MDMA, Measured — an evidence-graded harm-reduction reference

A short, strange history

Patented as a chemical intermediate, ignored for sixty years, rediscovered by a chemist, adopted by therapists, banned, then dragged back through fourteen years of clinical trials. The last chapter is still being written.

1912
Anton Köllisch at Merck synthesizes MDMA as an intermediate on the way to a styptic. The patent is filed in 1912 and granted in 1914. The long-repeated story that it was an appetite suppressant is a myth traced to the original documents.¹
1953–54
US Army chemical-warfare researchers test MDMA (as "EA‑1475") in animals at the University of Michigan. No human trials.¹
1976–78
Alexander Shulgin resynthesizes MDMA, tries it himself, and with David Nichols publishes the first human description: "an easily controlled altered state of consciousness with emotional and sensual overtones."²
1977–85
Psychotherapist Leo Zeff spreads MDMA ("Adam") to an estimated thousands of clinicians as a therapy adjunct. Greer and Tolbert publish the first clinical case series in 1986.³
1985
With recreational "Ecstasy" spreading through Dallas clubs, the DEA places MDMA in Schedule I on an emergency basis. An administrative law judge recommends Schedule III; the DEA overrules him. Grinspoon and Bakalar argue in 1986 for its therapeutic value.⁴
2002–03
A Science paper reports dopaminergic neurotoxicity in primates after ordinary doses. It is retracted a year later: the vials contained methamphetamine, not MDMA. The episode shaped a decade of public messaging.³⁶
2011
First randomized controlled trial of MDMA-assisted therapy for PTSD (n=20) is published by Mithoefer and colleagues, funded by MAPS.⁵
2017
FDA grants Breakthrough Therapy designation for MDMA-assisted therapy in PTSD.
2021–23
Two Phase 3 trials (MAPP1, MAPP2) report that roughly two-thirds to 71% of participants no longer meet PTSD criteria after three sessions, versus about a third to 48% with placebo plus the same therapy.^6,7
2023
Australia becomes the first country to allow authorised psychiatrists to prescribe MDMA for PTSD (July 2023).⁹
2024
An FDA advisory committee votes 9–2 that efficacy was not adequately shown, citing functional unblinding, durability, missing adverse-event capture and misconduct at one site. On August 9 the FDA issues a Complete Response Letter asking for another Phase 3 trial.⁸
2026
Lykos, restructured as Resilient Pharmaceuticals, resubmits the application in August 2026, leaning on VA long-term follow-up data, a new cardiac/QT safety study, and an audit of the original trials rather than a fresh Phase 3. The FDA's response is pending as of this writing.⁹

The compound

One molecule, many names, and a street supply that frequently isn't it.

Identity

IUPAC: (RS)-1-(1,3-benzodioxol-5-yl)-N-methylpropan-2-amine
Formula: C₁₁H₁₅NO₂ · MW 193.25 (free base), 229.7 (hydrochloride salt)
Class: substituted amphetamine (phenethylamine); the methylenedioxy ring is what turns a stimulant into an "entactogen"²
Stereochemistry: one chiral centre. S(+)-MDMA is the more potent monoamine releaser and stimulant; R(−)-MDMA is more serotonergic/psychedelic-leaning and longer-acting. Everything on the street and in trials is the 50:50 racemate.¹⁴
Other names: midomafetamine (INN, used in the FDA filings), Ecstasy/E/X (pressed tablets), Molly/Mandy (crystal or capsule powder), Adam (1970s therapy circles)

Relatives worth knowing

MDA — MDMA's N-demethylated metabolite and a drug in its own right ("Sass"); more psychedelic, more stimulating, longer, with a narrower margin.
MDEA, MBDB — close analogues from the 1980s–90s, now rare.
Methylone, MDPV, α-PVP ("bath salts") — synthetic cathinones that have repeatedly been sold as Molly. Hair testing of US nightlife attendees found many people who denied bath-salt use tested positive for them.⁴¹
PMA / PMMA — slower onset, lower euphoria, far more hyperthermic and serotonergic toxicity. Sold as "Ecstasy" they have caused clusters of deaths; the slow onset invites redosing, which is what kills.³²
2C-B, methamphetamine, ketamine, caffeine — common tablet adulterants across drug-checking programs.

