greater effects, and population data from patients in clinical trials did indicate a reduction in sildenafil clearance when it was coadministered with CYP3A4 inhibitors (such as ketoconazole, erythromycin, or cimetidine) (see ). In another study in healthy male volunteers, coadministration with the HIV protease inhibitor ritonavir, which is a highly potent P450 inhibitor, at steady state (500 mg bid) with Viagra (100 mg single dose) resulted in a 300% (4-fold) increase in sildenafil C and a 1000% (11-fold) increase in sildenafil plasma AUC. At 24 hours the plasma levels of sildenafil were still approximately 200 ng/mL, compared to approximately 5 ng/mL when sildenafil was dosed alone. This is consistent with ritonavir's marked effects on a broad range of P450 substrates. Viagra had no effect on ritonavir pharmacokinetics (see ). Although the interaction between other protease inhibitors and sildenafil has not been studied, their concomitant use is expected to increase sildenafil levels. In a study of healthy male volunteers, co-administration of sildenafil at steady state (80 mg t.i.d.) with endothelin receptor antagonist bosentan (a moderate inducer of CYP3A4, CYP2C9 and possibly of cytochrome P450 2C19) at steady state (125 mg b.i.d.) resulted in a 63% decrease of sildenafil AUC and a 55% decrease in sildenafil C . Concomitant administration of strong CYP3A4 inducers, such as rifampin, is expected to cause greater decreases in plasma levels of sildenafil. Single doses of antacid (magnesium hydroxide/aluminum hydroxide) did not affect the bioavailability of Viagra. Pharmacokinetic data from patients in clinical trials showed no effect on sildenafil pharmacokinetics of CYP2C9 inhibitors (such as tolbutamide, warfarin), CYP2D6 inhibitors (such as selective serotonin reuptake inhibitors, tricyclic antidepressants), thiazide and related diuretics, ACE inhibitors, and calcium channel blockers. The AUC of the active metabolite, N-desmethyl sildenafil, was increased 62% by loop and potassium-sparing diuretics and 102% by nonspecific beta-blockers. These effects on the metabolite are not expected to be of clinical consequence. Sildenafil is a weak inhibitor of the cytochrome P450 isoforms 1A2, 2C9, 2C19, 2D6, 2E1 and 3A4 (IC50 >150 µM). Given sildenafil peak plasma concentrations of approximately 1 µM after recommended doses, it is unlikely that Viagra will alter the clearance of substrates of these isoenzymes. Three double-blind, placebo-controlled, randomized, two-way crossover studies were conducted to assess the interaction of Viagra with doxazosin, an alpha-adrenergic blocking agent. In the first study, a single oral dose of Viagra 100 mg or matching placebo was administered in a 2-period crossover design to 4 generally healthy males with benign prostatic hyperplasia (BPH). Following at least 14 consecutive daily doses of doxazosin, Viagra 100 mg or matching placebo was administered simultaneously with doxazosin. Following a review of the data from these first 4 subjects (details provided below), the Viagra dose was reduced to 25 mg. Thereafter, 17 subjects were treated with Viagra 25 mg or matching placebo in combination with doxazosin 4 mg (15 subjects) or doxazosin 8mg (2 subjects). The mean subject age was 66.5 years. For the 17 subjects who received Viagra 25 mg and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows: Blood pressure was measured immediately pre-dose and at 15, 30, 45 minutes, and 1, 1.5, 2, 2.5, 3, 4, 6 and 8 hours after Viagra or matching placebo. Outliers were defined as subjects with a standing systolic blood pressure of <85 mmHg or a decrease from baseline in standing systolic blood pressure of >30 mmHg at one or more timepoints. There were no subjects treated with Viagra 25 mg who had a standing SBP < 85mmHg. There were three subjects with a decrease from baseline in standing systolic BP >30mmHg following Viagra 25 mg, one subject with a decrease from baseline in standing systolic BP > 30 mmHg following placebo and two subjects with a decrease from baseline in standing systolic BP > 30 mmHg following both Viagra and placebo. No severe adverse events potentially related to blood pressure effects were reported in this group. Of the four subjects who received Viagra 100 mg in the first part of this study, a severe adverse event related to blood pressure effect was reported in one patient (postural hypotension that began 35 minutes after dosing with Viagra with symptoms lasting for 8 hours), and mild adverse events potentially related to blood pressure effects were reported in two others (dizziness, headache and fatigue at 1 hour after dosing; and dizziness, lightheadedness and nausea at 4 hours after dosing). There were no reports of syncope among these patients. For these four subjects, the placebo-subtracted mean maximum decreases from baseline in supine and standing systolic blood pressures were 14.8 mmHg and 21.5 mmHg, respectively. Two of these subjects had a standing SBP < 85mmHg. Both of these subjects were protocol violators, one due to a low baseline standing