Attenuation of MDMA-induced hyperthermia by ethanol in rats depends on ambient temperature

In rats, at ambient temperatures of 21-23 °C, ethanol can attenuate the hyperpyretic effects of MDMA. We assessed if this attenuation holds true at a high ambient temperature. Rats were given MDMA (6.6 mg/kg i.p.) with or without ethanol (1.5 g/kg i.p.) at a room temperature of 32 °C. In the MDMA and ethanol + MDMA rats, body temperatures rose to about 42 °C after 60 min; all these rats had died after 120 min. At 23 °C, however, there was no lethality and ethanol reduced the hyperthermia. Thus, the effects of ethanol on MDMA-induced hyperthermia are related to ambient temperature.