Adults 65 years of age and older—25 mg as a single dose no more than once a day, 1 hour before sexual intercourse. Its use is not studied in patients with severe hepatic impairment. Do not keep outdated medicine or medicine no longer needed. Children 1 year of age and older weighing 20 kg or less—10 mg 3 times a day. PDE5Is reduce systemic and pulmonary arterial pressures and cardiac output thereby having vasodilator effects to increase blood flow to the penis to help a man get and keep an erection. Ask your doctor if you have any questions.Sildenafil oral tablet is available as a brand-name drug and as a generic drug. Brand names: Viagra, Revatio. Sildenafil comes in three forms: an oral tablet, an oral suspension (liquid), and an. This list shows exclusive savings for the most common prescriptions in the Kroger Health Savings Club. Don’t see your prescription on the list? Try searching for it above. You . Sildenafil is used to treat erectile dysfunction (ED) and to reduce blood pressure in pulmonary arterial hypertension (PAH). It is taken when needed for ED and daily for PAH. A headache, stomach upsets, and flushing are the main side effects, and it should not be taken within 24 hours of a nitrate. 5. Tips.