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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

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Viagra Professional is a new generation extra-strength prescription medicine that is taken orally for the treatment of erectile dysfunction only in men, powerfully activating the natural blood flow, followed by hardness and expansion of your sexually excited penis for peak sexual performance. Nowadays, erectile dysfunction can be safely and effectively treated. Oral Viagra Professional is one of the most refined and individualized forms of erectile dysfunction treatment. Carefully formulated and clinically tested, Viagra Professional will improve your sexual relationship with your partner in any case. Taking Viagra Professional about 15 minutes to 20 minutes before your sexual intercourse will help you get a most powerful erection ever, the desire will appear overwhelming, and you will feel rejuvenated. You will not need so much stimulation like before; just a touch will bathe you into the ocean of sexual fantasies popular herb contains sildenafil citrate Viagra has made a significant difference in the quality of life of millions of men and their partners. When the FDA approved the first oral medication for the treatment of erectile dysfunction in 1998, it gave rise to a new world of possibilities that would restore men to healthy sex routine. For plenty of these individuals, the ability to have reliable erections has brought them and their partners’ sexual satisfaction and a tremendous sense of emotional comfort in their lives. Many times, the return to sexual potency greatly enriches overall relationship satisfaction. Thanks to the advantages of Viagra, many men have come to the conclusion that they enjoy sex and had sex more frequently. While Viagra is not an aphrodisiac, men have reported an enhancement in sexual desire and arousal. Some are of the opinion that their orgasms felt more intense and enjoyable. Rather than being directly attached to Viagra, these sorts of opinions are most likely because of an increase in the man's general interest in sex, which is due to their Viagra-assisted reliable erections. Even with the sexual success that having a good erection allows, there are a wide array of psychological and relationship aspects involved in a couple's sexual routine. The continued quality of a couple's sexual routine will still be dependent on past, present and future relationship factors. To illustrate this point, consider The following factors: the sort of changes that occurred in the relationship when, thanks to Viagra, erectile problems were no longer a factor Some couples may enjoy renewed sexual routine, but others might feel that sex will now be required on demand. This can place unnecessary pressure on either partner to perform. If the erectile issues were due to problems between the partners, they need to be addressed. It is not unusual for men to be of the view that everything is in order once modern medicine has restored his erections. This is where work must be done to avoid future problems involving intimacy and communication about sex. Even with the restoration of a man's erections, the same sort of sexual turn-offs and difficulties surrounding sex, (timing, frequency, life-style, routines and methods) can still be crucial issues in judging overall sexual satisfaction. free online order viagra HE is only two, but Oliver Sherwood regularly takes Viagra - to keep him alive. The toddler has a rare condition that causes chronic high blood pressure. Something as simple a chest infection could kill him. The pulmonary hypertension, as it is known, can be controlled with four doses of Viagra a day. The drug improves blood flow, which in adults can boost erectile function but in rare cases such as Oliver's can open the veins and capillaries to aid circulation. His mother Sarah, a part-time nurse, said: "We joke when we pick up his drugs that it would be Christmas come early for most people. Obviously the dose isn't high enough to have the effect it would on adults. "Viagra is an expensive drug but it's actually one of the cheapest to treat pulmonary hypertension. "We're just hoping it'll continue to work as he grows a bit older." But Oliver's future could be in doubt because other drugs he could use as he gets older might no longer be funded by the Health Service. Pulmonary hypertension causes the blood pressure in the arteries in the lungs to rise, straining the heart and reducing blood oxygen levels, causing breathlessness and exhaustion. Symptoms include severe coughing and breathing problems as blood fills the lungs, constant nose bleeds, dizziness and chest pains. The condition, which affects 4,000 in Britain, often leads to heart failure. It is so rare that only five children a year are diagnosed with it in the UK. The survival rate is around five years, even with medication such as Oliver, who cannot walk more than a few steps without getting out of breath, takes one tablet of Sildenafil crushed into four 5ml doses a day. Doctors can increase the dose when his condition worsens, but there is no way of telling how much longer the drugs will be effective. As he grows up he will need to switch to more expensive treatments called Epoprostenol and Iloprost to control his condition. But the Government's drug rationing agency, the National Institute for Health and Clinical Excellence, is considering whether to continue prescribing them. Oliver's mother has started a petition calling for the Health Service to keep funding the treatments. Mrs Sherwood, 34, of Hucclecote, Gloucestershire, said: "The only hope we had was that he would be maintained through medication but if anything-happens in the future that hope may be taken away." The Pulmonary Hypertension Association said: "The clinical evidence for this is unfounded and it must be assumed it is based on cost alone." A spokesman for NICE added: "Our review of the evidence suggests that Sildenafil is both clinically effective and cost-effective in treating pulmonary arterial hypertension."

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Revatio, Viagra What is Viagra? Viagra relaxes muscles and increases blood flow to particular areas of the body. Sildenafil under the name Viagra is used to treat erectile dysfunction (impotence) in men. Another brand of sildenafil is Revatio, which is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women. Viagra may also be used for other purposes not listed in this medication guide. Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, and others), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket). Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking Viagra with a nitrate medicine can cause a serious decrease in blood pressure, leading to fainting, stroke, or heart attack. During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of Viagra. Do not take Viagra more than once a day. Allow 24 hours to pass between doses. Contact your doctor or seek emergency medical attention if your erection is painful or lasts longer than 4 hours. A prolonged erection (priapism) can damage the penis. Viagra can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking Viagra, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether Viagra is the actual cause of vision loss. Stop using Viagra and get emergency medical help if you have sudden vision loss. Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems. This includes nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, and others), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket). Nitrates are also found in some recreational drugs such as amyl nitrate or nitrite ("poppers"). Taking Viagra with a nitrate medicine can cause a serious decrease in blood pressure, leading to fainting, stroke, or heart attack. Before taking Viagra, tell your doctor if you are allergic to any drugs, or if you have: a recent history (in the past 6 months) of a heart attack, stroke, or heart rhythm disorder; a blood cell disorder such as sickle cell anemia, multiple myeloma, or leukemia; if you have been told you should not have sexual intercourse for health reasons. If you have any of these conditions, you may need a dose adjustment or special tests to safely take Viagra. Viagra can decrease blood flow to the optic nerve of the eye, causing sudden vision loss. This has occurred in a small number of people taking Viagra, most of whom also had heart disease, diabetes, high blood pressure, high cholesterol, or certain pre-existing eye problems, and in those who smoke or are over 50 years old. It is not clear whether Viagra is the actual cause of vision loss. Stop using Viagra and get emergency medical help if you have sudden vision loss. FDA pregnancy category B: This medication is not expected to be harmful to an unborn baby. Do not use Viagra without telling your doctor if you are pregnant or plan to become pregnant during treatment. It is not known if Viagra passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby. How should I take Viagra? Take Viagra exactly as it was prescribed for you. Do not take it in larger doses or for longer than recommended by your doctor. Follow the directions on your prescription label. Revatio is usually taken three times each day, about 4 to 6 hours apart. 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 Viagra more than once per day. 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. During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of Viagra. Store this medication at room temperature away from moisture and heat. What happens if I miss a dose? Viagra is used as needed, so you are not likely to be on a dosing schedule. If you miss a dose of Revatio, take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at the next regularly scheduled time. Do not take extra medicine to make up the missed dose. What happens if I overdose? Seek emergency medical attention if you think you have used too much of this medicine. Overdose symptoms may include chest pain, nausea, irregular heartbeat, and feeling light-headed or fainting. What should I avoid while taking Viagra? Avoid drinking alcohol, which can increase some of the side effects of Viagra. Avoid using other medicines to treat impotence, such as alprostadil (Caverject, Muse, Edex) or yohimbine (Yocon, Yodoxin, others), without first talking to your doctor. Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. During sexual activity, if you become dizzy or nauseated, or have pain, numbness, or tingling in your chest, arms, neck, or jaw, stop and call your doctor right away. You could be having a serious side effect of Viagra. ringing in your ears, or sudden hearing loss; chest pain or heavy feeling, pain spreading to the arm or shoulder, nausea, sweating, general ill feeling; swelling in your hands, ankles, or feet; feeling light-headed, fainting; or penis erection that is painful or lasts 4 hours or longer. warmth or redness in your face, neck, or chest; back pain. This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. What other drugs will affect Viagra? Do not take Viagra if you are also using a nitrate drug for chest pain or heart problems, including nitroglycerin (Nitrostat, Nitrolingual, Nitro-Dur, Nitro-Bid, Minitran, Deponit, Transderm-Nitro), isosorbide dinitrate (Dilatrate-SR, Isordil, Sorbitrate), and isosorbide mononitrate (Imdur, ISMO, Monoket), or recreational drugs such as amyl nitrate or nitrite ("poppers"). Before taking Viagra, tell your doctor about all other medications you use for erectile dysfunction, or if you are using any of the following medications: cimetidine (Tagamet, Tagamet HB); an antibiotic such as erythromycin (E-Mycin, Eryc, Ery-Tab) or clarithromycin (Biaxin); doxazosin (Cardura), prazosin (Minipress), Terazosin (Hytrin); HIV medicines such as amprenavir (Agenerase), tipranavir (Aptivus), darunavir (Prezista), efavirenz (Sustiva), nevirapine (Viramune), indinavir (Crixivan), saquinavir (Invirase, Fortovase), lopinavir/ritonavir (Kaletra), fosamprenavir (Lexiva), ritonavir (Norvir), atazanavir (Reyataz), or nelfinavir (Viracept); carbamazepine (Tegretol), phenobarbital (Luminal), or phenytoin (Dilantin); or rifampin (Rifadin, Rimactane) or rifabutin (Mycobutin). This list is not complete and there may be other drugs that can interact with Viagra. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor. Where can I get more information? Your pharmacist can provide more information about Viagra. What does my medication look like? Sildenafil is available with a prescription under the brand names Viagra and Revatio. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you. Revatio 20 mg - white, film-coated round tablets Viagra 25 mg - blue, film-coated tablets with a rounded-diamond shape Viagra 50 mg - blue, film-coated tablets with a rounded-diamond shape Viagra 100 mg - blue, film-coated tablets with a rounded-diamond shape Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed. Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

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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. 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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Viagra Professional is a new generation extra-strength prescription medicine that is taken orally for the treatment of erectile dysfunction only in men, powerfully activating the natural blood flow, followed by hardness and expansion of your sexually excited penis for peak sexual performance. Nowadays, erectile dysfunction can be safely and effectively treated. Oral Viagra Professional is one of the most refined and individualized forms of erectile dysfunction treatment. Carefully formulated and clinically tested, Viagra Professional will improve your sexual relationship with your partner in any case. Taking Viagra Professional about 15 minutes to 20 minutes before your sexual intercourse will help you get a most powerful erection ever, the desire will appear overwhelming, and you will feel rejuvenated. You will not need so much stimulation like before; just a touch will bathe you into the ocean of sexual fantasies

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.

