Biochem/physiol Actions Zafirlukast is a potent subtype specific cysteinyl leukotriene type 1 receptor (CysLT1) antagonist; antiasthmatic. Zafirlukast has over 1000-fold selectivity for CysLT1, one of two receptors for cysteinyl leukotrienes LTC4, LTD4, and LTE4, which are important mediators of human bronchial asthma. |