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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.

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.

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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.  generic sildenafil citrate 90x100mg

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This medicine is a phosphodiesterase inhibitor used to treat sexual function problems such as impotence or erectile dysfunction. In combination with sexual stimulation, this medicine works by helping the blood flow into the penis to achieve and maintain an erection. This medicine is not intended for use in women or children. This medicine will not protect against sexually transmitted diseases including HIV infection. Use "safe sex" practices such as latex condoms. Contact your doctor or pharmacist for more details. Some medicines or medical conditions may interact with this medicine. INFORM YOUR DOCTOR OR PHARMACIST of all prescription and over-the-counter medicine that you are taking. DO NOT TAKE THIS MEDICINE if you are taking any form of nitroglycerin, (such as tablet, patch, or ointment dose forms) or other nitrates (such as isosorbide), nitroprusside (or any "nitric oxide donor" medicine), or recreational drugs called "poppers" containing amyl or butyl nitrate because very serious interactions may occur. If you are not sure whether a certain medicine is a nitrate, contact your doctor or pharmacist. If you are currently using any of these medicines, tell your doctor or pharmacist before using sildenafil. ADDITIONAL MONITORING OF YOUR DOSE OR CONDITION may be needed if you are taking other medicines for impotence, antifungals (such as itraconazole or ketoconazole), cimetidine, delavirdine, erythromycin, mibefradil, or rifampin. If you are taking an HIV protease inhibitor (such as ritonavir or saquinavir), do not take more than a 25 mg dose of sildenafil in a 48-hour period. If you are taking more than a 25 mg dose of sildenafil and are also taking an alpha-blocker medicine (such as doxazosin, prazosin, or terazosin) for various conditions (such as enlarged prostate), separate the time between taking these medicines by more than 4 hours. DO NOT START OR STOP any medicine without doctor or pharmacist approval. Inform your doctor of any other medical conditions including penis conditions (such as angulation, fibrosis/scarring, or Peyronie's disease), history of painful/prolonged erection (priapism), sickle cell anemia, blood system cancers (such as leukemia or myeloma), vision problems (such as retina diseases like retinitis pigmentosa) or history of vision loss, kidney or liver disease, bleeding disorders, active stomach ulcers, heart problems (such as recent heart attack or irregular heartbeat within past 6 months, heart failure, coronary artery disease with unstable angina, aortic stenosis or idiopathic hypertrophic subaortic stenosis), recent stroke within past 6 months, very high or low blood pressure, or allergies. Contact your doctor or pharmacist if you have any questions or concerns about taking this medicine. Follow the directions for using this medicine provided by your doctor. An additional patient information leaflet is available with this medicine. Read it carefully. Ask your doctor, nurse, or pharmacist any questions that you may have about this medicine. TAKE THIS MEDICINE by mouth as needed between four hours and one-half hour before sexual activity (about 1 hour before is most effective); or take as directed by your doctor. DO NOT TAKE THIS MEDICINE more often than once daily as needed. A high fat meal may delay the time of onset of this medicine. Your dosage is based on your medical condition, your response to therapy, and other medicines you are taking. Consult your doctor or pharmacist for more information. STORE THIS MEDICINE at room temperature 77 degrees F (25 degrees C) in a tightly-closed container, away from heat, moisture, and light. Brief storage between 59 and 86 degrees F (15 and 30 degrees C) is permitted. DO NOT TAKE THIS MEDICINE if you have had an allergic reaction to it in the past or to any other ingredient that is found in it. THIS MEDICINE MAY CAUSE VISION CHANGES. DO NOT DRIVE, OPERATE MACHINERY, OR DO ANYTHING ELSE THAT COULD BE DANGEROUS until you know how you react to this medicine. Using this medicine alone, with other medicines, or with alcohol may lessen your ability to drive or to perform other potentially dangerous tasks. TO MINIMIZE DIZZINESS OR LIGHTHEADEDNESS, sit up or stand slowly when rising from a seated or lying position. Your dose is based on your medical condition, response to therapy, and the other medicines you are taking. DO NOT EXCEED THE RECOMMENDED DOSE without checking with your doctor. Rarely, this medicine may change heart rhythm, especially if taken with other medicines that can change the heart rhythm. This change in heart rhythm can result in serious, rarely fatal, irregular heartbeats. Ask your doctor for more information and if you should stop taking any of your other medicines to reduce the risk of this side effect. BEFORE YOU BEGIN TAKING ANY NEW MEDICINE, either prescription or over-the-counter, check with your doctor or pharmacist. CAUTION IS ADVISED WHEN USING THIS MEDICINE IN THE ELDERLY because they may be more sensitive to the side effects of this medicine. THIS MEDICINE SHOULD NOT BE USED IN WOMEN OR CHILDREN. SIDE EFFECTS that may occur while taking this medicine include headache, flushing, stomach upset, heartburn, nasal stuffiness, diarrhea, dizziness, or lightheadedness. Vision changes such as increased sensitivity to light, blurred vision, or impaired blue/green color discrimination may also occur. If these continue or are bothersome, check with your doctor or pharmacist. CONTACT YOUR DOCTOR IMMEDIATELY if you experience vision loss in one or both eyes, hearing loss, ringing in the ears, or severe or persistent dizziness. Sexual activity may put extra strain on your heart, especially if you have heart problems. If you have heart problems and experience any serious side effects while having sex, stop having sex and tell your doctor immediately. These side effects include severe dizziness, fainting, chest pain, or nausea. In the unlikely event that you have a painful or prolonged erection (lasting more than 4 hours), stop using this medicine and seek immediate medical attention or permanent problems could occur. AN ALLERGIC REACTION TO THIS MEDICINE is unlikely, but seek immediate medical attention if it occurs. Symptoms of an allergic reaction include rash, itching, unusual swelling, severe dizziness, or trouble breathing. If you notice other effects not listed above, contact your doctor, nurse, or pharmacist. If overdose is suspected, contact your local poison control center or emergency room immediately. Symptoms of overdose may include severe dizziness, fainting, or prolonged erection. If your symptoms do not improve or if they become worse, check with your doctor. DO NOT SHARE THIS MEDICINE with others for whom it was not prescribed, since they may have a problem that is not effectively treated with this medicine, or they may have a condition that is complicated by this medicine. DO NOT USE THIS MEDICINE for other health conditions. KEEP THIS MEDICINE out of the reach of children and pets. IF USING THIS MEDICINE FOR AN EXTENDED PERIOD OF TIME, obtain refills before your supply runs out. Copyright 2008 Wolters Kluwer Health, Inc. - This information is not intended to substitute for professional medical advice. Be sure to contact your physician, pharmacist or other health care provider for more information about this medication. By searching these web site pages, you agree to our online pharmacy viagra 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.levitra online prescriptioncom viagra Viagra receives much cynicism about its effects and usefulness, despite the facts that all the evidence suggests otherwise, and there are thousands of satisfied users world wide. Most generally acknowledged as a cure for male erectile dysfunction, it has been documented that Viagra does more than just aid a man's erection. Various reports from numerous areas of health research worldwide point to other possible health benefits of Viagra. For instance, Saarland discovered that Viagra can reduce symptoms of Raynaud's phenomenon, a circulatory disorder. The hormonal stress normally exerted on the human heart has been noted to be decreased in men who take Viagra. When conducted with mice, the testing was more noticeable, Viagra having the tendency to avert harmful and long term effects of chronic hypertension on their heart. The study, lead by the John Hopkins research team, found that there is potential benefits for the treatment of pulmonary hypertension, linked in with how viagra dilates genital blood vessels. After testing on humans, abnormally high heart rates appeared to reduce by 50% after taking sildenafil (Viagra). Current evidence indicates health benefits of Viagra, in addition to the most commonly associated benefit of curing erectile dysfunction. 