Why drug checking matters more than any supplement. The single highest-yield harm-reduction act is confirming that a substance is MDMA and not something worse. Reagent kits (Marquis, Mecke, Simon's) can show whether MDMA-family compounds are present and flag the usual substitutes; fentanyl test strips cover the opioid contamination risk; laboratory services (in the US, DrugsData / DanceSafe) can quantify what a reagent cannot. A reagent can't tell you the dose, and pressed tablets in recent European checking data have ranged widely in content, sometimes exceeding 200 mg.

Mechanism of action

MDMA is not a classic psychedelic. It is a releaser: it walks into the neuron through the monoamine transporters and pushes serotonin, norepinephrine and dopamine out.

1. Release, not just reuptake blockade

MDMA is a substrate for SERT, NET and DAT. It enters the terminal, disrupts vesicular storage (VMAT2) and reverses transporter direction, dumping stored monoamine into the synapse. Potency is roughly serotonin ≈ norepinephrine > dopamine, which is what separates it pharmacologically from methamphetamine.¹³

The proof is pharmacological: pre-treating people with an SSRI (citalopram, paroxetine) blunts most of MDMA's subjective and cardiovascular effects, because the SSRI blocks the door MDMA uses.^15,16

2. The neuroendocrine cascade

Serotonin release drives oxytocin, cortisol, prolactin and vasopressin (AVP) secretion. Oxytocin appears to carry the prosocial, affiliative signature: in rodents the effect is blocked by oxytocin-receptor antagonists and depends on 5-HT_1A receptors; in humans plasma oxytocin rises and correlates with feelings of closeness.¹⁷ The AVP rise is why water handling goes wrong (see hyponatremia).²⁷

3. Why it might work for trauma

Imaging shows reduced amygdala reactivity to threatening faces and increased ventral striatal response to positive stimuli.¹⁹ In mice MDMA enhances fear-extinction learning²¹ and reopens a "critical period" for social reward learning via oxytocin signalling in the nucleus accumbens, an effect that outlasts the drug by weeks.²⁰ MDMA also promotes dendritic growth (neuritogenesis) in cultured neurons, in line with classic psychedelics.²²

Receptor-level footnotes

Weak direct agonism at 5-HT_2A; the mild perceptual shimmer is mostly indirect via released serotonin. Ketanserin (a 5-HT_2A antagonist) reduces perceptual but not emotional effects.
α₂-adrenergic and TAAR1 activity modulate the sympathetic drive; noradrenaline release, not dopamine, best explains the cardiovascular and much of the stimulant effect in human blockade studies.²³
MDA, the active metabolite, contributes and accumulates with repeated dosing.¹¹

The six-factor experience

A factor analysis of user reports identified six components: perceptual alteration, entactogenesis ("I can deliberately generate insights about myself and my relationships"), prosocial warmth, aesthetic/mood effects, negative intoxication (memory, confusion), and altered sexual experience. Controlled-lab studies replicate the middle four robustly and find the first is mild at therapeutic doses.²⁴

Pharmacokinetics

The most important fact about MDMA kinetics is that they are non-linear. The drug inhibits the enzyme that clears it, so a little more in produces a lot more exposure.

Absorption

Oral bioavailability is high. Detectable in plasma within ~20–30 minutes; time to peak concentration (t_max) about 1.5–2.5 h, later on a full stomach.¹² Subjective onset is 30–60 min; the peak effect window is about 1.5–3 h.²⁵

Metabolism

Two paths. O-demethylenation (CYP2D6, with CYP3A4/1A2) opens the methylenedioxy ring to HHMA, which COMT converts to HMMA. N-demethylation (CYP2B6/1A2/3A4) makes MDA. Only ~10–20% is excreted unchanged.¹¹ Crucially, the ring-opening step forms a metabolite complex that inactivates CYP2D6 for hours (mechanism-based inhibition), which is why clearance slows within a single session.¹⁰

Elimination

Terminal half-life about 8–9 h (MDA ~15 h). Ten hours after a dose, roughly half is still on board; it is not effectively gone for 24–36 h.¹² Sleep is measurably impaired that night even after effects fade.²³