SBP, and the other due to baseline orthostatic hypotension. In the second study, a single oral dose of Viagra 50 mg or matching placebo was administered in a 2-period crossover design to 20 generally healthy males with BPH. Following at least 14 consecutive days of doxazosin, Viagra 50mg or matching placebo was administered simultaneously with doxazosin 4 mg (17 subjects) or with doxazosin 8 mg (3 subjects). The mean subject age in this study was 63.9 years. Twenty subjects received Viagra 50 mg, but only 19 subjects received matching placebo. One patient discontinued the study prematurely due to an adverse event of hypotension following dosing with Viagra 50 mg. This patient had been taking minoxidil, a potent vasodilator, during the study. For the 19 subjects who received both Viagra and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows: Blood pressure was measured after administration of Viagra at the same times as those specified for the first doxazosin study. There were two subjects who had a standing SBP of < 85 mmHg. In these two subjects, hypotension was reported as a moderately severe adverse event, beginning at approximately 1 hour after administration of Viagra 50 mg and resolving after approximately 7.5 hours. There was one subject with a decrease from baseline in standing systolic BP >30mmHg following Viagra 50 mg and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both Viagra 50 mg and placebo. There were no severe adverse events potentially related to blood pressure and no episodes of syncope reported in this study. In the third study, a single oral dose of Viagra 100 mg or matching placebo was administered in a 3-period crossover design to 20 generally healthy males with BPH. In dose period 1, subjects were administered open-label doxazosin and a single dose of Viagra 50 mg simultaneously, after at least 14 consecutive days of doxazosin. If a subject did not successfully complete this first dosing period, he was discontinued from the study. Subjects who had successfully completed the previous doxazosin interaction study (using Viagra 50 mg), including no significant hemodynamic adverse events, were allowed to skip dose period 1. Treatment with doxazosin continued for at least 7 days after dose period 1. Thereafter, Viagra 100mg or matching placebo was administered simultaneously with doxazosin 4 mg (14 subjects) or doxazosin 8 mg (6 subjects) in standard crossover fashion. The mean subject age in this study was 66.4 years. Twenty-five subjects were screened. Two were discontinued after study period 1: one failed to meet pre-dose screening qualifications and the other experienced symptomatic hypotension as a moderately severe adverse event 30 minutes after dosing with open-label Viagra 50 mg. Of the twenty subjects who were ultimately assigned to treatment, a total of 13 subjects successfully completed dose period 1, and seven had successfully completed the previous doxazosin study (using Viagra 50 mg). For the 20 subjects who received Viagra 100 mg and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows: Blood pressure was measured after administration of Viagra at the same times as those specified for the previous doxazosin studies. There were three subjects who had a standing SBP of < 85 mmHg. All three were taking Viagra 100 mg, and all three reported mild adverse events at the time of reductions in standing SBP, including vasodilation and lightheadedness. There were four subjects with a decrease from baseline in standing systolic BP >30mmHg following Viagra 100 mg, one subject with a decrease from baseline in standing systolic BP > 30 mmHg following placebo and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both Viagra and placebo. While there were no severe adverse events potentially related to blood pressure reported in this study, one subject reported moderate vasodilatation after both Viagra 50 mg and 100 mg. There were no episodes of syncope reported in this study. When Viagra 100 mg oral was coadministered with amlodipine, 5 mg or 10 mg oral, to hypertensive patients, the mean additional reduction on supine blood pressure was 8 mmHg systolic and 7 mmHg diastolic. No significant interactions were shown with tolbutamide (250 mg) or warfarin (40 mg), both of which are metabolized by CYP2C9. Viagra (50 mg) did not potentiate the increase in bleeding time caused by aspirin (150 mg). Viagra (50 mg) did not potentiate the hypotensive effect of alcohol in healthy volunteers with mean maximum blood alcohol levels of 0.08%. In a study of healthy male volunteers, sildenafil (100 mg) did not affect the steady state pharmacokinetics of the HIV protease inhibitors, saquinavir and ritonavir, both of which are CYP3A4 substrates. Sildenafil at steady state (80 mg t.i.d.) resulted in a 50% increase in AUC and a 42% increase in C of bosentan (125 mg b.i.d.). Carcinogenesis, Mutagenesis, Impairment of Fertility Sildenafil was not carcinogenic when administered to rats for 24 months at a dose resulting in total systemic drug exposure (AUCs) for unbound sildenafil and