CARBAMAZEPINE AND TOPIRAMATE

Topiramate serum levels may be reduced by about 40% by carbamazepine. Carbamazepine levels are not affected by topiramate. However, one report suggests that the toxicity seen when topiramate was added to the maximum tolerated doses of carbamazepine may respond to a reduction in the carbamazepine dose.
Monitor the outcome of concurrent use, increasing the topiramate dose if it seems less effective than desired.