The non-linearity, in numbers

In controlled studies, raising the dose from 100 to 150 mg (a 50% increase) raised peak plasma concentration and total exposure by well over 50%.¹⁰ When a second 100 mg dose was given 2 h after the first, plasma levels and cardiovascular effects rose disproportionately, and effects were prolonged more than they were intensified.²⁶ Clinical trials used a supplemental half-dose at 1.5–2 h for exactly this reason: it extends the plateau with a smaller step in exposure than a full repeat would.⁶

Who clears it slowly

CYP2D6 poor metabolizers (~5–10% of Europeans) show higher levels and stronger cardiovascular effects, though because MDMA inhibits its own clearance in everyone, the genotype gap is smaller than once feared.⁴⁰
CYP2D6 inhibitors taken alongside (paroxetine, fluoxetine, bupropion, ritonavir, quinidine) raise MDMA levels; ritonavir has caused a fatality.^16,31,38
Women report stronger subjective and adverse effects than men at the same mg/kg, and dominate the hyponatremia case series.^24,28

Session timeline explorer

Enter a start time and see the published time-course laid over a clock: when effects begin, peak and fade, when the body is under the most strain, and how far into tomorrow the tail reaches. Built from controlled single-dose studies at 75–125 mg oral; individual variation is wide.^12,23,25

Time the dose is taken Assumed food state Show the research on a second dose at ~2 h Show strain windows

Compare what the controlled studies actually gave (overlays, relative scale):

Curves are relative subjective intensity and relative plasma level, not milligrams. The amber line marks the intensity above which controlled studies most often recorded jaw tension, tachycardia, raised blood pressure and temperature.

Nothing plotted yetPick a start time above, or load the example.

Where the strain sits, hour by hour

Heart rate & blood pressurePeak +1 to +3 h

Mean rises of ~20–30 bpm and ~20–30 mmHg systolic at 125 mg; comparable to brisk exercise in healthy people, dangerous with heart disease or stimulant co-use.^23,25

Jaw tension, bruxism+1 to +5 h

Reported by the majority at 125 mg; the most common physical complaint in trials.²³

Body temperature+2 to +4 h

Rises ~0.3–0.8 °C in a quiet lab. In a hot room with dancing, sympathetic drive plus impaired heat loss is the hyperthermia pathway.⁴⁴

Water handling (AVP)+1 to +4 h

Vasopressin peaks, thirst and dry mouth push fluid intake, kidneys hold water: the hyponatremia set-up, worst in women.^27,43

Nausea, appetite loss+0.5 to +3 h

Common at onset; appetite suppression lasts into the next day.²³

Sleep+6 to +12 h

Insomnia and reduced sleep quality that night even in the lab; the strongest predictor of feeling bad the next day.²³

Mood dip+24 to +72 h

Low mood and irritability are real but, in controlled studies with pure MDMA and normal sleep, far milder than the "suicide Tuesday" folklore. Heavier and more frequent use makes it worse.^23,42

Effects and adverse effects, by dose

Pooled data from placebo-controlled studies in healthy volunteers, mostly Liechti's group in Basel, and safety data from the PTSD trials. Doses are what researchers gave, reported as findings, not as a recommendation.

Dose studied (oral)	What was observed	Source
20–30 mg	Threshold / active placebo. Used as the low-dose comparator in the Phase 2 PTSD trials because it produces just enough to be felt (mild alertness, slight warmth) without the entactogenic effect. Little cardiovascular change.	5, 47
40–60 mg	Light. Noticeable warmth and mood lift for most, well short of a full effect; the 40 mg arm in Phase 2 already separated from 25 mg on some measures. Cardiovascular change small. Where "less than you think" lands.	47
75 mg	Clear entactogenic effects in most people; well tolerated. Bruxism, restlessness and sweating in a minority. Heart rate up ~10–20 bpm. In the veterans trial 75 mg produced the largest PTSD improvement of the three arms.	23
80–120 mg (+ optional 40–60 mg at 1.5–2.5 h)	The regimen used in the Phase 2/3 PTSD trials (up to 180 mg total). Adverse events in >10% of sessions: muscle tightness, decreased appetite, nausea, hyperhidrosis, feeling cold, restlessness, headache, jaw clenching, nystagmus. Transient BP/HR rises; no serious cardiovascular events; no unexpected serious adverse reactions across >1,500 research exposures.	6, 7
125 mg	Full effects; adverse effects clearly more frequent and intense than at 75 mg: bruxism, lack of appetite, impaired concentration, tachycardia (mean ~+25–30 bpm), SBP rise ~+25–30 mmHg, temperature +0.4–0.8 °C. Higher rates in women.	23, 24
150 mg / 100 + 100 mg repeated	Disproportionate rise in plasma levels and cardiovascular effects; prolonged duration without proportional gain in euphoria; the ceiling of what has been given under monitoring.	10, 26
Above ~200 mg, stacked doses, pills of unknown content	Where the emergency and forensic literature lives: hyperthermia, hyponatremia, serotonin toxicity, arrhythmia, rhabdomyolysis, hepatic injury, DIC. Total dose, ambient heat, co-ingestants and redosing are the recurring factors, not a single "toxic dose".	29