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Drug Cialis for daily use. in 2003, and in 2007 alone they had a wopping figure of $798 million although this year it is expected to top over $1 billion in sales. They will report the official sale figures year-end January 29th. The once-a-day version will be marketed to men who anticipate having sex two or more times a week, without confining it to a limited time frame. When Cialis is taken daily, men can attempt sexual activity at any time. The low-dose daily version of the drug already is available in parts of Europe, Lilly said. Neither Viagra nor Levitra, a pair of competitors, is sold in once-daily doses. Althought Cialis maybe aggressively approaching the market with a new idea, was founded five years before Cialis company, and remains to be the most branded and popular erectile dysfunction drug in the World!  5 buy sildenafil citrate rxonline An oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5). Sildenafil citrate is designated chemically as 1 - [[3 - (6,7 - dihydro - 1 - methyl - 7 - oxo - 3 - propyl - 1H - pyrazolo[4,3 - d]pyrimidin - 5 - yl) - 4 - ethoxyphenyl]sulfonyl] - 4 - methylpiperazine citrate and has the following structural formula: Sildenafil citrate is a white to off-white crystalline powder with a solubility of 3.5 mg/mL in water and a molecular weight of 666.7. Viagra (sildenafil citrate) is formulated as blue, film-coated rounded-diamond-shaped tablets equivalent to 25 mg, 50 mg and 100 mg of sildenafil for oral administration. In addition to the active ingredient, sildenafil citrate, each tablet contains the following inactive ingredients: microcrystalline cellulose, anhydrous dibasic calcium phosphate, croscarmellose sodium, magnesium stearate, hypromellose, titanium dioxide, lactose, triacetin, and FD & C Blue #2 aluminum lake. The physiologic mechanism of erection of the penis involves release of nitric oxide (NO) in the corpus cavernosum during sexual stimulation. NO then activates the enzyme guanylate cyclase, which results in increased levels of cyclic guanosine monophosphate (cGMP), producing smooth muscle relaxation in the corpus cavernosum and allowing inflow of blood. Sildenafil has no direct relaxant effect on isolated human corpus cavernosum, but enhances the effect of nitric oxide (NO) by inhibiting phosphodiesterase type 5 (PDE5), which is responsible for degradation of cGMP in the corpus cavernosum. When sexual stimulation causes local release of NO, inhibition of PDE5 by sildenafil causes increased levels of cGMP in the corpus cavernosum, resulting in smooth muscle relaxation and inflow of blood to the corpus cavernosum. Sildenafil at recommended doses has no effect in the absence of sexual stimulation. Studies in vitro have shown that sildenafil is selective for PDE5. Its effect is more potent on PDE5 than on other known phosphodiesterases (10-fold for PDE6, >80-fold for PDE1, >700-fold for PDE2, PDE3, PDE4, PDE7, PDE8, PDE9, PDE10, and PDE11). The approximately 4,000-fold selectivity for PDE5 versus PDE3 is important because PDE3 is involved in control of cardiac contractility. Sildenafil is only about 10-fold as potent for PDE5 compared to PDE6, an enzyme found in the retina which is involved in the phototransduction pathway of the retina. This lower selectivity is thought to be the basis for abnormalities related to color vision observed with higher doses or plasma levels (see ). In addition to human corpus cavernosum smooth muscle, PDE5 is also found in lower concentrations in other tissues including platelets, vascular and visceral smooth muscle, and skeletal muscle. The inhibition of PDE5 in these tissues by sildenafil may be the basis for the enhanced platelet antiaggregatory activity of nitric oxide observed in vitro, an inhibition of platelet thrombus formation in vivo and peripheral arterial-venous dilatation in vivo. Viagra is rapidly absorbed after oral administration, with absolute bioavailability of about 40%. Its pharmacokinetics are dose-proportional over the recommended dose range. It is eliminated predominantly by hepatic metabolism (mainly cytochrome P450 3A4) and is converted to an active metabolite with properties similar to the parent, sildenafil. The concomitant use of potent cytochrome P450 3A4 inhibitors (e.g., erythromycin, ketoconazole, itraconazole) as well as the nonspecific CYP inhibitor, cimetidine, is associated with increased plasma levels of sildenafil (see ). Both sildenafil and the metabolite have terminal half lives of about 4 hours. in Healthy Male Volunteers. Viagra is rapidly absorbed. Maximum observed plasma concentrations are reached within 30 to 120 minutes (median 60 minutes) of oral dosing in the fasted state. When Viagra is taken with a high fat meal, the rate of absorption is reduced, with a mean delay in T of 29%. The mean steady state volume of distribution (Vss) for sildenafil is 105 L, indicating distribution into the tissues. Sildenafil and its major circulating N-desmethyl metabolite are both approximately 96% bound to plasma proteins. Protein binding is independent of total drug concentrations. Based upon measurements of sildenafil in semen of healthy volunteers 90 minutes after dosing, less than 0.001% of the administered dose may appear in the semen of patients. Sildenafil is cleared predominantly by the CYP3A4 (major route) and CYP2C9 (minor route) hepatic microsomal isoenzymes. The major circulating metabolite results from N-desmethylation of sildenafil, and is itself further metabolized. This metabolite has a PDE selectivity profile similar to sildenafil and an in vitro potency for PDE5 approximately 50% of the parent drug. Plasma concentrations of this metabolite are approximately 40% of those seen for sildenafil, so that the metabolite accounts for about 20% of sildenafil's pharmacologic effects. After either oral or intravenous administration, sildenafil is excreted as metabolites predominantly in the feces (approximately 80% of administered oral dose) and to a lesser extent in the urine (approximately 13% of the administered oral dose). Similar values for pharmacokinetic parameters were seen in normal volunteers and in the patient population, using a population pharmacokinetic approach. Healthy elderly volunteers (65 years or over) had a reduced clearance of sildenafil, with free plasma concentrations approximately 40% greater than those seen in healthy younger volunteers (18–45 years). In volunteers with mild (CLcr=50–80 mL/min) and moderate (CLcr=30–49 mL/min) renal impairment, the pharmacokinetics of a single oral dose of Viagra (50 mg) were not altered. In volunteers with severe (CLcr=<30 mL/min) renal impairment, sildenafil clearance was reduced, resulting in approximately doubling of AUC and C compared to age-matched volunteers with no renal impairment. In volunteers with hepatic cirrhosis (Child-Pugh A and B), sildenafil clearance was reduced, resulting in increases in AUC (84%) and C (47%) compared to age-matched volunteers with no hepatic impairment. Therefore, age >65, hepatic impairment and severe renal impairment are associated with increased plasma levels of sildenafil. A starting oral dose of 25 mg should be considered in those patients (see ). In eight double-blind, placebo-controlled crossover studies of patients with either organic or psychogenic erectile dysfunction, sexual stimulation resulted in improved erections, as assessed by an objective measurement of hardness and duration of erections (RigiScan ), after Viagra administration compared with placebo. Most studies assessed the efficacy of Viagra approximately 60 minutes post dose. The erectile response, as assessed by RigiScan , generally increased with increasing sildenafil dose and plasma concentration. The time course of effect was examined in one study, showing an effect for up to 4 hours but the response was diminished compared to 2 hours. Single oral doses of sildenafil (100 mg) administered to healthy volunteers produced decreases in supine blood pressure (mean maximum decrease in systolic/diastolic blood pressure of 8.4/5.5 mmHg). The decrease in blood pressure was most notable approximately 1–2 hours after dosing, and was not different than placebo at 8 hours. Similar effects on blood pressure were noted with 25 mg, 50 mg and 100 mg of Viagra, therefore the effects are not related to dose or plasma levels within this dosage range. Larger effects were recorded among patients receiving concomitant nitrates (see ). Systolic Blood Pressure, Healthy Volunteers. Single oral doses of sildenafil up to 100 mg produced no clinically relevant changes in the ECGs of normal male volunteers. Studies have produced relevant data on the effects of Viagra on cardiac output. In one small, open-label, uncontrolled, pilot study, eight patients with stable ischemic heart disease underwent Swan-Ganz catheterization. A total dose of 40 mg sildenafil was administered by four intravenous infusions. The results from this pilot study are shown in Table 1; the mean resting systolic and diastolic blood pressures decreased by 7% and 10% compared to baseline in these patients. Mean resting values for right atrial pressure, pulmonary artery pressure, pulmonary artery occluded pressure and cardiac output decreased by 28%, 28%, 20% and 7% respectively. Even though this total dosage produced plasma sildenafil concentrations which were approximately 2 to 5 times higher than the mean maximum plasma concentrations following a single oral dose of 100 mg in healthy male volunteers, the hemodynamic response to exercise was preserved in these patients. In a double-blind study, 144 patients with erectile dysfunction and chronic stable angina limited by exercise, not receiving chronic oral nitrates, were randomized to a single dose of placebo or Viagra 100 mg 1 hour prior to exercise testing. The primary endpoint was time to limiting angina in the evaluable cohort. The mean times (adjusted for baseline) to onset of