Serotonin syndrome with tramadol and dextromethorphan

Abstract

Serotonin syndrome is an iatrogenic drug-induced synaptic serotonin concentration related toxidiome. A 29-year-old man developed agitation, tachycardia and myoclonus of limbs after an intramuscular injection of 100 mg tramadol. He had recently been given multiple medications, including dextromethorphan (DXM) by a private doctor for flu-like symptoms. The patient was stabilised with diazepam, midazolam and supportive treatment. Both tramadol and DXM could cause the serotonin syndrome, but usually in combination with monoamine oxidase inhibitors or serotonin reuptake inhibitors. This was the first reported case in the English literature of serotonin syndrome with tramadol and DXM. Therefore, a detailed drug history and knowledge of potential serotonergic drugs are important.