Oxcarbazepine appears to lower
lamotrigine levels by about 15 to 75%.
Lamotrigine appears to increase the levels of the active
metabolite of
oxcarbazepine.
The
clinical relevance is uncertain, but it would seem likely that some patients will have significantly reduced
lamotrigine levels. Monitor concurrent use carefully, being aware that dosage adjustments may be necessary. The importance of the increase in
oxcarbazepine metabolite levels is less clear.