limiting angina were 423.6 and 403.7 seconds for sildenafil (N=70) and placebo, respectively. These results demonstrated that the effect of Viagra on the primary endpoint was statistically non-inferior to placebo. At single oral doses of 100 mg and 200 mg, transient dose-related impairment of color discrimination (blue/green) was detected using the Farnsworth-Munsell 100-hue test, with peak effects near the time of peak plasma levels. This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. An evaluation of visual function at doses up to twice the maximum recommended dose revealed no effects of Viagra on visual acuity, intraocular pressure, or pupillometry. In clinical studies, Viagra was assessed for its effect on the ability of men with erectile dysfunction (ED) to engage in sexual activity and in many cases specifically on the ability to achieve and maintain an erection sufficient for satisfactory sexual activity. Viagra was evaluated primarily at doses of 25 mg, 50 mg and 100 mg in 21 randomized, double-blind, placebo-controlled trials of up to 6 months in duration, using a variety of study designs (fixed dose, titration, parallel, crossover). Viagra was administered to more than 3,000 patients aged 19 to 87 years, with ED of various etiologies (organic, psychogenic, mixed) with a mean duration of 5 years. Viagra demonstrated statistically significant improvement compared to placebo in all 21 studies. The studies that established benefit demonstrated improvements in success rates for sexual intercourse compared with placebo. The effectiveness of Viagra was evaluated in most studies using several assessment instruments. The primary measure in the principal studies was a sexual function questionnaire (the International Index of Erectile Function - IIEF) administered during a 4-week treatment-free run-in period, at baseline, at follow-up visits, and at the end of double-blind, placebo-controlled, at-home treatment. Two of the questions from the IIEF served as primary study endpoints; categorical responses were elicited to questions about (1) the ability to achieve erections sufficient for sexual intercourse and (2) the maintenance of erections after penetration. The patient addressed both questions at the final visit for the last 4 weeks of the study. The possible categorical responses to these questions were (0) no attempted intercourse, (1) never or almost never, (2) a few times, (3) sometimes, (4) most times, and (5) almost always or always. Also collected as part of the IIEF was information about other aspects of sexual function, including information on erectile function, orgasm, desire, satisfaction with intercourse, and overall sexual satisfaction. Sexual function data were also recorded by patients in a daily diary. In addition, patients were asked a global efficacy question and an optional partner questionnaire was administered. The effect on one of the major end points, maintenance of erections after penetration, is shown in Figure 3, for the pooled results of 5 fixed-dose, dose-response studies of greater than one month duration, showing response according to baseline function. Results with all doses have been pooled, but scores showed greater improvement at the 50 and 100 mg doses than at 25 mg. The pattern of responses was similar for the other principal question, the ability to achieve an erection sufficient for intercourse. The titration studies, in which most patients received 100 mg, showed similar results. Figure 3 shows that regardless of the baseline levels of function, subsequent function in patients treated with Viagra was better than that seen in patients treated with placebo. At the same time, on-treatment function was better in treated patients who were less impaired at baseline. Figure 3. Effect of Viagra and Placebo on Maintenance of Erection by Baseline Score. The frequency of patients reporting improvement of erections in response to a global question in four of the randomized, double-blind, parallel, placebo-controlled fixed dose studies (1797 patients) of 12 to 24 weeks duration is shown in Figure 4. These patients had erectile dysfunction at baseline that was characterized by median categorical scores of 2 (a few times) on principal IIEF questions. Erectile dysfunction was attributed to organic (58%; generally not characterized, but including diabetes and excluding spinal cord injury), psychogenic (17%), or mixed (24%) etiologies. Sixty-three percent, 74%, and 82% of the patients on 25 mg, 50 mg and 100 mg of Viagra, respectively, reported an improvement in their erections, compared to 24% on placebo. In the titration studies (n=644) (with most patients eventually receiving 100 mg), results were similar. Figure 4. Percentage of Patients Reporting an Improvement in Erections. The patients in studies had varying degrees of ED. One-third to one-half of the subjects in these studies reported successful intercourse at least once during a 4-week, treatment-free run-in period. In many of the studies, of both fixed dose and titration designs, daily diaries were kept by patients. In these studies, involving about 1600 patients, analyses of patient diaries showed no effect of Viagra on rates of attempted intercourse (about 2 per week), but there was clear treatment-related improvement in sexual function: per patient weekly success rates averaged 1.3 on 50–100 mg of Viagra vs 0.4 on placebo; similarly, group mean success rates (total successes divided by total attempts) were about 66% on Viagra vs about 20% on placebo. During 3 to 6 months of double-blind treatment or longer-term (1 year), open-label studies, few patients withdrew from active treatment for any reason, including lack of effectiveness. At the end of the long-term study, 88% of patients reported that Viagra improved their erections. Men with untreated ED had relatively low baseline scores for all aspects of sexual function measured (again using a 5-point scale) in the IIEF. Viagra improved these aspects of sexual function: frequency, firmness and maintenance of erections; frequency of orgasm; frequency and level of desire; frequency, satisfaction and enjoyment of intercourse; and overall relationship satisfaction. One randomized, double-blind, flexible-dose, placebo-controlled study included only patients with erectile dysfunction attributed to complications of diabetes mellitus (n=268). As in the other titration studies, patients were started on 50 mg and allowed to adjust the dose up to 100 mg or down to 25 mg of Viagra; all patients, however, were receiving 50 mg or 100 mg at the end of the study. There were highly statistically significant improvements on the two principal IIEF questions (frequency of successful penetration during sexual activity and maintenance of erections after penetration) on Viagra compared to placebo. On a global improvement question, 57% of Viagra patients reported improved erections versus 10% on placebo. Diary data indicated that on Viagra, 48% of intercourse attempts were successful versus 12% on placebo. One randomized, double-blind, placebo-controlled, crossover, flexible-dose (up to 100 mg) study of patients with erectile dysfunction resulting from spinal cord injury (n=178) was conducted. The changes from baseline in scoring on the two end point questions (frequency of successful penetration during sexual activity and maintenance of erections after penetration) were highly statistically significantly in favor of Viagra. On a global improvement question, 83% of patients reported improved erections on Viagra versus 12% on placebo. Diary data indicated that on Viagra, 59% of attempts at sexual intercourse were successful compared to 13% on placebo. Across all trials, Viagra improved the erections of 43% of radical prostatectomy patients compared to 15% on placebo. Subgroup analyses of responses to a global improvement question in patients with psychogenic etiology in two fixed-dose studies (total n=179) and two titration studies (total n=149) showed 84% of Viagra patients reported improvement in erections compared with 26% of placebo. The changes from baseline in scoring on the two end point questions (frequency of successful penetration during sexual activity and maintenance of erections after penetration) were highly statistically significantly in favor of Viagra. Diary data in two of the studies (n=178) showed rates of successful intercourse per attempt of 70% for Viagra and 29% for placebo. A review of population subgroups demonstrated efficacy regardless of baseline severity, etiology, race and age. Viagra was effective in a broad range of ED patients, including those with a history of coronary artery disease, hypertension, other cardiac disease, peripheral vascular disease, diabetes mellitus, depression, coronary artery bypass graft (CABG), radical prostatectomy, transurethral resection of the prostate (TURP) and spinal cord injury, and in patients taking antidepressants/antipsychotics and antihypertensives/diuretics. Analysis of the safety database showed no apparent difference in the side effect profile in patients taking Viagra with and without antihypertensive medication. This analysis was performed retrospectively, and was not powered to detect any pre-specified difference in adverse reactions. Viagra is indicated for the treatment of erectile dysfunction. ), Viagra was shown to potentiate the hypotensive effects of nitrates, and its administration to patients who are using organic nitrates, either regularly and/or intermittently, in any form is therefore contraindicated. After patients have taken Viagra, it is unknown when nitrates, if necessary, can be safely administered. Based on the pharmacokinetic profile of a single 100 mg oral dose given to healthy normal volunteers, the plasma levels of sildenafil at 24 hours post dose are approximately 2 ng/mL (compared to peak plasma levels of approximately 440 ng/mL) (see ). In the following patients: age >65, hepatic impairment (e.g., cirrhosis), severe renal impairment (e.g., creatinine clearance <30 mL/min), and concomitant use of potent cytochrome P450 3A4 inhibitors (erythromycin), plasma levels of sildenafil at 24 hours post dose have been found to be 3 to 8 times higher than those seen in healthy volunteers. Although plasma levels of sildenafil at 24 hours post dose are much lower than at peak concentration, it is unknown whether nitrates can be safely coadministered at this time point. Viagra is contraindicated in patients with a known hypersensitivity to any component of the tablet. There is a potential for cardiac risk of sexual activity in patients with preexisting cardiovascular disease. Therefore, treatments for erectile dysfunction, including Viagra, should not be generally used in men for whom sexual activity is inadvisable because of their underlying cardiovascular status. Viagra has systemic vasodilatory properties that resulted in transient decreases in supine blood pressure in healthy volunteers (mean maximum decrease of 8.4/5.5 mmHg), (see ). While this normally would be expected to be of little consequence in most patients, prior to prescribing Viagra, physicians should carefully consider whether their patients with underlying cardiovascular disease could be affected adversely by such vasodilatory effects, especially in combination with sexual activity. Patients with the following underlying conditions can be particularly sensitive to the actions of vasodilators including Viagra – those with left ventricular outflow obstruction (e.g. aortic stenosis, idiopathic hypertrophic subaortic stenosis) and those with severely impaired autonomic control of blood pressure. There is no controlled clinical data on the safety or efficacy of Viagra in the following groups; if prescribed, this should be done with caution. Patients who have suffered a myocardial infarction, stroke, or life-threatening arrhythmia within the last 6 months; Patients with retinitis pigmentosa (a minority of these patients have genetic disorders of retinal phosphodiesterases). Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of Viagra. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result. The concomitant administration of the protease inhibitor ritonavir substantially increases serum concentrations of sildenafil (11-fold increase in AUC). If Viagra is prescribed to patients taking ritonavir, caution should be used. Data from subjects exposed to high systemic levels of sildenafil are limited. Visual disturbances occurred more commonly at higher levels of sildenafil exposure. Decreased blood pressure, syncope, and prolonged erection were reported in some healthy volunteers exposed to high doses of sildenafil (200–800 mg). To decrease the chance of adverse events in patients taking ritonavir, a decrease in sildenafil dosage is recommended (see , ). The evaluation of erectile dysfunction should include a determination of potential underlying causes and the identification of appropriate treatment following a complete medical assessment. Before prescribing Viagra, it is important to note the following: Caution is advised when Phosphodiesterase Type 5 (PDE5) inhibitors are co-administered with alpha-blockers. PDE5 inhibitors, including Viagra, and alpha-adrenergic blocking agents are both vasodilators with blood pressure lowering effects. When vasodilators are used in combination, an additive effect on blood pressure may be anticipated. In some patients, concomitant use of these two drug classes can lower blood pressure significantly (see ) leading to symptomatic hypotension (e.g. dizziness, lightheadedness, fainting). Patients should be stable on alpha-blocker therapy prior to initiating a PDE5 inhibitor. Patients who demonstrate hemodynamic instability on alpha-blocker therapy alone are at increased risk of symptomatic hypotension with concomitant use of PDE5 inhibitors. In those patients who are stable on alpha-blocker therapy, PDE5 inhibitors should be initiated at the lowest dose. In those patients already taking an optimized dose of a PDE5 inhibitor, alpha-blocker therapy should be initiated at the lowest dose. Stepwise increase in alpha-blocker dose may be associated with further lowering of blood pressure when taking a PDE5 inhibitor. Safety of combined use of PDE5 inhibitors and alpha-blockers may be affected by other variables, including intravascular volume depletion and other anti-hypertensive drugs. Viagra has systemic vasodilatory properties and may augment the blood pressure lowering effect of other anti-hypertensive medications. Patients on multiple antihypertensive medications were included in the pivotal clinical trials for Viagra. In a separate drug interaction study, when amlodipine, 5 mg or 10 mg, and Viagra, 100 mg were orally administered concomitantly to hypertensive patients mean additional blood pressure reduction of 8 mmHg systolic and 7 mmHg diastolic were noted (see ). The safety of Viagra is unknown in patients with bleeding disorders and patients with active peptic ulceration. Viagra should be used with caution in patients with anatomical deformation of the penis (such as angulation, cavernosal fibrosis or Peyronie's disease), or in patients who have conditions which may predispose them to priapism (such as sickle cell anemia, multiple myeloma, or leukemia). The safety and efficacy of combinations of Viagra with other treatments for erectile dysfunction have not been studied. Therefore, the use of such combinations is not recommended. In humans, Viagra has no effect on bleeding time when taken alone or with aspirin. In vitro studies with human platelets indicate that sildenafil potentiates the antiaggregatory effect of sodium nitroprusside (a nitric oxide donor). The combination of heparin and Viagra had an additive effect on bleeding time in the anesthetized rabbit, but this interaction has not been studied in humans. Physicians should discuss with patients the contraindication of Viagra with regular and/or intermittent use of organic nitrates. Physicians should advise patients of the potential for Viagra to augment the blood pressure lowering effect of alpha-blockers and anti-hypertensive medications. Concomitant administration of Viagra and an alpha-blocker may lead to symptomatic hypotension in some patients. Therefore, when Viagra is co-administered with alpha-blockers, patients should be stable on alpha-blocker therapy prior to initiating Viagra treatment and Viagra should be initiated at the lowest dose. Physicians should discuss with patients the potential cardiac risk of sexual activity in patients with preexisting cardiovascular risk factors. Patients who experience symptoms (e.g., angina pectoris, dizziness, nausea) upon initiation of sexual activity should be advised to refrain from further activity and should discuss the episode with their physician. Physicians should advise patients to stop use of all PDE5 inhibitors, including Viagra, and seek medical attention in the event of a sudden loss of vision in one or both eyes. Such an event may be a sign of non-arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision, that has been reported rarely post-marketing in temporal association with the use of all PDE5 inhibitors. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors. Physicians should also discuss with patients the increased risk of NAION in individuals who have already experienced NAION in one eye, including whether such individuals could be adversely affected by use of vasodilators, such as PDE5 inhibitors (see ). Physicians should advise patients to stop taking PDE5 inhibitors, including Viagra, and seek prompt medical attention in the event of sudden decrease or loss of hearing. These events, which may be accompanied by tinnitus and dizziness, have been reported in temporal association to the intake of PDE5 inhibitors, including Viagra. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors or to other factors (see , ). Physicians should warn patients that prolonged erections greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported infrequently since market approval of Viagra. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency may result. The use of Viagra offers no protection against sexually transmitted diseases. Counseling of patients about the protective measures necessary to guard against sexually transmitted diseases, including the Human Immunodeficiency Virus (HIV), may be considered. Sildenafil metabolism is principally mediated by the cytochrome P450 (CYP) isoforms 3A4 (major route) and 2C9 (minor route). Therefore, inhibitors of these isoenzymes may reduce sildenafil clearance. Cimetidine (800 mg), a nonspecific CYP inhibitor, caused a 56% increase in plasma sildenafil concentrations when coadministered with Viagra (50 mg) to healthy volunteers. When a single 100 mg dose of Viagra was administered with erythromycin, a specific CYP3A4 inhibitor, at steady state (500 mg bid for 5 days), there was a 182% increase in sildenafil systemic exposure (AUC). In addition, in a study performed in healthy male volunteers, coadministration of the HIV protease inhibitor saquinavir, also a CYP3A4 inhibitor, at steady state (1200 mg tid) with Viagra (100 mg single dose) resulted in a 140% increase in sildenafil C and a 210% increase in sildenafil AUC. Viagra had no effect on saquinavir pharmacokinetics. Stronger CYP3A4 inhibitors such as ketoconazole or itraconazole would be expected to have still greater effects, and population data from patients in clinical trials did indicate a reduction in sildenafil clearance when it was coadministered with CYP3A4 inhibitors (such as ketoconazole, erythromycin, or cimetidine) (see ). In another study in healthy male volunteers, coadministration with the HIV protease inhibitor ritonavir, which is a highly potent P450 inhibitor, at steady state (500 mg bid) with Viagra (100 mg single dose) resulted in a 300% (4-fold) increase in sildenafil C and a 1000% (11-fold) increase