5 print sildenafil citrate order form However discomfiting the commercials, the -- on March 27, 1998 -- is a landmark day in the history of sex. It seemed at the time like a biomedical revolution was upon us all, and about five minutes after word of the magical med went global, the question first was asked: Where is the women's version of Viagra? The short answer: They're still working on it. A bunch of companies have tried and failed to create "pink Viagra," as it's often called. Other companies have drugs in late stages of clinical testing, including a gel that recently began a make-or-break nationwide study with several thousand women. Give us five years, maybe less, say the most optimistic researchers and doctors. Though it's unclear exactly how many women would ask for a prescription, no one doubts that the first company that gets to market a remedy for female sexual dysfunction, as it's formally known, will earn a fortune. But as this race reaches what could be its final lap, not all of the spectators are cheering. Some, in fact, are booing as loudly as they can. A modest-size but fervent group of psychologists, academics and public health advocates contend that FSD isn't an authentic medical condition, or at least not the sort of problem that should be treated with drugs. These aren't the obtuse male physicians who for decades have been telling women distressed by their lack of libido that "it's all in your head." The anti-FSD crowd is mostly women, many of them self-described feminists. The most prominent is Leonore Tiefer, a psychotherapist and clinical associate professor at , who has long decried what she calls "the medicalization of women's sexuality." "Drug companies want to say to women, 'You don't need to know anything; you can have the satisfying sex life that you seek -- people dancing on TV, the whole bit -- without knowing anything. Just ask your doctor,' " she says. "I resent that, because there are specific harms that come from being ignorant and dependent in the world we live in. There may be lots of people who aren't interested in sex, but is there a medical reason for that, and do we diagnose that?" Tiefer's critique centers, in part, on the way that pink Viagra is sure to be marketed -- with ads day and night, suggesting that women who aren't feeling frisky have a medical problem. She and her allies -- organized as the New View Campaign -- are also galled that so much money and media attention are heaped on the lust drug, even before it exists, when for many women the solution to their libido problems isn't that exotic. Maybe they have a partner who hasn't a clue about technique.Maybe they're stressed out. Maybe they can't possibly get in the mood because they're so busy raising children. Therapy, counseling, even free day care, says the New View Campaign, might do more for women's sex lives than any drug company ever could. "People walk out of their doctors' offices with a prescription in hand 85 percent of the time," says Meika Loe, the author of "The Rise of Viagra" and a New View endorser. "But health insurers won't pay if you want to talk to a counselor or if you need advice about how to communicate your sexual desires. We've got a health-care system that is almost entirely focused on medical solutions." On the other side of the FSD divide, allied with the pharmaceutical companies, is a group of physicians who are prescribing off-label treatments for women vexed by their sex lives. (Off-label means the drug hasn't been approved by the FDA for that specific treatment.) The highest-profile of the bunch is Irwin Goldstein, the director of sexual medicine at San Diego's Alvarado Hospital. He and Tiefer have debated the topic of FSD for a decade, but as far as he's concerned, there's really nothing to discuss. He's been using hormones to treat women, and he'll happily put you in touch with patients who will rhapsodize about the results. Women like Virginia, a 60-year-old native of and an artist who, for privacy reasons, asked that her last name be omitted. She'd spent years asking doctors for medical help to boost her sex drive, which had once been voracious. All of them, she says, "rolled their eyes and harrumphed and tried to change the subject." "But when I was younger, a really strong libido was just part of who I was," she goes on. "Losing that was like losing a good friend." Three years ago, she heard Goldstein interviewed on . Within weeks she flew to , the site of his practice at the time, and she soon was taking several hormones. There was tinkering with the combination and the dosage, but a few weeks later she suddenly felt "perky" -- more confident about herself as a sexual being and more attractive. She also started having better sex. 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. buy viagra in jersey According to research on mice, Viagra may play a prominent role in reversing growth abnormalities in the heart. Researchers are of the opinion that Viagra reversed the abnormal growth of heart muscles and restored normal heart function to mice with enlarged hearts. A larger-than-normal heart is quite a serious medical condition. Commonly termed as hypertrophy, it is a main feature of heart failure and can be fatal. The condition develops because of chronically uncontrolled high blood pressure. This forces the heart to pump harder to satisfy the body's requirements; to adapt to these high pressures, the muscles of the heart enlarge. Individuals with hypertrophy (enlarged hearts) have a much higher probability of developing heart disease, heart failure or sudden cardiac death. The study states that Viagra may turn out to be an effective treatment for a chronic heart condition. The next point of action will be to conduct research to see if the Viagra will have the same advantageous effect in humans that it had shown in mice. It is also has come to the conclusion that the enzyme pathway blocked by sildenafil (PDE5A), never before known to play a prominent part in the heart, is charged when the heart is exposed to pressure stress and hypertrophied. The findings of the study provide a few of the strongest proofs that blocking the heart's adaptive response to hypertrophy does not harm its function but may improve it. Researchers come to the conclusion that heart function, normally measured by pressure/volume analysis of the muscle's ability to contract and pump blood, surprisingly improved after hypertrophy had been halted and treated. While researchers were of the view that that hypertrophy was an adaptive feedback to pressure stress, the functional gains lasted despite the heart's continued exposure to high blood pressure. Improvements were evident in more than ten measures of heart function, taking into account heart relaxation, cardiac output and heart contractility (which enhanced by staggering 40 percent). Furthermore, these types of improvements were evident even when therapy was deferred and initiated two weeks after hypertrophy had already developed. The study clearly demonstrates that sildenafil can eliminate hypertrophy. Its effects can not only be halted, but also reversed. The findings provide a better understanding of the biological pathways and suggest possible therapies using sildenafil. It has the added advantage of already being termed safe and effective for other medical purposes. cheap viagra online In the U.S.