The 100 mg Viagra tablet is taken as needed, not more than once a day

The maximum recommended dose of sildenafil is 100 mg. The maximum recommended dosing frequency is once per day. For most patients the recommended dose is 50 mg taken as needed, approximately 1 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. Adults 65 years of age and older may use 25 mg as a single dose no more than once a day. VIAGRA tablets contain sildenafil citrate equivalent to 25 mg, 50 mg, or 100 mg of sildenafil. VIAGRA is supplied as blue, film-coated, rounded-diamond-shaped tablets. Viagra is indicated for erectile dysfunction. Sexual stimulation is required. Store at 25 C (77 F); excursions permitted to 15 to 30 C (59 to 86 F).

VIAGRA may be taken anywhere from 30 minutes to 4 hours before sexual activity. Most studies assessed the efficacy of VIAGRA approximately 60 minutes post dose. For most patients the recommended time is approximately 1 hour before sexual activity. Both sildenafil and the metabolite have terminal half lives of about 4 hours. The pharmacokinetics of sildenafil are dose-proportional over the recommended dose range. There was no effect on sperm motility or morphology after single 100 mg oral doses of VIAGRA in healthy volunteers. 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.

A high-fat meal can delay how fast sildenafil works. 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 Tmax of 60 minutes. Sildenafil may be taken with or without food. The 100 mg tablet is one of the three labelled film-coated strengths. See the meal-timing note.

VIAGRA is not indicated for use in females. VIAGRA is not indicated for use in pediatric patients. Safety and effectiveness have not been established in pediatric patients. There are no data with the use of VIAGRA in pregnant women to inform any drug-associated risks for adverse developmental outcomes. Animal reproduction studies conducted with sildenafil did not show adverse developmental outcomes when administered during organogenesis in rats and rabbits at oral doses up to 16 and 32 times, respectively, the maximum recommended human dose (MRHD) of 100 mg/day on a mg/m2 basis. Limited data indicate that sildenafil and its active metabolite are present in human milk. There is no information on the effects on the breastfed child, or the effects on milk production. Viagra is indicated for erectile dysfunction. Sexual stimulation is required.

Sildenafil is contraindicated in patients using any form of organic nitrate, either regularly or intermittently. Nitrates include nitroglycerin, isosorbide dinitrate, isosorbide mononitrate, and amyl nitrite. Administration of VIAGRA to patients using nitric oxide donors, such as organic nitrates or organic nitrites in any form, is contraindicated. Consistent with its known effects on the nitric oxide/cGMP pathway, VIAGRA was shown to potentiate the hypotensive effects of nitrates. Taking sildenafil with a nitrate can cause a sudden and serious drop in blood pressure. The contraindication covers regular use and intermittent use. VIAGRA is contraindicated in patients with a known hypersensitivity to sildenafil or any component of the tablet. Hypersensitivity reactions have been reported, including rash and urticaria.

Do not combine with other PDE5 inhibitors. 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 (0.5 g/kg) in healthy volunteers with mean maximum blood alcohol levels of 0.08%. Single oral doses of sildenafil up to 100 mg produced no clinically relevant changes in the ECGs of normal male volunteers. In healthy male volunteers, there was no evidence of a clinically significant effect of azithromycin (500 mg daily for 3 days) on the systemic exposure of sildenafil or its major circulating metabolite. No significant interactions were shown with tolbutamide (250 mg) or warfarin (40 mg). 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.

The most common adverse reactions reported in clinical trials (≥ 2%) are headache, flushing, dyspepsia, abnormal vision, nasal congestion, back pain, myalgia, nausea, dizziness, and rash. VIAGRA was administered to over 3700 patients (aged 19-87 years) during pre-marketing clinical trials worldwide. In fixed-dose studies, headache occurred in 16% at 25 mg, 21% at 50 mg, and 28% at 100 mg, versus 7% on placebo. Flushing occurred in 10% at 25 mg, 19% at 50 mg, and 18% at 100 mg, versus 2% on placebo. Dyspepsia occurred in 3% at 25 mg, 9% at 50 mg, and 17% at 100 mg, versus 2% on placebo. Abnormal vision occurred in 1% at 25 mg, 2% at 50 mg, and 11% at 100 mg, versus 1% on placebo. Nasal congestion occurred in 4% at 25 mg, 4% at 50 mg, and 9% at 100 mg, versus 2% on placebo. The type of adverse reactions in flexible-dose studies, which reflect the recommended dosage regimen, was similar to that for fixed-dose studies. In those flexible-dose trials, headache occurred in 16% on VIAGRA and 4% on placebo. Flushing occurred in 10% on VIAGRA and 1% on placebo. Dyspepsia occurred in 7% on VIAGRA and 2% on placebo.