Usual Recommended Oral Dose: 50 mg taken, as needed, approximately one hour before sexual activity.
Sildenafil may be taken anywhere from 4 hours to 30minutes before sexual activity.
Sildenafil dose may be increased to the maximum recommended oral dose of 100 mg or decreased to 25 mg based on patient response and tolerance.
Maximum Recommended Dose: 100 mg.
Maximum Recommended Dosing Frequency: Once a day.
Sildenafil plasma levels are increased in patients with the following conditions: Age >65 years; Severe liver impairment (e.g., cirrhosis); Severe kidney impairment (creatinine clearance <30 mL/min); Concomitant use of potent cytochrome P450, 3A4 inhibitors (e.g., ketoconazole, itraconazole, erythromycin, saquinavir).
A starting dose of 25 mg should be considered in these patients.
Make sure that patients who are taking alpha-blockers concomitantly with sildenafil are stable on alpha-blocker therapy before starting treatment with sildenafil. Initiate sildenafil at the lowest possible dose in these patients.