Montelukast is ?

Ans. is 'a' i.e., Leukotriene antagonist Leukotriene antagonists Monteleukast and zafirleucast are cystenyl LT, (cys LT1) receptor antagonists. They are indicated for prophylactic therapy of mild to moderate asthma as alternatives to inhaled glucocoicoids. They are more acceptable in children. They are not used for terminating asthma episodes. They are effective in aspirin induced asthma. They are very safe drugs, produce few side effects like headache and rashes. Eosinophilia, neuropathy and churg-strauss syndrome are other rare side effects.