Montelukast is the generic form of the brand-name medication Singulair. It is a receptor blocker used to treat asthma, exercise-induced asthma, hay fever, and allergies by reducing constriction and inflammation in the lungs.

Founded in 1986, Macleods Pharmaceuticals distributes about 62 drugs in the U.S. Macleods serves about 80 countries through its range of product offerings. The company has 2 manufacturing sites in India.