Drug-Drug

• May inhibit the CYP 2C19 enzyme system and would be expected to alter the effects of other drugs that are metabolized by this system. Oxcarbazepine and MHD induce the P450 3A4/5 enzyme systems and would be expected to alter the effects of other drugs that are metabolized by this system. This may result in ↓ levels and effectiveness of hormonal contraceptives , felodipine , isradipine , nicardipine , nifedipine , nimodipine , and cyclosporine . In addition, oxcarbazepine itself is metabolized by cytochrome P450 system and other drugs that alter the activity of this system .

• ↑ CNS depression may occur with other CNS depressants, including alcohol , antihistamines , antidepressants , sedative/hypnotics , and opioids .

• Carbamazepine , phenobarbital , phenytoin , valproic acid , and verapamil ↓ levels.

• May ↑ serum levels and effects of phenytoin (dose ↓ of phenytoin may be required).