How adverse-effect frequency scales

Bruxism

Tachycardia >100

Poor concentration

Nausea

Anxiety at onset

Bar length is a qualitative ranking of how strongly each effect increased from 75 to 125 mg in pooled controlled data; green-to-red encodes the dose gradient, not a probability.²³

Body weight, sex and the mg/kg question

Trials dose by fixed milligrams, not weight, and outcomes do not track weight strongly. Sex is a bigger modifier: at the same mg/kg women reported more intense psychological effects and more adverse effects than men, while men showed larger blood-pressure rises.²⁴ The commonly repeated "1.5 mg/kg" rule of thumb comes from those same lab studies (1.0–1.7 mg/kg ranges), which is a description of what was tested, not a safety guarantee. Harm-reduction organizations (DanceSafe, RollSafe) publish their own guidance on amounts.

Serious risks and what to do

Deaths from MDMA are rare relative to use, and they cluster around four mechanisms. Each has early signs and a specific response.

Hyperthermia

The dominant cause of MDMA deaths. Serotonergic and noradrenergic drive raise heat production, cutaneous vasoconstriction blocks heat loss, and a hot crowded room plus hours of dancing finishes it.^29,44 In rats, the same dose that is neurotoxic at a warm ambient temperature is harmless in a cool room, which is why cooling is the intervention with the best mechanistic backing.³⁰

Signs: hot skin, confusion or agitation out of proportion, no longer sweating, rigid muscles, temperature over 40 °C. Do: stop dancing, get to cool air, remove layers, cool water on skin and fans, sip electrolyte fluid, call emergency services. Rapid cooling in hospital is life-saving; delay is what kills.

Hyponatremia (water intoxication)

MDMA raises vasopressin so the kidneys retain water; users, told to "stay hydrated", drink litres. Serum sodium falls, the brain swells. Cases are overwhelmingly women, whose brains have less room to compensate.^27,28,43

Signs: headache, nausea and vomiting, confusion, drowsiness, then seizures, several hours in. Do: treat as an emergency; do not give more water. Prevention is the point: total fluid around 250 mL/h at rest and up to 500 mL/h dancing, preferably with electrolytes, and salty snacks. Sipping, not chugging.

Serotonin toxicity

Rare with MDMA alone at ordinary doses; the classic trigger is combination with an MAOI (including moclobemide, the harmala alkaloids in ayahuasca, and the antibiotic linezolid), or stacked doses. Tramadol, DXM, lithium and high-dose SSRIs add risk.²⁹

Signs: clonus and hyperreflexia, tremor, sweating, agitation, fever, diarrhoea, racing heart. Do: emergency care; cyproheptadine and cooling in hospital.

Cardiovascular and other

Arrhythmia and hypertensive events in people with structural heart disease, long QT or with stimulant co-use. Hepatotoxicity, sometimes delayed by days, is idiosyncratic and can follow hyperthermia. Rhabdomyolysis and disseminated coagulation are downstream of heat.²⁹ Panic and, rarely, psychosis in the vulnerable. Trial exclusion criteria are a useful risk map: uncontrolled hypertension, arrhythmia, QTc >450 ms, family history of sudden cardiac death, psychosis, bipolar I.⁶

Getting help. In the US call 911; most states have Good Samaritan laws that protect the caller and the patient from possession charges when seeking help for an overdose. Poison Control (1‑800‑222‑1222) will talk you through it without judgement. Tell responders exactly what was taken and when. Never leave a confused or overheated person alone to "sleep it off".

