A new rat study has found that a moderate dose of MDMA (ecstasy or Molly) that is typically nonfatal in cool, quiet environments can be deadly in the hot, crowded, social settings where the drug is often taken by people.

Previous studies have shown that high doses of MDMA increase body temperature, while results with moderate doses have been inconsistent. This study, published in the Journal of Neuroscience, shows that even moderate doses of MDMA taken in warm, crowded environments can be dangerous because it interferes with the body’s ability to regulate temperature.

“We know that high doses of MDMA can sharply increase body temperature to potentially lead to organ failure or even death,” said Dr. Nora D. Volkow, director of the National Institute on Drug Abuse. “However, this current study opens the possibility that even moderate doses could be deadly in certain conditions.”

For the study, scientists gave rats low to moderate doses of MDMA found to be nonfatal in past studies. The researchers watched for drug-induced changes in the rats’ brain and body temperature and in the body’s ability to cool itself through blood vessel dilation.

They found that when the rats were alone and in a cooler environment, a moderate dose of MDMA modestly increased brain and body temperature and moderately lowered the rats’ ability to eliminate extra heat.

When rats received the same dose of MDMA in a warmer environment or in the presence of another rat in the cage, however, their brain temperature increased, causing some of the rats to die. The situation proved fatal because the drug interfered with the body’s ability to get rid of extra heat.

“These results demonstrate that the use of MDMA in certain warm, social settings could be more dangerous than commonly believed,” said first author Dr. Eugene Kiyatkin. “Even with moderate doses, we saw drug-induced, fatal brain hyperthermia during conditions of social interaction and in warm environments.”

These findings suggest that treatments designed to increase the efficiency of whole-body cooling by targeting blood vessel constriction in the skin could effectively reverse hyperthermia caused by MDMA.

This study was conducted by researchers at the National Institute on Drug Abuse’s Intramural Research Program (NIDA IRP), part of the National Institutes of Health.

Source: National Institute on Drug Abuse