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Erectile Dysfunction (Impotence) »
Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain an erection for satisfactory sexual activity. Erectile dysfunction is different from other conditions that interfere with male sexual intercourse, such as lack of sexual desire (decreased libido) and problems with ejaculation and orgasm (ejaculatory dysfunction). This article focuses on the evaluation and treatment of erectile dysfunction.
Erectile dysfunction (ED, impotence) varies in severity; some men have a total inability to achieve an erection, others have an inconsistent ability to achieve an erection, and still others can sustain only brief erections. The variations in severity of erectile dysfunction make estimating its frequency difficult. Many men also are reluctant to discuss erectile dysfunction with their doctors due to embarrassment, and thus the condition is unde...
VIAGRA®
(sildenafil citrate) Tablets
VIAGRA® (sildenafil citrate) , an oral therapy for erectile dysfunction, is the citrate salt of sildenafil, a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE5).
Sildenafil citrate is designated chemically as 1-[[3-(6,7-dihydro-1-methyl-7-oxo-3-propyl-1H pyrazolo[4,3-d]pyrimidin-5-yl)-4-ethoxyphenyl]sulfonyl]-4-methylpiperazine citrate and has the following structural formula:
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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.
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 sildenafil.
Stop using sildenafil and call your doctor at once if you have any of these serious side effects:
Read All Potential Side Effects and See Pictures of Viagra »
Before taking sildenafil, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: sickle cell disease, high or low blood pressure, a severe loss of body water (dehydration), history of painful/prolonged erection (priapism), eye problems (such as decreased vision in one or both eyes, retinitis pigmentosa), heart problems (such as heart attack or irregular heartbeat in the past 6 months, heart failure, chest pain/angina, aortic stenosis, idiopathic hypertrophic subaortic stenosis), kidney disease, liver...
Last reviewed on RxList: 1/3/2011
This monograph has been modified to include the generic and brand name in many instances.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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