Oral phenytoin toxicity causing sinus arrest: a case report

We present a case of sinus node arrest leading to symptomatic junctional bradycardia from oral phenytoin toxicity, which is a rare presentation. Our patient had no prior cardiac history and was on phenytoin therapy for seizure disorder. Although bradycardia is more commonly associated with intravenous phenytoin and there were few case reports of bradycardia with oral phenytoin reported, the literature is limited. In this case report, we also reviewed the pathophysiology of phenytoin-induced cardiac toxicity.