A pre-existing defect in body temperature regulation may be a factor underlying some fatal reactions to the club drug ecstasy, researchers from Canada propose.
"Fatal MDMA intoxication is idiosyncratic and the reasons why some ecstasy users are especially susceptible to the toxic effects of the drug are still unknown," Dr Stephen Kish of the University of Toronto and the Centre for Addiction and Mental Health and colleagues point out.
They also note that deaths attributed to MDMA intoxication, which are fairly infrequent compared with the estimated number of recreational users, are often associated with a sharp increase of body temperature, also referred to as hyperthermia.
In the current issue of the Journal of Forensic Sciences, Kish's team describes a 24-year-old woman who developed fatal hyperthermia with complications affecting multiple organs after taking ecstasy. An autopsy showed that the woman had diffuse thyroid hyperplasia (also called Graves' disease), a thyroid disorder that could have made her less tolerant to heat.
Comprehensive drug screening showed only MDMA and traces of methamphetamine in a blood sample collected three to four hours after the woman took the drugs.
"Although a cause and effect cannot be established, as the thyroid hormone is a major regulator of thermogenesis, we suggest that hyperthyroidism predisposed the subject to ecstasy-induced hyperthermia," Kish and colleagues write.
This is in line with recent observations that chronically hyperthyroid rats, compared with rats with normal thyroids, have much higher maximum body temperatures and rates of death following exposure to ecstasy.
