Leukotriene Receptor Antagonists

Indication: Prophylaxis and Chronic treatment of asthma in adults and children 12 years of age and older

MOA: selective and competitive leukotriene receptor antagonist of leukotreine D4 and E4 which are components of slow-reacting substance of anaphylaxis (SRSA) preventing bronchoconstriction

Extensively metabolized by CYP2C9 yet inhibits CYP3A4 and CYP2C9

Don't use to treat acute attacks, nursing women should NOT use this drug 

One hour before or two hours after a meal.

Indications: Prophylaxis and Chronic treatment of asthma in adults and children one year of age and older, 4mg oral granules for children .5-5 years old for perennial allergic rhinitis

MOA: Selective and competitive CysLT1 receptor antagonist of leukotriene C3, D4, and E4 which are components of slow-reacting susbtance of anaphylaxis (SRSA) preventing bronchoconstriction

Metabolized by CYP2C9 and CYP3A4

Indications: Prophylaxis and chronic treatment of asthma in adults 12 years of age or older

MOA: orally active inhibitors of 5-lipoxygenase, the enzyme that catalyzes the formation of leukotrienes from arachidonic (LTB4, LTC4, LTDD4, and LTE4)---both the R(+) and S(-) enantiomers are pharmacologically active

contraindicated in patients with active liver disease or persistant ALT elevations

Drug interactions with theophylline and warfarin