1. For adults, the recommended starting oral dose is 10 mg, taken once daily, 25 to 60 minutes prior to sexual activity. Based on efficacy and tolerability, the dose may be adjusted to 5 mg or 20 mg. The maximum recommended dose is 20 mg per day. (1) Dosage in Renal Impairment: No dose adjustment is required for patients with renal impairment. (2) Dosage in Hepatic Impairment: For patients with mild hepatic impairment, no dose adjustment is required; for patients with moderate hepatic impairment, the recommended starting dose is 5 mg, which may subsequently be gradually increased to 10 mg based on efficacy and tolerability; for patients with severe hepatic impairment, the appropriate dosage has not yet been established.
2. Dosage in the Elderly: For patients aged 65 years and older, the starting dose should be lower (5 mg).
3. Dosage in Dialysis: For patients requiring renal dialysis due to end-stage renal disease, the appropriate dosage has not yet been established.