Phenytoin Toxicity in an Older Patient with Slow Metabolism and Atypical Presentation

Abstract

Phenytoin toxicity occurred in an older man who received a dosage of 300 mg/day. The patient developed high serum phenytoin concentrations from this common adult dosage, with symptoms of functional decline and altered mental status. These behaviors were perceived as sun‐downing and were treated with haloperidol. A long hospitalization was required.