Interactions

Most of the human interaction data comes from controlled pretreatment studies. The pattern: things that raise MDMA levels are dangerous, things that block its transporter are disappointing, and things that add serotonin or heat are both.

Combination	Risk	What is known
MAOIs (phenelzine, tranylcypromine, moclobemide, selegiline, ayahuasca/harmalas, linezolid, methylene blue)	Avoid	Severe serotonin toxicity and hypertensive crisis; documented deaths. Weeks of washout needed.²⁹
Ritonavir / cobicistat (HIV boosters), strong CYP2D6 inhibitors	Avoid	Fatal case at an ordinary MDMA dose with ritonavir; MDMA levels multiply.³¹
PMA/PMMA, stimulants (amphetamine, cocaine, cathinones)	Avoid	Additive hyperthermia and cardiovascular load; PMA is the deadliest "Ecstasy" substitute.³²
Tramadol, DXM, lithium, pethidine	Avoid	Serotonergic and seizure-threshold risk; case reports of serotonin syndrome.²⁹
SSRIs / SNRIs (paroxetine, fluoxetine, sertraline, duloxetine, citalopram)	Blunts, and complicates	Pretreatment sharply reduces subjective and cardiovascular effects; paroxetine also raises MDMA plasma levels ~30% via CYP2D6.^15,16 The practical hazard is people taking more to compensate. Trials required 5 half-lives off.
Bupropion	Caution	Raises MDMA concentrations and prolongs effects while slightly lowering heart rate; more exposure, longer night.³⁸
Alcohol	Caution	MDMA masks sedation while alcohol worsens dehydration and heat handling; blood MDMA rises modestly, alcohol effects on driving are not offset.³⁹
Cannabis	Mixed	Widely combined; increases confusion and anxiety in some, may slightly lower body temperature in animal work; no clear human toxicity signal.
Ketamine, GHB, benzodiazepines	Caution	GHB and MDMA is a well-documented ED presentation (respiratory depression masked by stimulation). Ketamine adds dissociation and falls. Benzodiazepines are what hospitals give for agitation and are not themselves a serotonergic risk.
Classic psychedelics (LSD, psilocybin; "candy-flipping")	Caution	Additive serotonergic and cardiovascular load; unpredictable intensity. No controlled human data.
Caffeine, nicotine	Minor	Additive heart-rate and heat load; trials asked participants to avoid both for 2 h before and 6 h after.
5-HTP, St John's wort, tryptophan	Theoretical	Serotonin precursor/enhancer plus a releaser; no human study, and most guides advise a 24-h gap on mechanistic grounds.

Harm reduction by supplementation: what's proven, what isn't

The internet's MDMA supplement stacks are built on real papers. Almost all of those papers are in rats given neurotoxic regimens (typically 5–20 mg/kg, repeated, in warm rooms). Not one supplement has been tested in a human MDMA trial for neuroprotection. Here is each claim graded by the best evidence behind it.

A Human controlled evidence B Human mechanistic or observational support C Animal data only D Anecdote / theory ✕ Evidence of harm or hazard