in sildenafil plasma AUC. At 24 hours the plasma levels of sildenafil were still approximately 200 ng/mL, compared to approximately 5 ng/mL when sildenafil was dosed alone. This is consistent with ritonavir's marked effects on a broad range of P450 substrates. Viagra had no effect on ritonavir pharmacokinetics (see ). Although the interaction between other protease inhibitors and sildenafil has not been studied, their concomitant use is expected to increase sildenafil levels. In a study of healthy male volunteers, co-administration of sildenafil at steady state (80 mg t.i.d.) with endothelin receptor antagonist bosentan (a moderate inducer of CYP3A4, CYP2C9 and possibly of cytochrome P450 2C19) at steady state (125 mg b.i.d.) resulted in a 63% decrease of sildenafil AUC and a 55% decrease in sildenafil C . Concomitant administration of strong CYP3A4 inducers, such as rifampin, is expected to cause greater decreases in plasma levels of sildenafil. Single doses of antacid (magnesium hydroxide/aluminum hydroxide) did not affect the bioavailability of Viagra. Pharmacokinetic data from patients in clinical trials showed no effect on sildenafil pharmacokinetics of CYP2C9 inhibitors (such as tolbutamide, warfarin), CYP2D6 inhibitors (such as selective serotonin reuptake inhibitors, tricyclic antidepressants), thiazide and related diuretics, ACE inhibitors, and calcium channel blockers. The AUC of the active metabolite, N-desmethyl sildenafil, was increased 62% by loop and potassium-sparing diuretics and 102% by nonspecific beta-blockers. These effects on the metabolite are not expected to be of clinical consequence. Sildenafil is a weak inhibitor of the cytochrome P450 isoforms 1A2, 2C9, 2C19, 2D6, 2E1 and 3A4 (IC50 >150 µM). Given sildenafil peak plasma concentrations of approximately 1 µM after recommended doses, it is unlikely that Viagra will alter the clearance of substrates of these isoenzymes. Three double-blind, placebo-controlled, randomized, two-way crossover studies were conducted to assess the interaction of Viagra with doxazosin, an alpha-adrenergic blocking agent. In the first study, a single oral dose of Viagra 100 mg or matching placebo was administered in a 2-period crossover design to 4 generally healthy males with benign prostatic hyperplasia (BPH). Following at least 14 consecutive daily doses of doxazosin, Viagra 100 mg or matching placebo was administered simultaneously with doxazosin. Following a review of the data from these first 4 subjects (details provided below), the Viagra dose was reduced to 25 mg. Thereafter, 17 subjects were treated with Viagra 25 mg or matching placebo in combination with doxazosin 4 mg (15 subjects) or doxazosin 8mg (2 subjects). The mean subject age was 66.5 years. For the 17 subjects who received Viagra 25 mg and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows: Blood pressure was measured immediately pre-dose and at 15, 30, 45 minutes, and 1, 1.5, 2, 2.5, 3, 4, 6 and 8 hours after Viagra or matching placebo. Outliers were defined as subjects with a standing systolic blood pressure of <85 mmHg or a decrease from baseline in standing systolic blood pressure of >30 mmHg at one or more timepoints. There were no subjects treated with Viagra 25 mg who had a standing SBP < 85mmHg. There were three subjects with a decrease from baseline in standing systolic BP >30mmHg following Viagra 25 mg, one subject with a decrease from baseline in standing systolic BP > 30 mmHg following placebo and two subjects with a decrease from baseline in standing systolic BP > 30 mmHg following both Viagra and placebo. No severe adverse events potentially related to blood pressure effects were reported in this group. Of the four subjects who received Viagra 100 mg in the first part of this study, a severe adverse event related to blood pressure effect was reported in one patient (postural hypotension that began 35 minutes after dosing with Viagra with symptoms lasting for 8 hours), and mild adverse events potentially related to blood pressure effects were reported in two others (dizziness, headache and fatigue at 1 hour after dosing; and dizziness, lightheadedness and nausea at 4 hours after dosing). There were no reports of syncope among these patients. For these four subjects, the placebo-subtracted mean maximum decreases from baseline in supine and standing systolic blood pressures were 14.8 mmHg and 21.5 mmHg, respectively. Two of these subjects had a standing SBP < 85mmHg. Both of these subjects were protocol violators, one due to a low baseline standing SBP, and the other due to baseline orthostatic hypotension. In the second study, a single oral dose of Viagra 50 mg or matching placebo was administered in a 2-period crossover design to 20 generally healthy males with BPH. Following at least 14 consecutive days of doxazosin, Viagra 50mg or matching placebo was administered simultaneously with doxazosin 4 mg (17 subjects) or with doxazosin 8 mg (3 subjects). The mean subject age in this study was 63.9 years. Twenty subjects received Viagra 50 mg, but only 19 subjects received matching placebo. One patient discontinued the study prematurely due to an adverse event of hypotension following dosing with Viagra 50 mg. This patient had been taking minoxidil, a potent vasodilator, during the study. For the 19 subjects who received both Viagra and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows: Blood pressure was measured after administration of Viagra at the same times as those specified for the first doxazosin study. There were two subjects who had a standing SBP of < 85 mmHg. In these two subjects, hypotension was reported as a moderately severe adverse event, beginning at approximately 1 hour after administration of Viagra 50 mg and resolving after approximately 7.5 hours. There was one subject with a decrease from baseline in standing systolic BP >30mmHg following Viagra 50 mg and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both Viagra 50 mg and placebo. There were no severe adverse events potentially related to blood pressure and no episodes of syncope reported in this study. In the third study, a single oral dose of Viagra 100 mg or matching placebo was administered in a 3-period crossover design to 20 generally healthy males with BPH. In dose period 1, subjects were administered open-label doxazosin and a single dose of Viagra 50 mg simultaneously, after at least 14 consecutive days of doxazosin. If a subject did not successfully complete this first dosing period, he was discontinued from the study. Subjects who had successfully completed the previous doxazosin interaction study (using Viagra 50 mg), including no significant hemodynamic adverse events, were allowed to skip dose period 1. Treatment with doxazosin continued for at least 7 days after dose period 1. Thereafter, Viagra 100mg or matching placebo was administered simultaneously with doxazosin 4 mg (14 subjects) or doxazosin 8 mg (6 subjects) in standard crossover fashion. The mean subject age in this study was 66.4 years. Twenty-five subjects were screened. Two were discontinued after study period 1: one failed to meet pre-dose screening qualifications and the other experienced symptomatic hypotension as a moderately severe adverse event 30 minutes after dosing with open-label Viagra 50 mg. Of the twenty subjects who were ultimately assigned to treatment, a total of 13 subjects successfully completed dose period 1, and seven had successfully completed the previous doxazosin study (using Viagra 50 mg). For the 20 subjects who received Viagra 100 mg and matching placebo, the placebo-subtracted mean maximum decreases from baseline (95% CI) in systolic blood pressure were as follows: Blood pressure was measured after administration of Viagra at the same times as those specified for the previous doxazosin studies. There were three subjects who had a standing SBP of < 85 mmHg. All three were taking Viagra 100 mg, and all three reported mild adverse events at the time of reductions in standing SBP, including vasodilation and lightheadedness. There were four subjects with a decrease from baseline in standing systolic BP >30mmHg following Viagra 100 mg, one subject with a decrease from baseline in standing systolic BP > 30 mmHg following placebo and one subject with a decrease from baseline in standing systolic BP > 30 mmHg following both Viagra and placebo. While there were no severe adverse events potentially related to blood pressure reported in this study, one subject reported moderate vasodilatation after both Viagra 50 mg and 100 mg. There were no episodes of syncope reported in this study. When Viagra 100 mg oral was coadministered with amlodipine, 5 mg or 10 mg oral, to hypertensive patients, the mean additional reduction on supine blood pressure was 8 mmHg systolic and 7 mmHg diastolic. No significant interactions were shown with tolbutamide (250 mg) or warfarin (40 mg), both of which are metabolized by CYP2C9. Viagra (50 mg) did not potentiate the increase in bleeding time caused by aspirin (150 mg). Viagra (50 mg) did not potentiate the hypotensive effect of alcohol in healthy volunteers with mean maximum blood alcohol levels of 0.08%. In a study of healthy male volunteers, sildenafil (100 mg) did not affect the steady state pharmacokinetics of the HIV protease inhibitors, saquinavir and ritonavir, both of which are CYP3A4 substrates. Sildenafil at steady state (80 mg t.i.d.) resulted in a 50% increase in AUC and a 42% increase in C of bosentan (125 mg b.i.d.). Carcinogenesis, Mutagenesis, Impairment of Fertility Sildenafil was not carcinogenic when administered to rats for 24 months at a dose resulting in total systemic drug exposure (AUCs) for unbound sildenafil and its major metabolite of 29- and 42-times, for male and female rats, respectively, the exposures observed in human males given the Maximum Recommended Human Dose (MRHD) of 100 mg. Sildenafil was not carcinogenic when administered to mice