Treatment of caffeine toxicity with metoprolol.

A 27-year-old man presented with an intentional overdose of concentrated caffeine powder that he bought over the internet. The patient received benzodiazepines and ondansetron for symptomatic treatment when he arrived in the Emergency Department (ED). Subsequently, he developed recurrent supraventricular tachycardia in the ED. The SVT was successfully treated with metoprolol. The patient's caffeine level was >90 mg/L. This is the first known report of treatment of caffeine-induced supraventricular tachycardia with metoprolol.