Minor
Suspected
Mô tả
Phenytoin, a potent CYP inducer, can increase the metabolism of montelukast, potentially reducing its plasma levels and therapeutic efficacy.
Cơ chế
Phenytoin induces CYP2C8 and CYP3A4, the principal enzymes responsible for montelukast oxidative metabolism, accelerating clearance and reducing AUC.
Ý nghĩa lâm sàng
The interaction is predicted based on known enzyme induction by phenytoin; formal pharmacokinetic studies in humans are lacking but CYP induction by phenytoin is well established.
Xử trí
Monitor asthma or allergic rhinitis control in patients starting or stopping phenytoin; consider increasing montelukast dose if symptom breakthrough occurs.