for 18–21 months at dosages up to the Maximum Tolerated Dose (MTD) of 10 mg/kg/day, approximately 0.6 times the MRHD on a mg/m basis. Sildenafil was negative in in vitro bacterial and Chinese hamster ovary cell assays to detect mutagenicity, and in vitro human lymphocytes and in vivo mouse micronucleus assays to detect clastogenicity. There was no impairment of fertility in rats given sildenafil up to 60 mg/kg/day for 36 days to females and 102 days to males, a dose producing an AUC value of more than 25 times the human male AUC. There was no effect on sperm motility or morphology after single 100 mg oral doses of Viagra in healthy volunteers. Pregnancy, Nursing Mothers and Pediatric Use Viagra is not indicated for use in newborns, children, or women. No evidence of teratogenicity, embryotoxicity or fetotoxicity was observed in rats and rabbits which received up to 200 mg/kg/day during organogenesis. These doses represent, respectively, about 20 and 40 times the MRHD on a mg/m basis in a 50 kg subject. In the rat pre- and postnatal development study, the no observed adverse effect dose was 30 mg/kg/day given for 36 days. In the nonpregnant rat the AUC at this dose was about 20 times human AUC. There are no adequate and well-controlled studies of sildenafil in pregnant women. ). Since higher plasma levels may increase both the efficacy and incidence of adverse events, a starting dose of 25 mg should be considered (see ). Viagra was administered to over 3700 patients (aged 19–87 years) during pre-marketing clinical trials worldwide. Over 550 patients were treated for longer than one year. In placebo-controlled clinical studies, the discontinuation rate due to adverse events for Viagra (2.5%) was not significantly different from placebo (2.3%). The adverse events were generally transient and mild to moderate in nature. In trials of all designs, adverse events reported by patients receiving Viagra were generally similar. In fixed-dose studies, the incidence of some adverse events increased with dose. The nature of the adverse events in flexible-dose studies, which more closely reflect the recommended dosage regimen, was similar to that for fixed-dose studies. When Viagra was taken as recommended (on an as-needed basis) in flexible-dose, placebo-controlled clinical trials, the following adverse events were reported: Other adverse reactions occurred at a rate of >2%, but equally common on placebo: respiratory tract infection, back pain, flu syndrome, and arthralgia. In fixed-dose studies, dyspepsia (17%) and abnormal vision (11%) were more common at 100 mg than at lower doses. At doses above the recommended dose range, adverse events were similar to those detailed above but generally were reported more frequently. The following events occurred in <2% of patients in controlled clinical trials; a causal relationship to Viagra is uncertain. Reported events include those with a plausible relation to drug use; omitted are minor events and reports too imprecise to be meaningful: Body as a whole: face edema, photosensitivity reaction, shock, asthenia, pain, chills, accidental fall, abdominal pain, allergic reaction, chest pain, accidental injury. Cardiovascular: angina pectoris, AV block, migraine, syncope, tachycardia, palpitation, hypotension, postural hypotension, myocardial ischemia, cerebral thrombosis, cardiac arrest, heart failure, abnormal electrocardiogram, cardiomyopathy. Digestive: vomiting, glossitis, colitis, dysphagia, gastritis, gastroenteritis, esophagitis, stomatitis, dry mouth, liver function tests abnormal, rectal hemorrhage, gingivitis. Hemic and Lymphatic: anemia and leukopenia. Metabolic and Nutritional: thirst, edema, gout, unstable diabetes, hyperglycemia, peripheral edema, hyperuricemia, hypoglycemic reaction, hypernatremia. Musculoskeletal: arthritis, arthrosis, myalgia, tendon rupture, tenosynovitis, bone pain, myasthenia, synovitis. Nervous: ataxia, hypertonia, neuralgia, neuropathy, paresthesia, tremor, vertigo, depression, insomnia, somnolence, abnormal dreams, reflexes decreased, hypesthesia. Respiratory: asthma, dyspnea, laryngitis, pharyngitis, sinusitis, bronchitis, sputum increased, cough increased. Skin and Appendages: urticaria, herpes simplex, pruritus, sweating, skin ulcer, contact dermatitis, exfoliative dermatitis. Special Senses: sudden decrease or loss of hearing, mydriasis, conjunctivitis, photophobia, tinnitus, eye pain, ear pain, eye hemorrhage, cataract, dry eyes. Urogenital: cystitis, nocturia, urinary frequency, breast enlargement, urinary incontinence, abnormal ejaculation, genital edema and anorgasmia. Serious cardiovascular, cerebrovascular, and vascular events, including myocardial infarction, sudden cardiac death, ventricular arrhythmia, cerebrovascular hemorrhage, transient ischemic attack, hypertension, subarachnoid and intracerebral hemorrhages, and pulmonary hemorrhage have been reported post-marketing in temporal association with the use of Viagra. Most, but not all, of these patients had preexisting cardiovascular risk factors. Many of these events were reported to occur during or shortly after sexual activity, and a few were reported to occur shortly after the use of Viagra without sexual activity. Others were reported to have occurred hours to days after the use of Viagra and sexual activity. It is not possible to determine whether these events are related directly to Viagra, to sexual activity, to the patient's underlying cardiovascular disease, to a combination of these factors, or to other factors (see for further important cardiovascular information). Cases of sudden decrease or loss of hearing have been reported postmarketing in temporal association with the use of PDE5 inhibitors, including Viagra. In some of the cases, medical conditions and other factors were reported that may have also played a role in the otologic adverse events. In many cases, medical follow-up information was limited. It is not possible to determine whether these reported events are related directly to the use of Viagra, to the patient’s underlying risk factors for hearing loss, a combination of these factors, or to other factors (see ). Nervous: seizure and anxiety. Urogenital: prolonged erection, priapism (see ), and hematuria. Special Senses: diplopia, temporary vision loss/decreased vision, ocular redness or bloodshot appearance, ocular burning, ocular swelling/pressure, increased intraocular pressure, retinal vascular disease or bleeding, vitreous detachment/traction, paramacular edema and epistaxis. Non-arteritic anterior ischemic optic neuropathy (NAION), a cause of decreased vision including permanent loss of vision, has been reported rarely post-marketing in temporal association with the use of phosphodiesterase type 5 (PDE5) inhibitors, including Viagra. Most, but not all, of these patients had underlying anatomic or vascular risk factors for developing NAION, including but not necessarily limited to: low cup to disc ratio ("crowded disc"), age over 50, diabetes, hypertension, coronary artery disease, hyperlipidemia and smoking. It is not possible to determine whether these events are related directly to the use of PDE5 inhibitors, to the patient's underlying vascular risk factors or anatomical defects, to a combination of these factors, or to other factors (see ). In studies with healthy volunteers of single doses up to 800 mg, adverse events were similar to those seen at lower doses but incidence rates were increased. In cases of overdose, standard supportive measures should be adopted as required. Renal dialysis is not expected to accelerate clearance as sildenafil is highly bound to plasma proteins and it is not eliminated in the urine. For most patients, the recommended dose is 50 mg taken, as needed, approximately 1 hour before sexual activity. However, Viagra may be taken anywhere from 4 hours to 0.5 hour before sexual activity. Based on effectiveness and toleration, the dose may be increased to a maximum recommended dose of 100 mg or decreased to 25 mg. The maximum recommended dosing frequency is once per day. The following factors are associated with increased plasma levels of sildenafil: age >65 (40% increase in AUC), hepatic impairment (e.g., cirrhosis, 80%), severe renal impairment (creatinine clearance <30 mL/min, 100%), and concomitant use of potent cytochrome P450 3A4 inhibitors [ketoconazole, itraconazole, erythromycin (182%), saquinavir (210%)]. Since higher plasma levels may increase both the efficacy and incidence of adverse events, a starting dose of 25 mg should be considered in these patients. Ritonavir greatly increased the systemic level of sildenafil in a study of healthy, non-HIV infected volunteers (11-fold increase in AUC, see .) Based on these pharmacokinetic data, it is recommended not to exceed a maximum single dose of 25 mg of Viagra in a 48 hour period. Viagra was shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors or nitrates in any form is therefore contraindicated. When Viagra is co-administered with an alpha-blocker, patients should be stable on alpha-blocker therapy prior to initiating Viagra treatment and Viagra should be initiated at the lowest dose (see ). Viagra (sildenafil citrate) is supplied as blue, film-coated, rounded-diamond-shaped tablets containing sildenafil citrate equivalent to the nominally indicated amount of sildenafil as follows: Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F) [see USP Controlled Room Temperature]. LAB-0221-8.0 ®. It is not meant to take the place of your doctor's instructions. Read this information carefully before you start taking Viagra. Ask your doctor or pharmacist if you do not understand any of this information or if you want to know more about Viagra. This medicine can help many men when it is used as prescribed by their doctors. However, Viagra is not for everyone. It is intended for use only by men who have a condition called erectile dysfunction. Viagra must never be used by men who