Indications and Usage for Viagra

Viagra is indicated for the treatment of erectile dysfunction.
Viagra Dosage and Administration
Dosage Information

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 30 minutes to 4 hours before sexual activity.

The maximum recommended dosing frequency is once per day.

Based on effectiveness and toleration, the dose may be increased to a maximum recommended dose of 100 mg or decreased to 25 mg.
Use with Food

Viagra may be taken with or without food.
Dosage Adjustments in Specific Situations

Viagra was shown to potentiate the hypotensive effects of nitrates and its administration in patients who use nitric oxide donors such as organic nitrates or organic nitrites in any form is therefore contraindicated [see Contraindications (4.1), Drug Interactions (7.1), and Clinical Pharmacology (12.2)].
Slideshow: Viagra: 11 Interesting Facts That You Can't Help But Be Amazed By
Viagra: 11 Interesting Facts That You Can't Help But Be Amazed By

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 25 mg [see Warnings and Precautions (5.5), Drug Interactions (7.2), and Clinical Pharmacology (12.2)].
Dosage Adjustments Due to Drug Interactions

Ritonavir

The recommended dose for ritonavir-treated patients is 25 mg prior to sexual activity and the recommended maximum dose is 25 mg within a 48 hour period because concomitant administration increased the blood levels of sildenafil by 11-fold [see Warnings and Precautions (5.6), Drug Interactions (7.4), and Clinical Pharmacology (12.3)].

CYP3A4 Inhibitors

Consider a starting dose of 25 mg in patients treated with strong CYP3A4 inhibitors (e.g., ketoconazole, itraconazole, or saquinavir) or erythromycin. Clinical data have shown that co-administration with saquinavir or erythromycin increased plasma levels of sildenafil by about 3 fold [see Drug Interactions (7.4) and Clinical Pharmacology (12.3)].
Dosage Adjustments in Special Populations

Consider a starting dose of 25 mg in patients > 65 years, patients with hepatic impairment (e.g., cirrhosis), and patients with severe renal impairment (creatinine clearance <30 mL/minute) because administration of Viagra in these patients resulted in higher plasma levels of sildenafil [see Use in Specific Populations (8.5, 8.6, 8.7) and Clinical Pharmacology (12.3)].
Dosage Forms and Strengths

Viagra is supplied as blue, film-coated, rounded-diamond-shaped tablets containing sildenafil citrate equivalent to 25 mg, 50 mg, or 100 mg of sildenafil. Tablets are debossed with PFIZER on one side and VGR25, VGR50 or VGR100 on the other to indicate the dosage strengths.

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