Although
MDMA (ecstasy) is a relatively safe
recreational drug and is currently considered for
therapeutic use for the treatment of
posttraumatic stress disorder (
PTSD) and
alcohol use disorder (AUD), recreational
MDMA use occasionally elicits
hyperthermia and
hyponatremia, sometimes with a fatal outcome. Specific risk factors for both adverse effects are profuse sweating while vigorously dancing under unfavorable conditions such as high ambient temperatures and insufficient fluid suppletion which result in
dehydration. Concomitant use of
MDMA and alcohol is highly prevalent, but adds to the existing risk, because alcohol facilitates the emergence of
MDMA-induced adverse events, like
hyperthermia,
dehydration, and
hyponatremia. Because of potential health-related consequences of concomitant use of
MDMA and alcohol, it is important to identify the mechanisms of the interactions between alcohol and
MDMA. This review summarizes the main drivers of
MDMA-
induced hyperthermia,
dehydration, and
hyponatremia and the role of concomitant alcohol use. It is shown that alcohol use has a profound negative impact by its interaction with most of these drivers, including poikilothermia, exposure to high ambient temperatures, heavy exercise (vigorous dancing), vasoconstriction,
dehydration, and delayed initiation of sweating and diuresis. It is concluded that recreational and clinical
MDMA-users should refrain from concomitant drinking of alcoholic beverages to reduce the risk for adverse health incidents when using
MDMA.