— Sildenafil (sil-DEN-a-fil) belongs to a group of medicines that delay the enzymes called phosphodiesterases from working too quickly. The penis is one of the areas where these enzymes work. Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). By controlling the enzyme phosphodiesterase, sildenafil helps to maintain an erection that is produced when the penis is stroked. Without physical action to the penis, such as that occurring during sexual intercourse, sildenafil will not work to cause an erection. Sildenafil is also used to treat the symptoms of pulmonary arterial hypertension. This is the high blood pressure that occurs in the main artery that carries blood from the right side of the heart (the ventricle) to the lungs. When the smaller blood vessels in the lungs become more resistant to blood flow, the right ventricle must work harder to pump enough blood through the lungs. Sildenafil helps by increasing the supply of blood to the lungs and reducing the workload of the heart. This medicine is available only with your doctor's prescription, in the following dosage form(s): Tablets (U.S.) In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For sildenafil, the following should be considered: Tell your doctor if you have ever had any unusual or allergic reaction to sildenafil. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes. Sildenafil is not indicated for use in women. Sildenafil has not been studied in pregnant women. However, sildenafil has not been shown to cause birth defects or other problems in animal studies. It is not known whether sildenafil passes into breast milk. Sildenafil is not indicated for use in women for erectile dysfunction. Mothers who are taking this medicine for pulmonary arterial hypertension and who wish to breast-feed should discuss this with their doctor. Elderly people are especially sensitive to the effects of sildenafil, which may increase their chance of having side effects. Patients 65 years of age and older who are taking this medicine for erectile dysfunction are started on a low dose, 25 mg, of sildenafil. Patients who are taking this medicine for pulmonary arterial hypertension may also need to be started at a lower dose. The dose may be increased by a doctor as needed and tolerated. Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking sildenafil, it is especially important that your health care professional know if you are taking any of the following: Alpha-blockers (medicine for high blood pressure—Sildenafil when taken together with an alpha-blocker medicine may cause very low blood pressure. Sildenafil doses above 25 mg should not be taken within 4 hours of taking an alpha-blocker medicine. Bosentan (e.g., Tracleer)—May increase amounts of bosentan in the body Cimetidine (e.g., Tagamet) Erythromycin (e.g., E.E.S. or Ery-Tab) Itraconazole (e.g., Sporanox) Ketaconazole (e.g., Nizoral) Mibefradil (e.g., Posicor) Ritonavir (e.g., Norvir) Saquinavir (e.g., Fortovase or Invirase)—These medicines may increase the unwanted effects of sildenafil, unless lower starting doses of sildenafil are used Erectile dysfunction medicines—These medicines should not be used at the same time as sildenafil because the safety of using these medicines in combination has not been proven. Nitrates, such as nitroglycerin (e.g., Nitrostat or Transderm-Nitro)—Sildenafil increases the lowering of blood pressure by nitrates too much and their use together is not recommended The presence of other medical problems may affect the use of sildenafil. Make sure you tell your doctor if you have any other medical problems, especially: Smoking—These conditions may increase risk for a serious eye problem called NAION. Heart attack, history of (within the last 6 months) or Stroke, history of (within the last 6 months)—Chance of problems occurring may be increased Abnormal penis, including curved penis and birth defects of the penis—Chance of problems occurring may be increased Retinitis pigmentosa—Chance of problems occurring may be increased. It is not known if the medicine is safe for use in these patients Conditions causing thickened blood or slower blood flow, including leukemia; multiple myeloma (tumors of the bone marrow); or polycythemia, sickle cell disease, and thrombocythemia (blood problems) or Priapism (history of)—Although sildenafil does not cause priapism (erection lasting longer than 6 hours), patients with these conditions have an increased risk of priapism and it could occur while using sildenafil Heart or blood disease—Sexual activity increases the heart rate and blood flow and can increase the chance of problems occurring for some patients who use any type of medicine, including sildenafil, that increases sexual ability Liver problems (severe)—Chance of problems occurring may be increased. Lower starting doses may be used and doses increased as needed and as tolerated NAION (serious eye condition) in one or both eyes, previously—May increase your chance of getting NAION again. Special patient directions come with sildenafil. . This medicine usually begins to work within 30 minutes after taking it for erectile dysfunction. It continues to work for up to 4 hours, although its action is usually less after 2 hours. The dose of sildenafil will be different for different patients. . The following information includes only the average doses of sildenafil. If your dose is different, do not change it unless your doctor tells you to do so. Adults up to 65 years of age—50 mg as a single dose no more than once a day, 1 hour before sexual intercourse. Alternatively, the medicine may be taken 30 minutes to 4 hours before sexual intercourse. If needed, your doctor may increase your daily dose to 100 mg or decrease your daily dose to 25 mg. Adults 65 years of age and older—25 mg as a single dose no more than once a day, 1 hour before sexual intercourse. Alternatively, the medicine may be taken 30 minutes to 4 hours before sexual intercourse. If needed, your doctor may increase your daily dose. 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 Adults—20 mg three times per day. Each dose should be taken about 4 to 6 hours apart and can be taken with or without food. Children—Use and dose must be determined by your doctor. Keep out of the reach of children. Store away from heat and direct light. Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down. Keep the medicine from freezing. Do not refrigerate. Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children. Sildenafil has not been studied with other medicines used for treatment of erectile dysfunction. Presently, using them together is not recommended . . If you need emergency medical care for a heart problem, it is important that your healthcare provider knows when you last took sildenafil. . Do not use more of it and do not use it more often than your doctor ordered. If too much is used, the chance of side effects is increased. If you experience a prolonged or painful erection for 4 hours or more, contact your doctor immediately. This condition may require prompt medical treatment to prevent tissue damage of the penis and possible permanent impotence. This medicine does not protect you against sexually transmitted diseases. Use protective measures and ask your doctor if you have any questions about this. It is important to tell your doctor about any heart problems you may have now or may have had in the past. This medicine can cause serious side effects in patients with heart problems. If you experience sudden loss of vision in one or both eyes, stop using sildenafil and contact your doctor immediately. Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if any of the following side effects continue or are bothersome: Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor. The information contained in the Thomson Healthcare (Micromedex) products as delivered by Drugs.com is intended as an educational aid only. It is not intended as medical advice for individual conditions or treatment. It is not a substitute for a medical exam, nor does it replace the need for services provided by medical professionals. 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Thomson Healthcare does not assume any responsibility or risk for your use of the Thomson Healthcare products. Nuts, crocodiles and witch trials may seem to have little to do with Viagra -- but at one time or another, they've all been employed against erectile dysfunction. For centuries, doctors struggled to pinpoint the causes of male impotence, blaming such factors as stress, diet, the wrath of deities and unattractive women. Ancient Greek physician Hippocrates attributed impotence to horseback riding; one of his contemporaries placed the blame on childhood trauma; Egyptians to evil spells. The ancients also left behind an imaginative array of remedies: snacks of almonds, pistachios, dates, currant juice and bird eggs in Persia; a mix of sesame, lentils, rice and sugar cane juice in ancient India -- or goat testicles boiled in milk or butter and boiled alligator testes rubbed on the feet. The Egyptians were more direct, smearing remedies (such as crocodile hearts and wood oil) directly on the penis. In the Islamic empire, impotence was sometimes blamed on an imbalance in the four fluids, or humors, thought to course through the body. Doctors advised men to avoid sex after meals, in the bathroom and with old or unappealing partners. In medieval Europe, impotent men believed they were under spells cast by witches, but also blamed their wives. Impotence was grounds for divorce. In the Victorian era, many thought impotence was due to a depletion of sperm. Doctors cautioned against masturbation (a "waste" of sperm) and prescribed quinine, opium, digitalis and bleeding, to no avail. In the late 1800s, French professor of medicine Charles Edouard Brown-Sequard proposed that injections of animal sperm might restore vitality. He tested the theory by injecting himself with an extract of dog and guinea pig testicles. His colleagues, who agreed the professor looked good for a man of 72, agreed to test the extracts on their patients. Soon the treatment, organotherapy, was all the rage. Starting in the late 1910s, a few doctors went a step further, deciding to transplant whole testicles. In France, Serge Voronoff transplanted monkey testicles into the nether regions of more than 1,000 old men. In Kansas, John Brinkley ran a hospital that specialized in grafting goat testicles onto patients. At a California prison, Leo Stanley gave older inmates testicles of younger, executed prisoners. Although many men claimed to feel rejuvenated by their testicular shots and transplants, few recovered their virility, and researchers continued their search. In the 1930s doctors experimented with surgical adjustment of penile muscles. In the 1940s and 1950s, they tried implants, inspired by the penile bones many animals have. In the 1960s, an effective option finally arrived. A Georgia tire serviceman began work on a vacuum pump to treat his own impotence, which was ultimately approved by the Food and Drug Administration in 1982. The pump appeared just as several researchers began to identify drug treatments for impotence, albeit few with the showmanship exhibited by British doctor Giles Brindley. At a 1983 urology meeting, Brindley injected himself with a drug, phentolamine -- then took the stage, dropped his pants and shared his erection with his colleagues. Brindley injected 33 drugs in his penis before finding one that worked, which may have rendered him slightly envious of the discoverers of Viagra. British researchers Ian Osterloh and Gill Samuels were developing a drug to improve blood flow to the heart when they realized that the drug, sildenafil citrate, was much more effective at improving blood flow to the penis -- and causing erections. In Viagra's first month on the market, doctors wrote well over 500,000 prescriptions. Considering men's history of options -- crocodile hearts, prayer, testicular shots and grafts -- perhaps the blue pill's lasting popularity should come as no surprise. buy cheap purchase uk viagra 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 cheap viagra Viagra turns 10 this month, and didn't time just fly? It seems like only yesterday we started guffawing at the Symbolism for Dummies ads on TV for the little blue pill and its "erectile dysfunction" rivals -- footballs tossed through tires, faucets erupting. The spots ended with a list of potential side effects that sounded like a satire of potential side effects. "More than four hours?" we winced. "Ouch." However discomfiting the commercials, the Food and Drug Administration (FDA) approval of Viagra -- on March 27, 1998 -- is a landmark day in the history of sex. It seemed at the time like a biomedical revolution was upon us all, and about five minutes after word of the magical med went global, the question first was asked: Where is the women's version of Viagra? The short answer: They're still working on it. A bunch of companies have tried and failed to create "pink Viagra," as it's often called. Other companies have drugs in late stages of clinical testing, including a gel that recently began a make-or-break nationwide study with several thousand women. Give us five years, maybe less, say the most optimistic researchers and doctors. Though it's unclear exactly how many women would ask for a prescription, no one doubts that the first company that gets to market a remedy for female sexual dysfunction (FSD), as it's formally known, will earn a fortune. But as this race reaches what could be its final lap, not all of the spectators are cheering. Some, in fact, are booing as loudly as they can. A modest-size but fervent group of psychologists, academics and public health advocates contend that FSD isn't an authentic medical condition, or at least not the sort of problem that should be treated with drugs. These aren't the obtuse male physicians who for decades have been telling women distressed by their lack of libido that "it's all in your head." The anti-FSD crowd is mostly women, many of them self-described feminists. The most prominent is Leonore Tiefer, a psychotherapist and clinical associate professor at New York University, who has long decried what she calls "the medicalization of women's sexuality." "Drug companies want to say to women, 'You don't need to know anything; you can have the satisfying sex life that you seek -- people dancing on TV, the whole bit -- without knowing anything. Just ask your doctor,' " she says. "I resent that, because there are specific harms that come from being ignorant and dependent in the world we live in. There may be lots of people who aren't interested in sex, but is there a medical reason for that, and do we diagnose that?" online purchase viagra Generic "Viagra" is a substance that is used to treat erectile dysfunction. Generic "Viagra" relaxes the smooth muscle of the penis to allow increased blood flow and erection. It belongs to the family of drugs called phosphodiesterase inhibitors. Generic "Viagra" enables men with ED to respond to sexual stimulation. When a man is sexually excited, the arteries in his penis relax and widen. This allows more blood to flow into the penis. The increased blood