its major metabolite of 29- and 42-times, for male and female rats, respectively, the exposures observed in human males given the Maximum Recommended Human Dose (MRHD) of 100 mg. Sildenafil was not carcinogenic when administered to mice for 18–21 months at dosages up to the Maximum Tolerated Dose (MTD) of 10 mg/kg/day, approximately 0.6 times the MRHD on a mg/m basis. Sildenafil was negative in in vitro bacterial and Chinese hamster ovary cell assays to detect mutagenicity, and in vitro human lymphocytes and in vivo mouse micronucleus assays to detect clastogenicity. There was no impairment of fertility in rats given sildenafil up to 60 mg/kg/day for 36 days to females and 102 days to males, a dose producing an AUC value of more than 25 times the human male AUC. There was no effect on sperm motility or morphology after single 100 mg oral doses of Viagra in healthy volunteers. Pregnancy, Nursing Mothers and Pediatric Use Viagra is not indicated for use in newborns, children, or women. No evidence of teratogenicity, embryotoxicity or fetotoxicity was observed in rats and rabbits which received up to 200 mg/kg/day during organogenesis. These doses represent, respectively, about 20 and 40 times the MRHD on a mg/m basis in a 50 kg subject. In the rat pre- and postnatal development study, the no observed adverse effect dose was 30 mg/kg/day given for 36 days. In the nonpregnant rat the AUC at this dose was about 20 times human AUC. There are no adequate and well-controlled studies of sildenafil in pregnant women. ). Since higher plasma levels may increase both the efficacy and incidence of adverse events, a starting dose of 25 mg should be considered (see ). Viagra was administered to over 3700 patients (aged 19–87 years) during pre-marketing clinical trials worldwide. Over 550 patients were treated for longer than one year. In placebo-controlled clinical studies, the discontinuation rate due to adverse events for Viagra (2.5%) was not significantly different from placebo (2.3%). The adverse events were generally transient and mild to moderate in nature. In trials of all designs, adverse events reported by patients receiving Viagra were generally similar. In fixed-dose studies, the incidence of some adverse events increased with dose. The nature of the adverse events in flexible-dose studies, which more closely reflect the recommended dosage regimen, was similar to that for fixed-dose studies. When Viagra was taken as recommended (on an as-needed basis) in flexible-dose, placebo-controlled clinical trials, the following adverse events were reported: Other adverse reactions occurred at a rate of >2%, but equally common on placebo: respiratory tract infection, back pain, flu syndrome, and arthralgia. In fixed-dose studies, dyspepsia (17%) and abnormal vision (11%) were more common at 100 mg than at lower doses. At doses above the recommended dose range, adverse events were similar to those detailed above but generally were reported more frequently. The following events occurred in <2% of patients in controlled clinical trials; a causal relationship to Viagra is uncertain. Reported events include those with a plausible relation to drug use; omitted are minor events and reports too imprecise to be meaningful: Body as a whole: face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injury. Cardiovascular: angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy. Digestive: vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitis. Hemic and Lymphatic: anemia and leukopenia. Metabolic and Nutritional: thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremia. Musculoskeletal: arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis. Nervous: ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesia. Respiratory: asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increased. Skin and Appendages: urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis. Special Senses: sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyes. Urogenital: cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia. Serious cardiovascular, cerebrovascular, and vascular events, including myocardial infarction, sudden cardiac death, ventricular arrhythmia, cerebrovascular hemorrhage, transient ischemic attack, hypertension, subarachnoid and intracerebral hemorrhages, and pulmonary hemorrhage have been reported post-marketing in temporal association with the use of Viagra. Most, but not all, of these patients had preexisting cardiovascular risk factors. Many of these events were reported to occur during or shortly after sexual activity, and a few were reported to occur shortly after the use of Viagra without sexual activity. Others were reported to have occurred hours to days after the use of Viagra and sexual activity. It is not possible to determine whether these events are related directly to Viagra, to sexual activity, to the patient's underlying cardiovascular disease, to a combination of these factors, or to other factors (see for further important cardiovascular information). Cases of sudden decrease or loss of