Reinforcing Effects of MDMA (‘Ecstasy’) in Drug-Naive and Cocaine-Trained Rats

Abstract

3,4-Methylenedioxymethamphetamine (MDMA; ‘ecstasy’) is one of the most prevalent illegal drugs of abuse among European adolescents, a population not generally experienced with respect to ‘hard’ drugs such as cocaine. We, therefore, determined the reinforcing effect of intravenously self-administered MDMA in a fixed ratio 1 time-out 150 s schedule of reinforcement in rats that were truly drug naive and compared it to cocaine-trained rats. The reinforcing effect of MDMA [0.032–10 mg/(kg·injection)] did not differ between drug-naive rats and cocaine-trained ones. MDMA sensitized the animals to its own rate-increasing effect but not to that of cocaine. When MDMA was tested after cocaine, there was no carryover of cocaine’s reinforcing effect to that of MDMA, suggesting that MDMA and cocaine produce distinct interoceptive stimuli in rats.

In the evidence

This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.

• State of the evidence: MDMA for addiction ↓Opposes

  Intravenous MDMA was self-administered with equal reinforcing effect in drug-naive and cocaine-trained rats, and MDMA and cocaine produced distinct interoceptive stimuli.

  Synthesized October 22, 2026

Comparable studies

Other preclinical and animal studies on MDMA for addiction, most cited first.