Intervention	Grade	The claim	What the evidence actually shows
Keeping cool, taking breaks	A/B	Prevents hyperthermia and (in animals) neurotoxicity	Ambient temperature is the strongest modifier of both toxicity and serotonergic damage in animal models; hyperthermia is the leading mechanism of human deaths. Cheapest and best-supported intervention on this page.^30,44
Measured fluids with electrolytes	B	Prevents hyponatremia	Human data: MDMA impairs the response to a water load and lowers serum sodium; case series link overdrinking to fatal hyponatremia. Moderate sodium-containing fluids and salty food address the mechanism directly. No RCT, but the physiology is human and unambiguous.^27,28
Drug checking	B	Avoids adulterants and mis-sold substances	Observational: substitution with cathinones, PMA/PMMA and fentanyl is documented; drug-checking services demonstrably change users' decisions. Not a supplement, but the highest-yield item here.^32,41
Alpha-lipoic acid (ALA)	C	Neuroprotection	One rat study: 100 mg/kg i.p. twice daily for two days before a neurotoxic MDMA dose prevented serotonergic deficits, without preventing hyperthermia. Equivalent human dosing would be grams, injected. No human data.³³
Acetyl-L-carnitine (ALCAR)	C	Mitochondrial neuroprotection	Adolescent rats, high-dose MDMA: pretreatment reduced mitochondrial damage and serotonin depletion. No human data.³⁴
Vitamin C (ascorbate)	C	Scavenges free radicals	Rat study: reduced hydroxyl-radical formation and serotonin depletion after a neurotoxic regimen. No human data; harmless at ordinary doses, GI upset above ~2 g.³⁵
Vitamin E, CoQ10, nicotinamide, NAC, ginger, melatonin, green tea (EGCG)	C	Antioxidant neuroprotection	Rodent or in-vitro antioxidant data of varying quality; melatonin and ginger evidence is thinnest. None tested in humans with MDMA. The shared caveat: rodent neurotoxic regimens deplete serotonin axons in a way that has not been convincingly demonstrated in humans at single therapeutic-range doses.^37,45
Magnesium	D	Reduces jaw clenching	Purely anecdotal. Bruxism from MDMA is central (serotonergic/dopaminergic), not a magnesium-deficiency state; no trial exists. Low risk: glycinate/citrate forms cause less diarrhoea than oxide. Chewing gum protects teeth; it does not stop the clenching.
5-HTP after the session	D	Speeds serotonin recovery, softens the come-down	Plausible biochemistry, no human MDMA trial. One small study found tryptophan supplementation modestly helped memory performance in ex-users. Taking it during or within 24 h is a theoretical serotonin-toxicity hazard.⁴⁶
Antioxidants "to prevent losing the magic"	D	Prevents tolerance	One rodent study found vitamin C reduced MDMA tolerance. "Losing the magic" in humans tracks frequency and cumulative dose; the only intervention with support is spacing sessions out.^35,42
Pre-loading with an SSRI, or taking one "for the come-down"	✕	Protects serotonin neurons	SSRIs do block MDMA's entry into serotonin terminals (which is the rodent neuroprotection rationale), but in humans that means blunted effects, higher MDMA levels, and pressure to redose. Fluoxetine's long half-life makes "after" also "during".^15,16
Unlimited water	✕	"Stay hydrated"	The advice that produced a generation of hyponatremia cases. Fluids are for replacing sweat, not for flushing the drug.²⁸

The honest summary

If you rank interventions by evidence quality, the top four are: confirm the substance, keep the body cool, drink measured electrolyte fluids, and take less rather than more, less often. The supplement stack sits below all of them, is unlikely to hurt at labelled doses, and should never be the reason someone feels safe enough to take a larger or repeated dose.

Is MDMA neurotoxic in humans?

Heavy, frequent users show reduced serotonin-transporter binding on PET that partially recovers with abstinence,⁴⁵ and some cognitive differences that are confounded by polydrug use and sleep. A study designed to strip out those confounds found no significant cognitive deficits in moderate users.³⁷ Clinical-trial participants given 2–3 monitored doses show no signal of harm on cognitive testing.⁶ The honest position: dose- and frequency-dependent serotonergic changes are real at the heavy end; single, spaced, moderate doses have not been shown to cause lasting damage; nobody has proven that any pill prevents either.

Frequency, tolerance and the come-down

Spacing

Clinical trials dosed roughly once a month, three times, with no evidence of tolerance across sessions.⁶ Harm-reduction organizations commonly suggest at least a three-month gap, a heuristic drawn from serotonin-transporter recovery timelines rather than a trial. Weekly use is where the transporter-imaging, mood and "lost magic" data concentrate.^42,45

Tolerance

Acute tolerance is immediate: serotonin stores are depleted within the session, which is why a late redose gives stimulation and side effects without the warmth. Cross-session tolerance builds with frequency and is slow to reverse.²⁶

The days after

Sleep loss, exertion, alcohol and dehydration explain more of the next-day slump than serotonin depletion does in controlled comparisons. Protecting sleep that night (a dark, cool room; no more stimulants) is the only after-care with a human mechanism behind it. Persistent low mood beyond a week, or any mood crash in someone with a depression history, is a reason to talk to a clinician.²³

A note on the therapeutic context

In the PTSD trials, MDMA was given two or three times, months apart, at 80–120 mg with an optional half-dose supplement, after fasting, with vital-sign monitoring, in a controlled-temperature room, with two therapists present for 8 hours and an overnight stay. The safety record from that setting (no unexpected serious adverse reactions across thousands of exposures) is a statement about that setting.^6,7 Almost every factor in the emergency literature (heat, exertion, unknown dose, stacked doses, co-ingestants, no observer) is the inverse of it. That gap is what "harm reduction" is trying to close.

