A 3-year-old female patient developed chorea possibly due to an interaction between phenytoin, phenobarbital and clobazam used for generalized tonic clonic seizures. Phenytoin withdrawal resulted in recovery within 24 hours. Post reaction computerized tomography (CT)-scan of brain was normal. Combined use of anti-seizure drugs and interactions between them may be responsible for the reaction. Therapeutic drug monitoring is important while prescribing two or more anti-seizure drugs.
Keywords: Adverse drug reaction; anti-seizure drugs; chorea; drug interactions; phenytoin.