MEANING / DEFINITION DRUG
Sildenafil citrate, sold as Viagra, Revatio and under various other trade names, is a drug used to treat erectile dysfunction and pulmonary arterial hypertension (PAH). It was originally developed by British scientists and then brought to market by the US-based pharmaceutical company Pfizer.[1] It acts by inhibiting cGMP-specific phosphodiest erase type 5, an enzyme that promotes degradation of cGMP, which regulates blood flow in the penis. Since becoming available in 1998, sildenafil has been the prime treatment for erectile dysfunction; its primary competitors on the market are tadalafil (Cialis) and vardenafil (Levitra).
Learn more :click the link http://en.wikipedia.org/wiki/Sildenafil
Vardenafil (INN) is a PDE5 inhibitor used for treating erectile dysfunction that is sold under the trade names Levitra (Bayer AG, GSK, and SP) and Staxyn.
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Tadalafil is a PDE5 inhibitor, currently marketed in pill form for treating erectile dysfunction (ED) under the name Cialis; and under the name Adcirca for the treatment of pulmonary arterial hypertension. It initially was developed by the biotechnology company ICOS, and then again developed and marketed world-wide by Lilly ICOS, LLC, the joint
venture of ICOS Corporation and Eli Lilly and Company.
Cialis tablets, in 5 mg, 10 mg, and 20 mg doses, are yellow,
film-coated, and almond-shaped. The approved dose for
pulmonary arterial hypertension is 40 mg (two 20-mg tablets)
once daily.Tadalafil is also manufactured and sold under the
name of Tadacip by the Indian pharmaceutical company
Cipla in doses of 10 mg and 20 mg.
Learn more :click the link http://en.wikipedia.org/wiki/Tadalafil