hearing have been reported postmarketing in temporal association with the use of PDE5 inhibitors, including Viagra. In some of the cases, medical conditions and other factors were reported that may have also played a role in the otologic adverse events. In many cases, medical follow-up information was limited. It is not possible to determine whether these reported events are related directly to the use of Viagra, to the patient’s underlying risk factors for hearing loss, a combination of these factors, or to other factors (see ). Nervous: seizure and anxiety. Urogenital: prolonged erection, priapism (see ), and hematuria. Special Senses: diplopia, temporary vision loss/decreased vision, ocular redness or bloodshot appearance, ocular burning, ocular swelling/pressure, increased intraocular pressure, retinal vascular disease or bleeding, vitreous detachment/traction, paramacular edema and epistaxis. Non-arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision, has been reported rarely post-marketing in temporal association with the use of phosphodiesterase type 5 (PDE5) inhibitors, including Viagra. Most, but not all, of these patients had underlying anatomic or vascular risk factors for developing NAION, including but not necessarily limited to: low cup to disc ratio ("crowded disc"), age over 50, diabetes, hypertension, coronary artery disease, hyperlipidemia and smoking. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors, to the patient's underlying vascular risk factors or anatomical defects, to a combination of these factors, or to other factors (see ). In studies with healthy volunteers of single doses up to 800 mg, adverse events were similar to those seen at lower doses but incidence rates were increased. In cases of overdose, standard supportive measures should be adopted as required. Renal dialysis is not expected to accelerate clearance as sildenafil is highly bound to plasma proteins and it is not eliminated in the urine. For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, Viagra may be taken anywhere from 4 hours to 0.5 hour before sexual activity. Based on effectiveness and toleration, the dose may be increased to a maximum recommended dose of 100 mg or decreased to 25 mg. The maximum recommended dosing frequency is once per day. The following factors are associated with increased plasma levels of sildenafil: age >65 (40% increase in AUC), hepatic impairment (e.g., cirrhosis, 80%), severe renal impairment (creatinine clearance <30 mL/min, 100%), and concomitant use of potent cytochrome P450 3A4 inhibitors [ketoconazole, itraconazole, erythromycin (182%), saquinavir (210%)]. Since higher plasma levels may increase both the efficacy and incidence of adverse events, a starting dose of 25 mg should be considered in these patients. Ritonavir greatly increased the systemic level of sildenafil in a study of healthy, non-HIV infected volunteers (11-fold increase in AUC, see .) Based on these pharmacokinetic data, it is recommended not to exceed a maximum single dose of 25 mg of Viagra in a 48 hour period. Viagra was shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors or nitrates in any form is therefore contraindicated. When Viagra is co-administered with an alpha-blocker, patients should be stable on alpha-blocker therapy prior to initiating Viagra treatment and Viagra should be initiated at the lowest dose (see ). Viagra (sildenafil citrate) is supplied as blue, film-coated, rounded-diamond-shaped tablets containing sildenafil citrate equivalent to the nominally indicated amount of sildenafil as follows: Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F) [see USP Controlled Room Temperature]. LAB-0221-8.0 ®. It is not meant to take the place of your doctor's instructions. Read this information carefully before you start taking Viagra. Ask your doctor or pharmacist if you do not understand any of this information or if you want to know more about Viagra. This medicine can help many men when it is used as prescribed by their doctors. However, Viagra is not for everyone. It is intended for use only by men who have a condition called erectile dysfunction. Viagra must never be used by men who are taking medicines that contain nitrates of any kind, at any time. This includes nitroglycerin. If you take Viagra with any nitrate medicine your blood pressure could suddenly drop to an unsafe or life threatening level. • WHAT IS Viagra? Viagra is a pill used to treat erectile dysfunction (impotence) in men. It can help many men who have erectile dysfunction get and keep an erection when they become sexually excited (stimulated). You will not get an erection just by taking this medicine. Viagra helps a man with erectile dysfunction get an erection only when he is sexually excited. When a man is sexually excited, the penis rapidly fills with more blood than usual. The penis then expands and hardens. This is called an erection. After the man is done having sex, this extra blood flows out of the penis back into the body. The erection goes away. If an erection lasts for a long