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The MDMA comedown is primarily a serotonin depletion phenomenon. MDMA triggers massive release of stored serotonin during use, leaving the brain temporarily depleted afterward. The comedown typically begins 12–24 hours after use, peaks around day 2–3 (earning it the nickname 'Suicide Tuesday' in party culture), and gradually resolves over 5–14 days as serotonin levels rebuild.
The comedown follows a characteristic arc. Day 1: 'Afterglow' — many users feel residual warmth and connection, sometimes mistaken for having avoided a comedown. Day 2–3: Serotonin depletion peaks — low mood, irritability, anxiety, poor sleep quality, and reduced motivation. Day 4–5: Gradual improvement. Day 7–14: Most users report return to baseline mood.
The neurochemistry behind the comedown is well-documented. MDMA causes serotonin vesicles to reverse their transport direction, dumping stored serotonin into the synaptic cleft. After the drug clears, vesicles need to resynthesize serotonin from tryptophan — a process requiring tryptophan hydroxylase, which MDMA temporarily deactivates. Full enzyme recovery takes approximately 2 weeks.
Comedown severity correlates with several factors: total dose (higher = worse), environmental heat (hot venues worsen neurotoxicity), hydration (dehydration amplifies serotonin depletion), combination with other substances (alcohol notably worsens comedowns), and baseline serotonin status. Individuals already low in serotonin (e.g., those with depression) often experience more severe comedowns.
Use this calculator as a starting point for any health or fitness goal that requires a numeric benchmark. The result is an estimate, not a diagnosis — but it provides a concrete figure to track against over time.
Many users apply adult health classifications to children and teenagers, which is incorrect. Paediatric norms for height, weight, BMI, and body composition are age-and-sex-specific. Use age-appropriate reference tools for anyone under 18.
A nurse calculates a patient's health metric during a routine assessment, then uses the result alongside other clinical indicators to contextualise the finding — correctly treating the number as one data point among several rather than a standalone answer.
MDMA use typically occurs on weekends. By Tuesday (day 2–3), serotonin depletion is at its worst, causing significant mood drops. The name is colloquial — actual suicidal ideation should be taken seriously and warrants professional help.
Some users report benefit from 5-HTP (a serotonin precursor), but it should NOT be taken within 24 hours of MDMA use due to theoretical serotonin syndrome risk. Evidence for its effectiveness is anecdotal, not clinical.
Harm reduction guidelines suggest minimum 6–12 week intervals. More frequent use leads to worse comedowns, diminished effects, and potential neurotoxicity. There is no guaranteed 'safe' frequency.
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