Baclofen is a structural analogue of gamma-aminobutyric acid with central myorelaxant effect. Ingestion of a toxic dose of baclofen induces a clinical presentation with neurological, cardiac, respiratory and metabolic expression, sometimes life-threatening. The authors present the case of a 17-year old teenage girl who developed deep coma, sinus bradycardia, fi rst-degree atrioventricular block, arterial hypertension and hyperglycemia after ingesting a large dose of baclofen. The patient was successfully treated with supportive measures. Early diagnosis and prompt therapeutic intervention are key-steps in the management of acute baclofen poisoning.