 There are currently three different types of drugs within the CysLT1 family, zafirlukast which was first on the market being released in 1996,  montelukast which was released in 1998 and pranlukast which was released in 2007.The medical uses for Cysteinyl-leukotriene type 1 receptor antagonists are for chronic and prophylactic treatment of asthma.Other indications have been approved by the FDA for montelukast and they are used for the prevention of exercise-induced bronchoconstriction (EIB), relief of symptoms of allergic rhinitis (AR) that is for relief of seasonal allergic rhinitis and perennial allergic rhinitis (PAR).