· Description and Brand Names. Drug information provided by: Merative, Micromedex® US Brand Name. Revatio; Viagra; Descriptions. Sildenafil is used to treat .Viagra doesn’t work instantaneously. This finding is consistent with the inhibition of PDE6, which is involved in phototransduction in the retina. Sildenafil may not be safe to take for people with certain medical conditions including: a past history of stroke or heart attack in the last 6 months retinitis pigmentosa an eye disease It can also interact with many other medicines, particularly nitrates used in heart disease , amyl nitrite and blood pressure medicines. Based upon measurements of sildenafil in semen of healthy volunteers 90 minutes after dosing, less than 0. Emling S.Dosage. The dose of Cialis you need will depend on whether you’re taking it daily or as needed. Daily doses are often between and 5 milligrams (mg). The as-needed dose is usually 10 mg but can range from 5–20 mg. The typicaldose of Viagra is 50 mg. However, the dosage can range from 25– mg. Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. Sildenafil (Liqrev, Revatio) is used to improve the ability to exercise in adults (Liqrev, Revatio) and children 1 year of age and older (Revatio) with pulmonary arterial hypertension (PAH; high blood pressure in the vessels carrying blood to the . AdGet a Prescription for ED treatment, discreetly deliverED to your ive Offers · How It Works · Get More InfoService Catalog: Instagram, P.E. Treatments, GET MORE INFO, Terms & Conditions and more.Magnotti will be happy to go over your list in a meeting. Maximum observed plasma concentrations are reached within 30 to minutes median 60 minutes of oral dosing in the fasted state. About sildenafil Viagra Sildenafil is a medicine used to treat erection problems erectile dysfunction. Human Reproduction. If you have an erection that lasts for more than 4 hours, you should go to the nearest hospital emergency department.