Abstract
Intravenous phenytoin (PHT) for suspected seizures may trigger severe choreoathetosis. Discontinuation of PHT results in immediate and complete resolution of hyperkinesias. Co-medication with valproic acid, levetiracetam, tranquilisers, and anesthetics or alcohol presumably do not modify this adverse effect of PHT. Choreoathetosis can be easily misinterpreted as seizures.