There is a problem with information submitted for this request. Click here for an email preview. Your doctor may adjust your dose if needed. Recent heart or blood vessel problems. If too much is used, the chance of side effects is increased.Strengths: 25 mg, 50 mg, mg; Brand: Viagra. Form: oral tablet; Strengths: 25 mg, 50 mg, mg; Adult dosage (ages 18–64 years) Typical dosage: . For most men, the recommended dose is 50 mg. Your doctor will start you on the VIAGRA dose he or she thinks is right for you.  · 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 .