Leukotriene Antagonists

Include the leukotriene receptor antagonists montelukast, zafirlukast, and pranlukast (not available in USA) as well as the 5-lipoxygenase (5-LO) inhibitor zileuton. Montelukast is the most commonly used drug of this class in USA.

Montelukast is a once-daily oral drug approved for the prevention of exercise-induced bronchospasm.

Most commonly used as adjuvant anti-inflammatory agents in the treatment of chronic asthma in addition to inhaled corticosteroids.

Mixed evidence exists for the use of leukotriene antagonists for other lung diseases, such as COPD, interstitial lung diseases, and obstructive sleep apnea.

These drugs may have a possible benefit in various malignancies as well as pulmonary and systemic vascular diseases; studies are ongoing.

Small risk (1.9%) of hepatic dysfunction in pts on zileuton. LFTs are usually monitored in these pts.

Small risk of increased INR in pts taking zileuton and warfarin.

Potentiation of effects of warfarin, theophylline, and propranolol with zileuton.

Pts on any of these second-line asthma therapies may have more severe asthma at baseline and may be more prone to bronchoconstriction/bronchospasm in the periop period.