Fixed drug eruption due to dextromethorphan with tolerance to other opioids.

Dextromethorphan is a synthetic morphine derivative used as a cough suppressant in the form of hydrobromide salt. It is widely used, either alone or in combination with other compounds, but there have been few published reports of adverse cutaneous reactions. Only 2 cases of fixed drug eruption (FDE) due to dextromethorphan have been reported in the literature [1,2] and neither of them evaluated possible cross-reactivity with other opioids. A 63-year-old man, with no history of atopy, started treatment with a combination drug (dextromethorphan 15 mg + acetaminophen 500 mg) for a common cold