Neurologic toxicity of carbamazepine in treatment of trigeminal neuralgia

Carbamazepine is a medication used to treat a variety of neurological and psychiatric conditions including seizure disorders, neuropathic pain syndromes, and bipolar disorder. Unfortunately, its pharmacokinetics and side effect profile may lead to significant toxicities due to its sodium channel blockade. In 2019, there were over 1500 cases of isolated carbamazepine toxicity reported to poison centers across the United States. Carbamazepine toxicity may result in vague neurological symptoms in milder cases, but in severe toxicity, it can cause cardiovascular instability, intractable seizures, and coma. In this article, we describe a case of a 40-year-old female who presented to a local emergency department with focal neurological deficits after repeated supratherapeutic dosing of carbamazepine.. This case highlights a key cerebrovascular accident mimic that emergency physicians should consider from acute toxicity that can be seen with carbamazepine in a patient who was taking the medication as prescribed.