3 Clinical psychopharmacology3.3 Pharmacodynamics
3.3.2.12 Empathogens and MDMA
2 min read
Written by Resident Doctor Committee · Published
New in the 2027 syllabus
The College added this topic for exams from January 2027.
What empathogens are
Empathogens (also called entactogens) make people feel emotionally open and close to others. The term describes effects, not a single receptor mechanism.
3,4-Methylenedioxymethamphetamine (MDMA) is an amfetamine derivative. As well as its typical social and emotional effects, it is a stimulant and alters perception.
How MDMA works
MDMA acts on presynaptic transporters to release serotonin and noradrenaline, with a smaller effect on dopamine.
Classic psychedelics work mainly as agonists at the serotonin 5-HT2A receptor. MDMA's monoamine-releasing action sets it apart from them.
Effects and toxicity
Effect | What you see clinically |
|---|---|
Sympathetic activation | Fast heart rate, high blood pressure, sweating and jaw clenching |
Raised temperature | Hyperthermia, sometimes with rhabdomyolysis (muscle breakdown) and organ damage |
More vasopressin, plus drinking too much water | Hyponatraemia, confusion and seizures |
Serotonergic effects | Risk of serotonin toxicity, especially with interacting drugs |
Sleep loss and the mood change that follows | Anxiety, tiredness and low mood after use |
Hot surroundings and sustained exertion raise the danger of hyperthermia.
Severe hyperthermia, seizures or reduced consciousness need urgent medical assessment. They are not simple anxiety.
Street products are unregulated and may contain other drugs or unpredictable doses. The tablet name a person reports does not tell you what they actually took.
Interactions
Monoamine oxidase inhibitors can make MDMA especially dangerous. MDMA increases monoamine release while the inhibitor blocks their breakdown.
Other serotonergic medicines and stimulants can increase harm and make toxicity harder to assess.
Taking another medicine to change MDMA's effects is not a reliable way to make it safe.
Reading the research on MDMA-assisted therapy
Trials of MDMA-assisted therapy combine controlled dosing with structured psychological treatment, screening and monitoring. Their results do not show that recreational use is therapeutic.
Points to weigh when you appraise these trials:
Expectancy and unblinding. The drug's strong subjective effects mean participants may recognise whether they had it. This complicates interpretation.
Beyond symptom scores. Also look at how long benefits last, at adverse effects, and at how far the findings generalise.
Licensing. Trial results alone do not mean a medicine is authorised or available in a given country.