Sildenafil is the generic form of the brand-name medication Viagra. Sildenafil is a certain type of enzyme inhibitor used to treat erectile dysfunction (ED).

Founded in 1961, Mylan Pharmaceuticals is the second largest provider in the U.S. and distributes more than 388 drugs in the country. Mylan serves 165 countries in total through its range of product offerings. The company has 40+ manufacturing sites including in the U.S., India, and Ireland.