are taking medicines that contain nitrates of any kind, at any time. This includes nitroglycerin. If you take Viagra with any nitrate medicine your blood pressure could suddenly drop to an unsafe or life threatening level. • WHAT IS Viagra? Viagra is a pill used to treat erectile dysfunction (impotence) in men. It can help many men who have erectile dysfunction get and keep an erection when they become sexually excited (stimulated). You will not get an erection just by taking this medicine. Viagra helps a man with erectile dysfunction get an erection only when he is sexually excited. When a man is sexually excited, the penis rapidly fills with more blood than usual. The penis then expands and hardens. This is called an erection. After the man is done having sex, this extra blood flows out of the penis back into the body. The erection goes away. If an erection lasts for a long time (more than 6 hours), it can permanently damage your penis. You should call a doctor immediately if you ever have a prolonged erection that lasts more than 4 hours. Some conditions and medicines interfere with this natural erection process. The penis cannot fill with enough blood. The man cannot have an erection. This is called erectile dysfunction if it becomes a frequent problem. During sex, your heart works harder. Therefore sexual activity may not be advisable for people who have heart problems. Before you start any treatment for erectile dysfunction, ask your doctor if your heart is healthy enough to handle the extra strain of having sex. If you have chest pains, dizziness or nausea during sex, stop having sex and immediately tell your doctor you have had this problem. Viagra enables many men with erectile dysfunction to respond to sexual stimulation. When a man is sexually excited, Viagra helps the penis fill with enough blood to cause an erection. After sex is over, the erection goes away. As noted above (How Sex Affects the Body), ask your doctor if your heart is healthy enough for sexual activity. If you take any medicines that contain nitrates – either regularly or as needed – you should never take Viagra. If you take Viagra with any nitrate medicine or recreational drug containing nitrates, your blood pressure could suddenly drop to an unsafe level. You could get dizzy, faint, or even have a heart attack or stroke. Nitrates are found in many prescription medicines that are used to treat angina (chest pain due to heart disease) such as: nitroglycerin (sprays, ointments, skin patches or pastes, and tablets that are swallowed or dissolved in the mouth) isosorbide mononitrate and isosorbide dinitrate (tablets that are swallowed, chewed, or dissolved in the mouth) Nitrates are also found in recreational drugs such as amyl nitrate or nitrite ("poppers"). If you are not sure if any of your medicines contain nitrates, or if you do not understand what nitrates are, ask your doctor or pharmacist. Viagra is only for patients with erectile dysfunction. Viagra is not for newborns, children, or women. Do not let anyone else take your Viagra. Viagra must be used only under a doctor's supervision. Viagra does not cure erectile dysfunction. It is a treatment for erectile dysfunction. Viagra does not protect you or your partner from getting sexually transmitted diseases, including HIV—the virus that causes AIDS. Viagra is not a hormone or an aphrodisiac. Only your doctor can decide if Viagra is right for you. Viagra can cause mild, temporary lowering of your blood pressure. You will need to have a thorough medical exam to diagnose your erectile dysfunction and to find out if you can safely take Viagra alone or with your other medicines. Your doctor should determine if your heart is healthy enough to handle the extra strain of having sex. have ever had any heart problems (e.g., angina, chest pain, heart failure, irregular heart beats, heart attack or narrowing of the aortic valve) have ever had any blood problems, including sickle cell anemia or leukemia have a deformed penis, Peyronie's disease, or ever had an erection that lasted more than 4 hours Some medicines can change the way Viagra works. Tell your doctor about any medicines you are taking. Do not start or stop taking any medicines before checking with your doctor or pharmacist. This includes prescription and nonprescription medicines or remedies: Remember, Viagra should never be used with medicines that contain nitrates (see Viagra Is Not for Everyone). If you are taking medicines called alpha-blockers for the treatment of high blood pressure or prostate problems, your blood pressure could suddenly drop. You could get dizzy or faint. If you are taking a protease inhibitor, your dose may be adjusted (please see Finding the Right Dose for You). Viagra should not be used with any other medical treatments that cause erections. These treatments include pills, medicines that are injected or inserted into the penis, implants or vacuum pumps. Viagra comes in different doses (25 mg, 50 mg and 100 mg). If you do not get the results you expect, talk with your doctor. You and your doctor can determine the dose that works best for you. Do not take more Viagra than your doctor prescribes. If you think you need a larger dose of Viagra, check with your doctor. Viagra should not be taken more than once a day. Your doctor may prescribe a lower dose of Viagra in certain circumstances. For example: If you are older than age 65, or have serious liver or kidney problems, your doctor may start you at the lowest dose (25 mg) of Viagra. If you are taking protease inhibitors, such as for the treatment of HIV, your doctor may recommend a 25 mg dose and may limit you to a maximum single dose of 25 mg of Viagra in a 48 hour period. If you have prostate problems or high blood pressure for which you take medicines called alpha blockers, your doctor may start you on a lower dose of Viagra. Take Viagra about one hour before you plan to have sex. Beginning in about 30 minutes and for up to 4 hours, Viagra can help you get an erection if you are sexually excited. If you take Viagra after a high-fat meal (such as a cheeseburger and french fries), the medicine may take a little longer to start working. Viagra can help you get an erection when you are sexually excited. You will not get an erection just by taking the pill. Like all medicines, Viagra can cause some side effects. These effects are usually mild to moderate and usually don't last longer than a few hours. Some of these side effects are more likely to occur with higher doses. The most common side effects of Viagra are headache, flushing of the face, and upset stomach. Less common side effects that may occur are temporary changes in color vision (such as trouble telling the difference between blue and green objects or having a blue color tinge to them), eyes being more sensitive to light, or blurred vision. In rare instances, men taking PDE5 inhibitors (oral erectile dysfunction medicines, including Viagra) reported a sudden decrease or loss of vision in one or both eyes. It is not possible to determine whether these events are related directly to these medicines, to other factors such as high blood pressure or diabetes, or to a combination of these. If you experience sudden decrease or loss of vision, stop taking PDE5 inhibitors, including Viagra, and call a doctor right away. In rare instances, men have reported an erection that lasts many hours. You should call a doctor immediately if you ever have an erection that lasts more than 4 hours. If not treated right away, permanent damage to your penis could occur (see How Sex Affects the Body). Sudden loss or decrease in hearing, sometimes with ringing in the ears and dizziness, has been rarely reported in people taking PDE5 inhibitors, including Viagra. It is not possible to determine whether these events are related directly to the PDE5 inhibitors, to other diseases or medications, to other factors, or to a combination of factors. If you experience these symptoms, stop taking Viagra and contact a doctor right away. Heart attack, stroke, irregular heart beats, and death have been reported rarely in men taking Viagra. Most, but not all, of these men had heart problems before taking this medicine. It is not possible to determine whether these events were directly related to Viagra. Viagra may cause other side effects besides those listed on this sheet. If you want more information or develop any side effects or symptoms you are concerned about, call your doctor. In case of accidental overdose, call your doctor right away. Keep Viagra out of the reach of children. Keep Viagra in its original container. Store at 25°C (77°F); excursions permitted to 15–30°C (59–86°F) [see USP Controlled Room Temperature]. Viagra is a prescription medicine used to treat erectile dysfunction. Only your doctor can decide if it is right for you. This sheet is only a summary. If you have any questions or want more information about Viagra, talk with your doctor or pharmacist, visit www.Viagra.com, or call 1-888-4Viagra. LAB-0220-6.0 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?"  connecticut generic meltabs viagra 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. 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. How should I take Viagra? Your healthcare provider may prescribe Viagra as one tablet once a day, about 1 hour before sexual activity. However, Viagra may be taken anywhere from 30 minutes to 4 hours before sexual activity. What are some possible side effects of Viagra? a complete list of side effects reported with Viagra. Your healthcare provider can discuss with you a more complete list of side effects. Viagra is generally well tolerated. If any side effects are experienced, they are usually mild and temporary. 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 on Viagra, ask your healthcare provider. More Articles... If you have any questions or comments on senior health nutrition, fitness, etc., go to the is for educational / reference use only. 