flow causes the penis to become hard and erect. The veins that normally carry blood away from the penis then become compressed. This restricts the blood flow out of the penis. With more blood flowing in and less flowing out, the penis enlarges, resulting in an erection. Sometimes the nerves or blood vessels that are part of this process don't work properly. If this happens, a man may not be able to get or keep an erection. Generic "Viagra" increases blood flow to the penis, so that when a man is sexually excited, he can consistently get and keep an erection. When he is done having sex, the erection goes away. Inactive Ingredients: magnesium stearate, hypromellose, titanium dioxide, lactose, microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, triacetin, and FD & C Blue #2 aluminum lake. What is Generic "Viagra" PRESCRIBED For? Generic "Viagra" is an effective treatment for male erectile dysfunction, or ED. This is also known as impotence. Generic "Viagra" is a little blue pill you take only when you want to have sex. Generic "Viagra" helps men consistently get and keep an erection when they become sexually stimulated. How Should I Take Generic "Viagra"? Take Generic "Viagra" exactly as it was prescribed for you. Do not take it in larger doses or for longer than recommended by your doctor. Revatio is usually taken three times each day, about 4 to 6 hours apart. Generic "Viagra" is usually taken only when needed, 30 minutes to 1 hour before sexual activity. You may take it up to 4 hours before sexual activity. Do not take Generic "Viagra" more than once per day. Generic "Viagra" can help you have an erection when sexual stimulation occurs. An erection will not occur just by taking a pill. Follow your doctor's instructions. If you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw during sexual activity, stop and call your doctor right away. You could be having a serious side effect of Generic "Viagra". Keep out of the reach and sight of children. Do not store above 30°C. Keep tablets in the original package, protected from moisture. Do not use after the expiry date stated on the pack. What are the CONTRAINDICATIONS for taking Generic "Viagra"? Before taking Generic "Viagra", tell your doctor if you have had a heart attack, stroke, or life-threatening irregular heartbeats within the last six months; have a history of heart failure; have coronary artery disease; have angina; have high or low blood pressure; have liver problems; have kidney problems; have ever had blood problems, including sickle cell anemia or leukemia; have a bleeding disorder; have a stomach ulcer; have retinitis pigmentosa (an inherited condition of the eye); have a physical deformity of the penis such as Peyronie's disease; have a condition that could lead to prolonged and painful erections, such as a tumor of the bone marrow, sickle cell anemia, or leukemia; or are taking another medicine to treat impotence. You may not be able to take Generic "Viagra", or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above. Although Generic "Viagra" is not indicated for use by women, it is in the FDA pregnancy category B. This means that Generic "Viagra" is not expected to be harmful to an unborn baby. Women should not take Generic "Viagra". It is not known whether Generic "Viagra" passes into breast milk. If you are over 65 years of age, you may be more likely to experience side effects from Generic "Viagra". Your doctor may prescribe a lower dose of this medication. What Happens if I MISS A DOSE? Generic "Viagra" is used as need. So, you are not likely to miss a dose. What Happens if I OVERDOSE? Seek emergency medical attention. Symptoms of a Generic "Viagra" overdose are not known, but are likely to include chest pain, dizziness, an irregular heartbeat, and swelling of the ankles or legs. What are the possible SIDE EFFECTS of Generic Viagra"? Like all medicines, Generic "Viagra" can have side effects. These effects are normally mild to moderate in nature. The most common undesirable effects are headache and facial flushing. Less commonly reported undesirable effects are indigestion, dizziness, stuffy nose and effects on vision including colour tinge to vision, increased brightness of light or blurred vision). Muscle aches can occur if Generic "Viagra" is taken more frequently than once a day. Rarely, prolonged and sometimes painful erections have been reported after taking Generic "Viagra". If you have such an erection which lasts continuously for more than 4 hours, you should contact a doctor immediately. Rarely, hypersensitivity reactions (including skin rashes) have been reported. Heart attack, stroke, irregular heart beats, and death have been reported rarely in men taking Generic "Viagra". What other drugs can INTERACT with Generic "Viagra"? Please inform your doctor or pharmacist if you are taking or have taken recently other medicines, even those not prescribed. Generic "Viagra" tablets may interfere with some medicines, especially those used to treat chest pain. In the event of a medical emergency, you should tell anyone treating your condition that you have taken Generic "Viagra". Do not take - Generic "Viagra" with other medicines unless your doctor tells you that you can. Generic "Viagra" may cause a serious increase in the effects of medicines called nitrates, and nitric oxide donors such as amyl nitrite ("poppers"). These are often used for the relief of angina pectoris (or "chest pains"). You should NOT take Generic "Viagra" if you are taking these medicines. If you are taking protease inhibitors, suck as for the treatment of HIV, your doctor may start you on the lowest dose (25 mg) of Generic "Viagra". If you take any medicines that contain nitrates - either regularly or as needed - you should never take Generic "Viagra". If you take Generic "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. Generic "Viagra" is only for patients with erectile dysfunction. Generic "Viagra" is not for newborns, children, or women. Do not let anyone else take your Generic "Viagra". Generic "Viagra" must be used only under a doctor's supervision. 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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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 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 . viagra online order The success of any medical treatment of impotence also depends on the kind of relationship a couple has. If both parties have a strong commitment to renew sexual intimacy and are both willing to cooperate with the treatment, then there is greater likelihood of the sexual dysfunction being addressed easily. Good communication skills are vital in identifying and addressing most problems, even sexual problems. Some couples to choose to be silent about the issue and pretend that nothing is wrong. This is damaging because although in some cases impotence does improve over time, in most cases the cause is a physical condition which needs medical treatment. Ignoring or denying the problem may prolong recovery and reduce the chance of an effective treatment.  . Remember that impotence is not just a �man's problem'. Although it afflicts only men, it affects both men and women. Admitting to each other that there is a problem and that you are both willing to resolve it is a key to effective sex therapy. It takes a certain amount of preparation, tact, skill and courage to be able to effectively discuss this issue with your partner. Research shows that couples who are in love and share a strong commitment to their relationship are the ones who often seek medical treatment and/or psychological counseling, and are in a better position to benefit from it. Couples who also had an active and fully functioning sex life prior to the onset of impotence have better chances of recapturing the sensuality they once enjoyed.  