The recommended dose is 50 mg taken as needed approximately one hour before sexual activity. The dose may be adjusted to 25 mg or 100 mg based on efficacy and tolerability.

Yes, it is contraindicated in patients for whom sexual activity is inadvisable due to severe cardiovascular disorders, such as unstable stenocardia or severe cardiac failure.

Yes, co-administration with nitrates in any form or nitric oxide donors is strictly contraindicated due to the potentiation of hypotensive effects.

For patients with severe renal impairment (creatinine clearance <30 mL/min), a 25 mg starting dose should be considered.