Atenolol is the generic form of the brand-name medication Tenormin. It is used to treat high blood pressure and chest pain following a heart attack by relaxing blood vessels and improving blood flow.

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.