VIAGRA

Viagra, proprietary name for sildenafil citrate, a drug used to treat impotence in men. It has been shown to be effective as the only orally prescribed drug that can increase the body’s ability to achieve and maintain an erection. Taken as a tablet one to four hours before sexual activity, Viagra works by enhancing the effect of nitric oxide into the corpus cavernosum (erectile tissue) of the penis. This enables smooth muscle relaxation of the corpus cavernosum, and allows inflow of blood, thereby initiating and maintaining the erectile mechanism.

Viagra has no effect in the absence of sexual stimulation. It is prescribed only after a full assessment has been made of the possible underlying causes of the patient’s impotence. It is not suitable for patients with a history of cardiovascular disorders; because it lowers blood pressure, it can not be used along with treatments containing nitrates (such as nitroglycerine, prescribed for angina).

In less than a year after the launch of the drug by the Pfizer company in the United States in March 1998, some 3.6 million prescriptions for Viagra had been issued in that country. It was licensed for use in the European Union in September 1998. In the United Kingdom it is available on prescription through the National Health Service.

 

........back