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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Viagra is giving older men a new sex life, but many wives are upset about it. according to a $600,000 study paid for by the health research council of new zealand, plenty of women are blaming health care providers for giving their husbands viagra without considering its effects on them. these women believe men's clinics use viagra as a quick fix for men instead of assisting couples with other issues in their relationship or just accepting that older people do not require sex as often as younger people. the study was conducted on the basis of direct interviews with 27 women with an average age of 53, and 33 men who were interested in being a part of the study. officially, more than 15 million people around the world have taken viagra since its inception in 1998. despite being a costly affair, people are still fond of this drug. viagra’s price is $100 for a packet of four pills; each pill can have an effect for up to 12 hours. about a quarter of the women came forward for the research because they were interested in discussing about the detrimental effects of viagra. the other three quarters of the women came into the study because they were not feeling at ease with all the sex they were compelled to perform after their husbands opted for viagra. women told the researchers that they feel unnecessary pressure to have sex at night as well as the next morning so the husband could double their pleasure. a few older women experienced pain during sex due to post menopausal vaginal dryness even when they were using lubricants during sex. the irony is that most of the health providers just treat this as a men’s problem rather than a couple’s problem. it is mandatory that how woman feels should be taken into account. doctors are of the opinion that when male patients asked for prescription of viagra, they cannot force them to talk to their partners first. according to doctors, interaction between the partners is extremely crucial in this matter but, though they encourage it among male patients, to implement it rests solely in the hands of male patients. interestingly, those women who are not interested in having sex more frequently risked being labelled dysfunctional themselves causing some pressure on them to have some medical evaluation. 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 .

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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. citrate find get sildenafil way 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. zenegra print sildenafil citrate order form Drugs for treating Erectile Dysfunction (ED) can be taken orally, injected directly into the penis or inserted into the urethra at the tip of the penis. Viagra was the first pill to treat ED when the Food and Drug Administration (FDA) approved it in 1998. Later, vardenafil hydrochloride (Levitra) and tadalafil (Cialis) were given the green light by the FDA to treat ED. Many other oral medicines are being tested for safety and effectiveness. Viagra, Levitra and Cialis belong to a class of drugs known as phosphodiesterase (PDE) inhibitors. The medication is generally taken an hour before any intended sex act, these drugs work by increasing the effects of nitric oxide. Nitric oxide is a chemical whose main function is to relax the smooth muscles in the penis during sexual stimulation and allow increased blood flow. While there is no doubt that oral medicines improve the response to sexual stimulation, they do not trigger an automatic erection (as injections do). The advisable dose for Viagra is about 50 mg, though the physician may adjust this dose to a range of 25 to 100 mg depending on the patient. The advisable dose for Levitra or Cialis is about 10 mg, which can be increased to 20 mg if 10 mg turns out to be insufficient. A decreased dose of 5 mg (or as low as 2.25 mg) is available on the market for patients who take other medicines or have diseases that may decrease in the body's ability to use the drug. No PDE inhibitors should be used more than once a day. It is mandatory that men who take nitrate-based drugs, such as nitro-glycerine for heart issues, should not use either drug because the combination can lead to a sudden decrease in blood pressure. In addition, it is recommended that you tell your doctor if you take any drugs known as alpha-blockers. These are mainly used to treat prostate enlargement or high blood pressure. Often, oral testosterone can minimize ED in men with low levels of natural testosterone, but it is often ineffective and may lead to liver damage. Many patients are of the opinion that other oral drugs (namely yohimbine hydrochloride, dopamine, serotonin agonists, and trazodone) are pretty effective, but the results of scientific research studies have been inconsistent to say the least. Improvements may be instances of the placebo effect, a change that results from the patient's belief that an improvement will take place..
Looking at the psychology of impotence is comparable to taking a trip down the amazon during the rainy season. it is a topic fraught with hidden currents, treacherous shallows and wide meanderings. viagra, the little blue pill has given a new life to the treatment of impotence and has a significant bearing on men who are suffering from erectile dysfunction. it is worth noting that just finding a "quick fix" for impotence does not overcome other issues that may have been the cause of the dysfunction before treatment began. overcoming impotence often gives men unrealistic expectations about their ability to instantly come over their emotional as well as physical problems. for most men, their ability to get an erection and have sex is considered as a important part of their masculinity and potency. it is no surprise that the onset of impotence, even when due to underlying physical condition, can lead to psychological issues that increase the problem of impotence. generally speaking, performance anxiety is a very real problem for many men. in other words, the fear of not being able to perform, dissatisfaction with penis size and self-consciousness about body appearance can all lead to the thing that most men do not want even in their dreams: failure to get an erection. most men have an occasional episode of impotence due to anxiety. if erectile dysfunction has been there for considerable amount of time, this anxiety is multiplied. from a physiological point of view, anxiety can effectively prevent a man from becoming aroused and maintaining an erection. all the psychological issues seem to disappear with the help of viagra, which is why it is the most effective and most prescribed erectile dysfunction treatment on the market. there is no reason to feel awkward if you are having issues getting an erection. just remember that erectile dysfunction is a common problem and can happen to anyone of any age. when you take viagra for the first time it provides harder erections and plays a prominent role in maintaining the erection for a longer period of time during sex. as viagra has been proven safe to use in men who are suffering from heart problems, high cholesterol, diabetes, high blood pressure, prostate problems as well as spinal injury you feel at ease when using it. the best part about viagra is that it works when you want it to. studies have shown that it works for most men in as little as fourteen minutes, on average within half an hour, and makes it’s presence felt for at least four hours. 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.

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Impotence and erectile dysfunction affect many men, and in recent years, have become more widely discussed. Various treatments have been developed to cure such problems, the most popular and widely available being Viagra. There are more and more alternatives to Viagra appearing on the market, some of which are more reliable and trustworthy than others! Read on to discover a legitimate and safe alternatives to Viagra. Firstly, some men experience side effects from using Viagra. Although this isn't widespread amongst users, Viagra alternatives don't involve any risk of side effects. Side effects such as dizziness, loss of vision, headaches, flushing and low blood pressure can occur. In more extreme cases some men have experienced priapism( a painful condition when a man's penis fails to return to its natural flaccid state. The Viagra alternative extracts such side effects as the non- chemical remedies consist of natural herbal ingredients. Such alternatives are widely available and their increased use by male consumers on the rise. Secondly, such herbal alternatives are available over the counter or on the internet (as are Viagra however), without a prescription, and are relatively cheap, ranging from $1- 1.50 a pill. Generic Viagra treatments however are also available without a prescription, and although are slightly more expensive they still appear to be the most popular choice amongst consumers. Thirdly, an alternative Viagra treatment takes 30- 45 minutes to work, however the length of its effect varies widely. Certain herbal ingredients work effectively such as Epicedium (commonly known as the horny goat weed), which is a great sex drive booster. Viagra however, whilst taking about the same time to have an effect on a man's penis normally lasts for around 1-2 hours (sometimes more) from the time of ingestion, and so guarantees a man sexual pleasure. It is important for each individual male to weigh up the pro's and cons to his preferred treatment of erectile dysfunction, taking into account all the available information. viagra generic 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.cheapest viagra in uk

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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 medicin