It is also important that despite the problem of impotence, both partners are still sexually attracted to their mate. Couples who have a sense of humor are also more likely to survive the inconveniences of impotence. While impotence is no laughing matter, the ability of couples to laugh together or share a smile seems to contribute to their ability to rise above life's trials. It is also important that partners enrich themselves with knowledge about sexual functioning, impotence and its possible treatments. Up - to - date information can effectively aid couples in their decisions regarding the treatment of the dysfunction. Restored potency is not a quick - fix for underlying personal and relationship problems. Couples have to understand that it may take medical treatment and/or counseling in order to renew the once loving and warm relationship. Although there is no way of predicting the success of a certain treatment, a more positive response and a greater commitment to renewing intimacy increases the likelihood of an effective treatment. Although erectile dysfunction is a male sexual disorder, it does not only affect the male population. Many women find themselves in a relationship with impotent men. Worse, sex life for most of these couples had been active and healthy prior to the setting in of sexual difficulty for the man. A woman therefore has to work together with her partner to restore his sexual health and potency. The following steps are designed to facilitate successful problem - solving: The first step in addressing any problem, even addictions, is to admit that there indeed is a problem. Many couples choose to be silent about the issue even when both are feeling frustrated and disappointed with what's happening. If having intercourse is important to you, tell your partner about it. Don't pretend it doesn't matter. A couple who wants to restore sexual intercourse after a long period of abstinence has physical and psychological factors to consider. A woman who hasn't had sexual activity for a long time may experience vaginal dryness, loss of vaginal muscle tone and painful intercourse. It is also important for these difficulties to be addressed before resuming sexual intercourse. It is equally important for the couple to be aware of sexual changes in men and women due to aging. On the psychological side, lack of sexual desire, especially on a regular basis, may warrant a visit to a psychologist. Problems such as depression accompanying sexual dysfunction in both men and women have to be dealt with. A couple who is more committed to work with their partners to address sexual difficulty issues is more likely to be successful in solving the problem. A woman has to be equally cooperative and involved as her partner is. Although there is no way to predict one's chances of success from a treatment, the more positive one's response is (with the support of his partner), the greater the likelihood that the treatment will be effective. Visit a physician who specializes in the diagnosis and treatment of sexual dysfunction. A variety of tests will be conducted to determine the underlying causes of the problem. The doctor should be able to tell if the problem is caused by physical or psychological factors. Discuss with your physician the possible treatments you can avail. Communication is an effective tool in dealing with challenges in sexual intimacy. It is important that both consider each other's point of view. Prepare to speak your mind but also prepare to listen. Medical care is essential for those experiencing sexual dysfunction. A visit to a physician is also important as sexual dysfunction may serve as an early warning for other diseases. 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. viagra best buy

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FDA has received reports of cases of sudden decreases or loss of hearing following the use of PDE5 inhibitors, Viagra, Levitra, and Cialis for the treatment of erectile dysfunction and Revatio for the treatment of pulmonary arterial hypertension. In some cases, the sudden hearing loss was accompanied by tinnitus and dizziness. Medical follow-up information was often limited for the cases reported postmarketing, which makes it difficult to determine whether these reports are directly related to the use of one of these drugs, an underlying medical condition, or other risk factors for hearing loss, a combination of these factors, or other factors. Sudden hearing loss was also reported in a few patients in clinical trials of these drugs. In response to a request from FDA, the manufacturers of Viagra, Levitra and Cialis have revised the labeling for these products to address the potential risk of sudden hearing loss and to guide patients on what to do if they experience sudden problems with their hearing. FDA is currently working with the sponsor to revise the labeling for Revatio. The approved revised labeling for Viagra, Levitra and Cialis includes a new sections. The revised labeling is available at . This information reflects FDA’s current analysis of data available to FDA concerning this drug. FDA intends to update this sheet when additional information or analyses become available. Includes previous safety information and approval packages.sildenafil in pulmonary hypertension What is Viagra used for? Viagra is used to treat impotence in men. Viagra increases the body’s ability to achieve and maintain an erection during sexual stimulation. Viagra does not protect you from getting sexually transmitted diseases, including HIV. take Viagra? Men who are currently using medicines that contain nitrates, such as nitroglycerin should not use Viagra because taken together they can lower the blood pressure too much. Viagra should not be used by women or children. In patients taking Viagra, several heart-related side effects have been reported, including heart attack, sudden death, irregular heart rhythm, stroke, chest pain, and increased blood pressure. It is not possible to determine whether these events are directly related to Viagra, to sexual activity, to the patient’s heart condition, to a combination of these factors, or to other factors. taking certain medications at the same time (e.g., ketoconazole, itraconazole, erythromycin and saquinavir). In these patients, the recommended starting dose of Viagra is 25 mg. Heart attack, stroke, or life-threatening irregular heart rhythm within the last 6 months Because Viagra lowers blood pressure, your doctor will evaluate your overall medical condition to determine if Viagra, in combination with sexual activity, could adversely affect you. Viagra can cause a rare but serious condition of prolonged erection (priapism). It is important to contact your health care provider immediately if your erection lasts longer than 4 hours. Men for whom sexual activity is inadvisable may not be good candidates for Viagra. Tell your doctor if you are taking protease inhibitors for the treatment of HIV. You should have a complete medical history and exam to determine the cause of your impotence before taking Viagra. Men who have medical conditions that may cause a sustained erection such as sickle cell anemia, leukemia or multiple myeloma or who have an abnormally shaped penis may not be able to take Viagra. There are several medications that are known to interact with Viagra, so be sure to tell your doctor about all medications you are taking including those you can get without a prescription. Viagra has not been studied with other treatments for impotence, so use in combination with other treatments is not recommended. What are some possible side effects of Viagra? a complete list of side effects reported with Viagra. Your health care provider can discuss with you a more complete list of side effects.) ). The following is a listing of the most common side effects Visual changes such as mild and temporary changes in blue/green colors or increased sensitivity to light. For more detailed information about Viagra, ask your