WebMay 18, · Generic: Sildenafil Form: oral tablet Strengths: 25 mg, 50 mg, mg Brand: Viagra Form: oral tablet Strengths: 25 mg, 50 mg, mg Adult dosage (ages .On 6 May , Pfizer , which manufactures Viagra, told the Associated Press they will begin selling the drug directly to people on its website. If you are taking sildenafil for PAH, take the missed dose as soon as you remember it. From Mayo Clinic to your inbox Sign up for free and stay up to date on research advancements, health tips, current health topics, and expertise on managing health. Sildenafil belongs to a group of medicines called phosphodiesterase 5 PDE5 inhibitors. Retrieved 6 October It added further: “As a matter of policy and sound statutory interpretation, patentees cannot be allowed to ‘game’ the system in this way. When a man is sexually stimulated, his body’s normal response is to increase blood flow to his penis to produce an erection.WebSildenafil (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 . WebMay 18, · Generic: Sildenafil Form: oral tablet Strengths: 25 mg, 50 mg, mg Brand: Viagra Form: oral tablet Strengths: 25 mg, 50 mg, mg Adult dosage (ages . WebOct 6, · Sildenafil is used to treat men who have erectile dysfunction (also called sexual impotence). Sildenafil belongs to a group of medicines called phosphodiesterase .Your doctor will tell you not to take sildenafil if you are taking street drugs containing nitrates. The substance is the same under both trade names. Take sildenafil as needed before sexual activity. Do not take a double dose to make up for a missed one. Men between the ages of 30 and 65 would be eligible to buy four tablets after a consultation with a pharmacist.