Repeated use of MDMA (ecstasy) may cause long-lasting changes to the brain's serotonin system, but these changes could be reversible over time. Brain scans using PET show reduced availability of serotonin transporters in people who have used MDMA, suggesting damage to serotonin-producing neurons. The study also finds that women are more vulnerable than men to these MDMA-induced alterations. The findings support the idea that MDMA use leads to protracted changes in the serotonergic system, but the reduced serotonin transporter availability might recover with abstinence.
Heavy ecstasy (MDMA) use is associated with lasting verbal memory deficits and elevated psychological symptoms even after more than 2.5 years of abstinence, while reduced serotonin transporter availability in the brain may partially recover when use stops. In a longitudinal study comparing current ecstasy users, ex-users, polydrug controls, and drug-naive controls over two years, ex-users showed the worst verbal memory and highest symptom scores, with no improvement over time. Current users' memory and symptoms did not worsen during continued use. Serotonin transporter availability in the midbrain recovered as current users reduced MDMA use, but this recovery may not reflect neuronal integrity. Pre-existing differences cannot be ruled out as an alternative explanation.