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Dosage

Viagra pills are blue and diamond-shaped with the words "Pfizer" engraved on one side, and "VGR xx" (where xx stands for "25", "50" or "100", the dose of that pill in milligrams) engraved on the other. The dose of sildenafil for erectile dysfunction is 25 mg to 100 mg taken not more than once per day between 30 minutes and 4 hours prior to sexual intercourse.

The dosage for pulmonary arterial hypertension (Revatio) is one 20 mg tablet three times a day. Revatio pills are white, round, film-coated tablets imprinted with "RVT 20" embossed on one side.

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