Pregabalin Toxicity-Induced Posterior Reversible Encephalopathy Syndrome

Pregabalin, a prescription medication typically used for neuropathic pain, has increasingly been overused and abused. We present a unique case of a 51-year-old woman with a history of polysubstance use disorder and on methadone therapy who presented to the emergency department with altered mental status after consuming an unknown supratherapeutic amount of pregabalin. She was stabilized and discharged. Within 24 hours, she ingested another 1000mg of pregabalin, presenting again with altered mental status, along with tachycardia and hypertension. Computed tomography (CT) without contrast and fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR MRI) revealed subcortical white matter edema in the bilateral frontal and occipital lobes as well as the left parietal lobe, suggestive of posterior reversible encephalopathy syndrome (PRES). The patient recovered after four days of supportive treatment with an antihypertensive and an antiepileptic. PRES is a neurological phenomenon in which vasogenic edema, most commonly accumulating in the posterior parieto-occipital white matter, causes headaches, altered mental status, and seizures. To our knowledge, there has not been an established link between pregabalin toxicity and PRES, and the awareness of this potential complication can help in the early diagnosis and management of the disease to prevent further progression.