Bupropion Toxicity Presenting As Alcohol Withdrawal Syndrome: A Case Report

Bupropion toxicity can present as neurologic and autonomic manifestations that closely resemble alcohol withdrawal syndrome, a diagnostic challenge that becomes compounded when patients are unable to provide reliable histories and when confirmatory toxicology results are delayed. We present the case of a 55-year-old male who presented with agitation, encephalopathy, auditory and visual hallucinations, hypertension, tremors, and suspected seizure activity. Based on his substance use history and clinical presentation, he was managed as alcohol withdrawal using symptom-triggered benzodiazepines per the Clinical Institute Withdrawal Assessment for Alcohol-Revised protocol. Serum ethanol level and urine toxicology screen were negative on admission, and he improved with supportive care and benzodiazepine therapy in the intensive care unit. Serum toxicology results returned after discharge and revealed markedly elevated bupropion and hydroxybupropion concentrations, establishing clinically significant bupropion toxicity as the true etiology. While bupropion toxicity mimicking alcohol withdrawal has been described, cases in which the diagnosis was established only after discharge, when quantitative metabolite assays returned, remain rare. This case illustrates how convincingly bupropion toxicity can masquerade as alcohol withdrawal syndrome, and how antidepressant toxicity belongs on the differential in any patient presenting with unexplained encephalopathy and autonomic instability, particularly when a reliable history is unavailable. Early recognition of bupropion toxicity, even when confirmatory testing is pending, can guide appropriate cardiac monitoring and anticipatory seizure management, and help avoid unnecessary escalation of alcohol withdrawal-directed therapy.