It works for up to 36 hours. These small differences affect the way each medication works, such as how quickly it takes effect and wears off, and the possible side effects. They’re often the first line of treatment for trouble getting or keeping an erection, called erectile dysfunction ED. Talk to your doctor if you take too much sildenafil and you’re worried about any of these side effects: headaches. Recent heart or blood vessel problems. For treatment of erectile dysfunction: 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. For erectile dysfunction, it’s best to take sildenafil on an empty stomach.Sildenafil (Viagra). This medicine works best when you take it on an empty stomach an hour before sex. The body takes longer to absorb it after a high-fat meal or alcohol. Its effects . Take sildenafil up to 4 hours before you want to have sex. For sildenafil to work properly, you’ll need to be sexually excited. Dosage and strength for pulmonary hypertension . FAQ What is Viagra? Viagra relaxes muscles found in the walls of blood vessels and increases blood flow to particular areas of the body. Viagra is used to treat erectile .
