Do not stop taking sildenafil without talking to your doctor. Rarely reported side effects include: an erection that will not go away priapism. Store mixed oral liquid in the refrigerator. Data shared with Viatris will be aggregated and de-identified; it will be combined with data related to other Savings Offer redemptions and will not identify you Viatris reserves the right to rescind, revoke, or amend this Savings Offer without notice No membership fees. Adults 65 years of age and older—25 mg as a single dose no more than once a day, 1 hour before sexual intercourse. When hypertension occurs in the lungs, the heart must work harder to pump enough blood through the lungs.Sildenafil (Viagra) is used to treat erectile dysfunction (impotence; inability to get or keep an erection) in men. Sildenafil (Liqrev, Revatio) is used to improve the ability to exercise in adults (Liqrev, Revatio) and children 1 year of age and older (Revatio) with pulmonary arterial hypertension (PAH; high blood pressure in the vessels carrying blood to the lungs, causing shortness of.  · For oral dosage form (tablets): Adults up to 65 years of age—50 milligrams (mg) as a single dose no more than once a day, 1 hour before sexual intercourse. Alternatively, the medicine may be taken 30 minutes to 4 hours before sexual intercourse. Your doctor may adjust your dose if needed. Sildenafil is used to treat male sexual function problems (impotence or erectile dysfunction-ED). In combination with sexual stimulation, sildenafil works by increasing blood flow to the penis to.