Drug Interaction Between Phenytoin and Valproic Acid in a Child With Refractory Epilepsy: A Case Report

Discussion:
Despite the appropriate phenytoin concentration in the capsules, the patient presented with phenytoin toxicity. This toxicity likely resulted from the drug interaction between phenytoin and valproic acid that leads to phenytoin displacement from plasmatic proteins and inhibits phenytoin metabolism, thereby increasing the concentration of free drug in the serum.

Source: Journal of Pharmacy Practice - March 19, 2014 Category: Drugs & Pharmacology Authors: Carvalho, I. V., Carnevale, R. C., Visacri, M. B., Mazzola, P. G., de Fatima Lopes Ambrosio, R., Reis, M. C. d., de Queiroz, R. A., Moriel, P. Tags: Adverse Drug Events Source Type: research