Five Deaths Resulting from Abuse of Dextromethorphan Sold Over the Internet

Abstract

Dextromethorphan is a widely available over-the-counter antitussive that produces intoxicating, hallucinogenic, and dissociative effects at doses significantly exceeding the therapeutic range. We report the deaths of five teenage males in three incidents in three states (WA, FL, and VA) who purposefully ingested large doses of dextromethorphan for recreational purposes and died as a result of the direct toxic effects of the drug. The dextromethorphan was obtained from the same internet supplier in each case. Postmortem blood dextromethorphan concentrations ranged from 950 to 3230 ng/mL (median 1890 ng/mL). Three subjects had diphenhydramine present, one had a trace of alprazolam, and two were positive for cannabinoids. In each case, the death was attributed to dextromethorphan toxicity or toxicity from dextromethorphan and other drugs. The article discusses the metabolism, pharmacology, and potential for drug interactions for dextromethorphan and the likely mechanisms for toxicity. The dextromethorphan concentrations in all five subjects significantly exceeded the therapeutic range and are consistent with concentrations reported in other cases of dextromethorphan abuse and toxicity. The deaths resulted in the prosecution of three individuals involved in sale or distribution of the drug.