health care provider. levitra versus viagra Is Viagra the Answer for you ? Viagra is not simply a sex pill ...learn its various properties is a pill that not only helps cure erectile dysnfunction but also makes the act of sex more fulfilling. now and know personally how it can help you. Viagra is perhaps one of the most notorious medicines in the market. Considering how integral it is for men's health, psychologically and socially, its funny to note that social and cultural hang-ups still survive in the 21st Century making Viagra, a simple medicine, seem to be a 'drug' that is not mentioned in polite circles. Viagra, is a drug or impotence. Sildenafil is available by prescription only. Viagra can only stimulate if a man is sexually excited. The question is when isn't he sexually excited? Viagra is a medicine, much like Asprin and Panadol that people take to treat their health problems. Erectile Dysfunction is a health problem faced by men. It is prescribed by doctors to help men with erectile problems which can be caused due to age, stress, social pressures or other physiological and psychological reasons. Viagra is not, contrary to popular perception, a sex pill that will help you get bigger erections, act as a love enhancer or protect you against sexually transmitted disease. Viagra is a pill that contains Sildenafil Citrate a chemical that helps treat impotence. Sildenafil Citrate is available under several brand names that vary from Viagra to Revatio and may also be found under its generic name. Commercially speaking Sildenafil citrate's, main competitor is tadalafil [Cialis] and vardenafil [Levitra]. While there maybe many medicines out there that are considered to be alternatives to Viagra, it is that has taken the world by storm and remains the top best seller.herbal viagra for women Viagra turns 10 this month, and didn't time just fly? It seems like only yesterday we started guffawing at the Symbolism for Dummies ads on TV for the little blue pill and its "erectile dysfunction" rivals -- footballs tossed through tires, faucets erupting. The spots ended with a list of potential side effects that sounded like a satire of potential side effects. "More than four hours?" we winced. "Ouch." However discomfiting the commercials, the Food and Drug Administration (FDA) approval of Viagra -- on March 27, 1998 -- is a landmark day in the history of sex. It seemed at the time like a biomedical revolution was upon us all, and about five minutes after word of the magical med went global, the question first was asked: Where is the women's version of Viagra? The short answer: They're still working on it. A bunch of companies have tried and failed to create "pink Viagra," as it's often called. Other companies have drugs in late stages of clinical testing, including a gel that recently began a make-or-break nationwide study with several thousand women. Give us five years, maybe less, say the most optimistic researchers and doctors. Though it's unclear exactly how many women would ask for a prescription, no one doubts that the first company that gets to market a remedy for female sexual dysfunction (FSD), as it's formally known, will earn a fortune. But as this race reaches what could be its final lap, not all of the spectators are cheering. Some, in fact, are booing as loudly as they can. A modest-size but fervent group of psychologists, academics and public health advocates contend that FSD isn't an authentic medical condition, or at least not the sort of problem that should be treated with drugs. These aren't the obtuse male physicians who for decades have been telling women distressed by their lack of libido that "it's all in your head." The anti-FSD crowd is mostly women, many of them self-described feminists. The most prominent is Leonore Tiefer, a psychotherapist and clinical associate professor at New York University, who has long decried what she calls "the medicalization of women's sexuality." "Drug companies want to say to women, 'You don't need to know anything; you can have the satisfying sex life that you seek -- people dancing on TV, the whole bit -- without knowing anything. Just ask your doctor,' " she says. "I resent that, because there are specific harms that come from being ignorant and dependent in the world we live in. There may be lots of people who aren't interested in sex, but is there a medical reason for that, and do we diagnose that?" best herbal viagra The most widely used remedy for erectile dysfunction; research has indicated that Viagra has an effect on the condition of the human heart as well as a male's penis. The hormonal stress normally exerted on the human heart has been noted to be decreased in men who take Viagra. When conducted with mice, the testing was more noticeable, Viagra having the tendency to avert harmful and long term effects of chronic hypertension on their heart. The study, lead by the John Hopkins research team, found that there is potential benefits for the treatment of pulmonary hypertension, linked in with how Viagra dilates genital blood vessels. Viagra works by dulling the heart beat, which is increased during stress. It works to decrease the force which is needed to pump blood from the heart to the rest of the body. The research conducted by David Kass, cardiologist and senior researcher of the John Hopkins study noticed Viagra can be effective in blocking short- term consequences of hormonal stresses in the heart. Further evidence on the testing of mice (although further research is needed until this is applicable to humans), indicated that negative effects of heart failure and cardiac hypertrophy on weakened heart muscles can be reversed. Further research is need in this area on humans however. Thirty five men and women were tested and injected with Dobutamine (a synthetic derivative of dopamine that increases heart rate and contractions), which resulted in increased rate of 150%. The men and women were then separated into two groups, one of which were given sildenafil (Viagra) and the other given a placebo (fake) pill. Results showed that the first group's heart rate decreased by 50%, whilst the latter group's further increased. This has led to widespread scientific interest in the effects of sildenafil (Viagra) on the human heart condition. buy viagra cialis levitra Sildenafil Tablets 25 mg, 50 mg, 100 mg (sil-DEN-a-fil) Treating erectile dysfunction (ED). It may also be used for other conditions as determined by your doctor. Viagra is a phosphodiesterase inhibitor. It works by helping to increase blood flow into the penis during sexual stimulation. This helps you to achieve and maintain an erection. you are taking nitrates (eg, isosorbide, nitroglycerin) in any form (eg, tablet, capsule, patch, ointment) or nitroprusside 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 Viagra . 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 a deformed penis (eg, Peyronie disease, cavernosal fibrosis), blood problems (eg, sickle cell anemia, leukemia, multiple myeloma), 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 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), or blood vessel 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 Viagra . 