Abstract

ACUTE ENCEPHALOPATHY FROM PHENYTOIN TOXICITY

Aliya Varghese* and Angel Mariam Wilson

ABSTRACT

Phenytoin is a commonly used drug in the treatment of generalized tonic-clonic seizures, complex partial seizures, status epilepticus, trigeminal neuralgia, and behaviour disorders. Its non-linear kinetics resulting from saturable enzymatic metabolism is the major cause for toxicity. Phenytoin toxicity can result in altered mental status, confusion, slurring of speech, nystagmus, diplopia, ataxia, and dystonia. Here we report a case of acute encephalopathy from phenytoin toxicity in a 69-year-old adult due to chronic administration. Patient was presented with unsteadiness and swaying to either side while walking and also had nystagmus and gingival hyperplasia. Based on the signs and symptoms the patient was diagnosed to have acute encephalopathy from phenytoin toxicity. Symptoms resolved graduallyafter withdrawing the drug and alternative antiepileptic drug was added. This case report highlights the importance of proper education of patients and their representatives for timely provision of adequate treatment and the role pharmacists can play in ensuring medication safety and adherence.

Keywords: Phenytoin toxicity, Encephalopathy, Hyperammonaemia, Nystagmus, Gingival hyperplasia.