The hard facts on Viagra

Viagra is one brand name of a drug that is used to treat erectile dysfunction (impotence): the inability to get, and maintain, an erection. It is also used in the treatment of high blood pressure specific to the heart and the arteries that feed the lungs. The generic name of the drug is sildenafil (pronounced sill-den-a-fill). Viagra works by binding to an enzyme called phosphodiesterase. Viagra binding to the enzyme prevents it from converting the chemical cyclic guanosine monophosphate (abbreviated cGMP) into guanosine triphosphate (GTP). Viagra is one of the most counterfeited medicines in the world. Because of its wide appeal many patients attempt to buy it without a prescription. Viagra can be bought from online auction sites, internet pharmacies and even bricks-and-mortar retail stores. There are numerous risks in taking counterfeit Viagra. Fake tablets can contain no Viagra or too much Viagra. There have also been reports that counterfeit tablets have contained blue printer ink – to give them that genuine Viagra look – illegal drugs like amphetamines, and other unrelated drugs like the antibiotic metronidazole.