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 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 Viagra 's side effects This may not be a complete list of all interactions that may occur. Ask your health care provider if Viagra 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 Viagra as directed by your doctor. Check the label on the medicine for exact dosing instructions. An extra patient leaflet is available with Viagra . Talk to your pharmacist if you have questions about this information. Take Viagra by mouth with or without food. Viagra may not work as quickly if you take it with a high-fat meal. Viagra is usually taken about 1 hour before sexual activity. However, it may be taken anywhere from 4 hours to ? hour before sexual activity. Talk with your doctor about the best way to take Viagra . Do not take Viagra more often than once daily, or as directed by your doctor. If you miss a dose of Viagra and you still intend to engage in sexual activity, take it as soon as you remember. Continue to take it as directed by your doctor. Ask your health care provider any questions you may have about how to use Viagra . Viagra may cause dizziness, drowsiness, fainting, or blurred vision. These effects may be worse if you take it with alcohol or certain medicines. Use Viagra with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it. Viagra may cause dizziness, lightheadedness, or fainting; alcohol, hot weather, exercise, or fever may increase these effects. To prevent them, sit up or stand slowly, especially in the morning. Sit or lie down at the first sign of any of these effects. Patients with heart problems who take Viagra 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. Viagra 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. Do not use other medicines or treatments for erectile dysfunction while you are taking Viagra . Viagra does not stop the spread of HIV or other sexually transmitted diseases (STDs) to others through sexual contact. Use barrier methods of birth control (eg, condoms) if you have HIV infection or an STD. Viagra will not prevent pregnancy. If your partner may become pregnant and you wish to avoid pregnancy, be sure to use an effective form of birth control. Use Viagra with caution in the ELDERLY; they may be more sensitive to its effects. Viagra is not recommended for use in CHILDREN; safety and effectiveness in children have not been confirmed. PREGNANCY and BREAST-FEEDING: Viagra is not approved for use in women. If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Viagra while you are pregnant. It is not known if Viagra is found in breast milk. If you are or will be breast-feeding while you use Viagra , 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. Diarrhea; dizziness; flushing; headache; heartburn; mild, temporary vision changes (eg, blurred vision, sensitivity to light, blue/green color tint to vision); stuffy nose; upset stomach. Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); chest pain; fainting; fast or irregular heartbeat; painful or prolonged erection; ringing in the ears; seizure; severe or persistent dizziness; severe or persistent vision changes; 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 chest pain; fainting; prolonged erection; severe dizziness. Store Viagra 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 Viagra out of the reach of children and away from pets. If you have any questions about Viagra , please talk with your doctor, pharmacist, or other health care provider. Viagra 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 Viagra . 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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Erectile dysfunction in men is a common problem, even more so in men over the age of 45. different lifestyle traits can contribute to erectile dysfunction, however Viagra is the most commonly used cure for impotence and erectile dysfunction. It is not necessarily the case that men naturally experience a lower sexual drive or erectile dysfunction when they reach a certain age. A man's inability to gain and sustain an erection may be due more to abnormalities in treatable physical conditions. In 1983, Dr Giles Brindley made the discovery and demonstrated that a penis could be made erect by injecting it with the drug Phentolamine. He discovered the penis could be mad erect by relaxing the normally constricted blood vessels. Once the vessels are relaxed, they let increased blood into the penis, which then inflates to form an erection. Two problems however were soon recognised. Phentolamine is not selective enough to target only the penis to inflate and can unpredictably effect other parts of the body. Secondly, the erection is not brought on by sexual stimulation and a man will continue to have an erection until the drug wears off. Viagra combats such drawbacks however. It works by enhancing the natural process that occurs when a man is sexually stimulated. Viagra controls what we might call â€?softeners'- chemicals in the body designed to make the penis soften after an erection has occurred. When a man is sexually stimulated chemicals in the body relax the blood vessels in his penis and increase the blood flow. At the same time the body also produces phosphodiesterase (PDE5), which work to subside the erection afterwards. Erectile dysfunction is an imbalance which results in the inability of a male to sustain an erection. Viagra reduced such â€?softeners', allowing blood flow to the penis to create sustainable erections. Viagra does not take the place of stimulation but increases the effects of stimulation. After the Viagra has worn off (usually 4 or 5 hours later), the normal processes are restored to how they were prior to taking Viagra. Possible side effects can occur, such as flushing and dizziness, and if an individual experiences these, they should consult a doctor.  buy viagra now online 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! sildenafil side effects Viagra turns 10 this month, and didn't time just fly? It seems like only yesterday we started guffawing at the Symbolism for Dummies ads on TV for the little blue pill and its "erectile dysfunction" rivals -- footballs tossed through tires, faucets erupting. The spots ended with a list of potential side effects that sounded like a satire of potential side effects. "More than four hours?" we winced. "Ouch." However discomfiting the commercials, the Food and Drug Administration (FDA) approval of Viagra -- on March 27, 1998 -- is a landmark day in the history of sex. It seemed at the time like a biomedical revolution was upon us all, and about five minutes after word of the magical med went global, the question first was asked: Where is the women's version of Viagra? The short answer: They're still working on it. A bunch of companies have tried and failed to create "pink Viagra," as it's often called. Other companies have drugs in late stages of clinical testing, including a gel that recently began a make-or-break nationwide study with several thousand women. Give us five years, maybe less, say the most optimistic researchers and doctors. Though it's unclear exactly how many women would ask for a prescription, no one doubts that the first company that gets to market a remedy for female sexual dysfunction (FSD), as it's formally known, will earn a fortune. But as this race reaches what could be its final lap, not all of the spectators are cheering. Some, in fact, are booing as loudly as they can. A modest-size but fervent group of psychologists, academics and public health advocates contend that FSD isn't an authentic medical condition, or at least not the sort of problem that should be treated with drugs. These aren't the obtuse male physicians who for decades have been telling women distressed by their lack of libido that "it's all in your head." The anti-FSD crowd is mostly women, many of them self-described feminists. The most prominent is Leonore Tiefer, a psychotherapist and clinical associate professor at New York University, who has long decried what she calls "the medicalization of women's sexuality." "Drug companies want to say to women, 'You don't need to know anything; you can have the satisfying sex life that you seek -- people dancing on TV, the whole bit -- without knowing anything. Just ask your doctor,' " she says. "I resent that, because there are specific harms that come from being ignorant and dependent in the world we live in. There may be lots of people who aren't interested in sex, but is there a medical reason for that, and do we diagnose that?" citrato de sildenafil 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 plac