time (more than 6 hours), it can permanently damage your penis. You should call a doctor immediately if you ever have a prolonged erection that lasts more than 4 hours. Some conditions and medicines interfere with this natural erection process. The penis cannot fill with enough blood. The man cannot have an erection. This is called erectile dysfunction if it becomes a frequent problem. During sex, your heart works harder. Therefore sexual activity may not be advisable for people who have heart problems. Before you start any treatment for erectile dysfunction, ask your doctor if your heart is healthy enough to handle the extra strain of having sex. If you have chest pains, dizziness or nausea during sex, stop having sex and immediately tell your doctor you have had this problem. Viagra enables many men with erectile dysfunction to respond to sexual stimulation. When a man is sexually excited, Viagra helps the penis fill with enough blood to cause an erection. After sex is over, the erection goes away. As noted above (How Sex Affects the Body), ask your doctor if your heart is healthy enough for sexual activity. If you take any medicines that contain nitrates – either regularly or as needed – you should never take Viagra. If you take Viagra with any nitrate medicine or recreational drug containing nitrates, your blood pressure could suddenly drop to an unsafe level. You could get dizzy, faint, or even have a heart attack or stroke. Nitrates are found in many prescription medicines that are used to treat angina (chest pain due to heart disease) such as: nitroglycerin (sprays, ointments, skin patches or pastes, and tablets that are swallowed or dissolved in the mouth) isosorbide mononitrate and isosorbide dinitrate (tablets that are swallowed, chewed, or dissolved in the mouth) Nitrates are also found in recreational drugs such as amyl nitrate or nitrite ("poppers"). If you are not sure if any of your medicines contain nitrates, or if you do not understand what nitrates are, ask your doctor or pharmacist. Viagra is only for patients with erectile dysfunction. Viagra is not for newborns, children, or women. Do not let anyone else take your Viagra. Viagra must be used only under a doctor's supervision. Viagra does not cure erectile dysfunction. It is a treatment for erectile dysfunction. Viagra does not protect you or your partner from getting sexually transmitted diseases, including HIV—the virus that causes AIDS. Viagra is not a hormone or an aphrodisiac. Only your doctor can decide if Viagra is right for you. Viagra can cause mild, temporary lowering of your blood pressure. You will need to have a thorough medical exam to diagnose your erectile dysfunction and to find out if you can safely take Viagra alone or with your other medicines. Your doctor should determine if your heart is healthy enough to handle the extra strain of having sex. have ever had any heart problems (e.g., angina, chest pain, heart failure, irregular heart beats, heart attack or narrowing of the aortic valve) have ever had any blood problems, including sickle cell anemia or leukemia have a deformed penis, Peyronie's disease, or ever had an erection that lasted more than 4 hours Some medicines can change the way Viagra works. Tell your doctor about any medicines you are taking. Do not start or stop taking any medicines before checking with your doctor or pharmacist. This includes prescription and nonprescription medicines or remedies: Remember, Viagra should never be used with medicines that contain nitrates (see Viagra Is Not for Everyone). If you are taking medicines called alpha-blockers for the treatment of high blood pressure or prostate problems, your blood pressure could suddenly drop. You could get dizzy or faint. If you are taking a protease inhibitor, your dose may be adjusted (please see Finding the Right Dose for You). Viagra should not be used with any other medical treatments that cause erections. These treatments include pills, medicines that are injected or inserted into the penis, implants or vacuum pumps. Viagra comes in different doses (25 mg, 50 mg and 100 mg). If you do not get the results you expect, talk with your doctor. You and your doctor can determine the dose that works best for you. Do not take more Viagra than your doctor prescribes. If you think you need a larger dose of Viagra, check with your doctor. Viagra should not be taken more than once a day. Your doctor may prescribe a lower dose of Viagra in certain circumstances. For example: If you are older than age 65, or have serious liver or kidney problems, your doctor may start you at the lowest dose (25 mg) of Viagra. If you are taking protease inhibitors, such as for the treatment of HIV, your doctor may recommend a 25 mg dose and may limit you to a maximum single dose of 25 mg of Viagra in a 48 hour period. If you have prostate problems or high blood pressure for which you take medicines called alpha blockers, your doctor may start you on a lower dose of Viagra. Take Viagra about one hour before you plan to have sex. Beginning in about 30 min