Sildenafil

Prescription use: Sildenafil is a prescription PDE5 inhibitor used to treat erectile dysfunction. It supports an erection by increasing penile blood flow during sexual stimulation and does not work without stimulation.

Typical prescribed dosage: The usual starting dose is 50 mg approximately one hour before sexual activity. It may be taken from 30 minutes to four hours beforehand. A clinician may adjust the dose between 25 mg and 100 mg. The maximum recommended frequency is once daily.

Important warning: Sildenafil must not be combined with nitrates or riociguat because this can cause a serious reduction in blood pressure. Seek emergency care for an erection lasting longer than four hours.