MDMA (3,4-methylenedioxymethamphetamine) has a half-life of 6–9 hours and is detectable in urine for 2–4 days after occasional use. However, the more important timeline for most users is serotonin recovery: MDMA causes massive serotonin release followed by depletion, with full neurotransmitter recovery taking 2–4 weeks. This 'comedown' is the defining characteristic of MDMA's aftermath.
MDMA exhibits nonlinear pharmacokinetics — it inhibits its own metabolism via CYP2D6. This means small dose increases can produce disproportionately higher blood levels, making it particularly dangerous to 'stack' or redose.
The serotonin recovery timeline is critical health information. MDMA depletes serotonin stores and temporarily downregulates serotonin receptors. The 'comedown' typically peaks 2–3 days after use (hence 'suicide Tuesday') and gradually resolves over 1–4 weeks. Harm reduction guidelines recommend minimum 6–12 week intervals.
MDMA poses specific risks: serotonin syndrome (especially with SSRIs), hyperthermia (elevated body temperature), hyponatremia (dangerously low sodium from excessive water intake), and cardiovascular stress. These risks are significantly elevated by environmental factors like high ambient temperature and prolonged physical activity.
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.
The most common mistake is treating the result as a precise measurement rather than an evidence-based estimate. All body metric calculators have margins of error — use the result as a tracking baseline, not a clinical diagnosis.
A personal trainer uses the calculator with a new client to set a measurable starting point. Re-running the calculation at 4-week intervals provides an objective progress metric that supports motivation and programme adjustments.
MDMA Clearance & Recovery
Detection: ~5 × Half-life (6-9h) = 30-45h clearance. Serotonin Recovery: 2-4 weeks
While the drug clears the body within 2–3 days, serotonin recovery is the rate-limiting factor for full functional normalization.
Occasional user, single session, tested 3 days later.
Result: Urine test at day 3: borderline — may or may not test positive depending on sensitivity. Blood is likely clear. Serotonin recovery ongoing — mood fully normalizes in 2–3 weeks.
Occasional use: 2–4 days. Frequent use: 4–7 days. The primary metabolite (HMMA) is what specialized tests detect.
Typically 1–5 days for the acute phase ('suicide Tuesday' peaks day 2–3). Full mood normalization: 2–4 weeks as serotonin replenishes.
Not always. Standard 5-panel tests may detect MDMA as an amphetamine false positive. Expanded panels (10+ panel) specifically test for MDMA.
NO — combining MDMA with SSRIs or MAOIs risks serotonin syndrome, a potentially life-threatening condition. This combination should never occur.