Answer
Oxcarbazepine and MHD inhibit CYP2C19, and oxcarbazepine (Trileptal) doses above 1,200 mg/day increased phenytoin plasma levels by up to 40%, potentially requiring a reduction in the phenytoin dose.
Sources for this answer
- Trileptal 150 mg, 300 mg, 600 mg Film-coated tabletsNovartis Pharmaceuticals UK Ltd · emc · SmPC §4.5 Interaction with other medicinal products · Version 32Document updated
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