References

Each entry links to a PubMed search for the paper so it resolves even if a DOI changes.

Freudenmann RW, Öxler F, Bernschneider-Reif S. The origin of MDMA (ecstasy) revisited: the true story reconstructed from the original documents. Addiction. 2006;101:1241–5. PubMed
Shulgin AT, Nichols DE. Characterization of three new psychotomimetics. In: Stillman RC, Willette RE, eds. The Psychopharmacology of Hallucinogens. Pergamon; 1978. See also Shulgin A, Shulgin A. PiHKAL. Transform Press; 1991.
Greer G, Tolbert R. Subjective reports of the effects of MDMA in a clinical setting. J Psychoactive Drugs. 1986;18:319–27. PubMed
Grinspoon L, Bakalar JB. Can drugs be used to enhance the psychotherapeutic process? Am J Psychother. 1986;40:393–404. PubMed
Mithoefer MC, et al. The safety and efficacy of ±3,4-methylenedioxymethamphetamine-assisted psychotherapy in subjects with chronic, treatment-resistant PTSD: the first randomized controlled pilot study. J Psychopharmacol. 2011;25:439–52. PubMed
Mitchell JM, et al. MDMA-assisted therapy for severe PTSD: a randomized, double-blind, placebo-controlled phase 3 study. Nat Med. 2021;27:1025–33. PubMed
Mitchell JM, et al. MDMA-assisted therapy for moderate to severe PTSD: a randomized, placebo-controlled phase 3 trial. Nat Med. 2023;29:2473–80. PubMed
US FDA Complete Response Letter to Lykos Therapeutics, 9 Aug 2024 (released publicly Sept 2026); Psychopharmacologic Drugs Advisory Committee, 4 June 2024. Coverage: Psychiatric Times.
Regulatory status summary including Australia's July 2023 authorised-prescriber scheme and the August 2026 Resilient Pharmaceuticals resubmission: mindmedicinelaw.com/guides/mdma; Lykos restructuring: AJMC.
de la Torre R, et al. Non-linear pharmacokinetics of MDMA ('ecstasy') in humans. Br J Clin Pharmacol. 2000;49:104–9. PubMed
de la Torre R, Farré M, Roset PN, et al. Human pharmacology of MDMA: pharmacokinetics, metabolism, and disposition. Ther Drug Monit. 2004;26:137–44. PubMed
Kolbrich EA, et al. Plasma pharmacokinetics of 3,4-methylenedioxymethamphetamine and its metabolites after controlled oral administration to young adults. Ther Drug Monit. 2008;30:320–32. PubMed
Simmler LD, et al. Pharmacological characterization of designer cathinones in vitro. Br J Pharmacol. 2013;168:458–70 (includes MDMA transporter profile). PubMed
Pitts EG, et al. (±)-MDMA and its enantiomers: potential therapeutic advantages of R(−)-MDMA. Psychopharmacology. 2018;235:377–92. PubMed
Liechti ME, Baumann C, Gamma A, Vollenweider FX. Acute psychological effects of MDMA are attenuated by the serotonin uptake inhibitor citalopram. Neuropsychopharmacology. 2000;22:513–21. PubMed
Farré M, et al. Pharmacological interaction between MDMA and paroxetine: pharmacological effects and pharmacokinetics. J Pharmacol Exp Ther. 2007;323:954–62. PubMed
Thompson MR, et al. A role for oxytocin and 5-HT1A receptors in the prosocial effects of MDMA in rats. Neuroscience. 2007;146:509–14; Dumont GJ, et al. Increased oxytocin concentrations and prosocial feelings in humans after ecstasy administration. Soc Neurosci. 2009;4:359–66. PubMed
Bedi G, Phan KL, Angstadt M, de Wit H. Effects of MDMA on sociability and neural response to social threat and social reward. Psychopharmacology. 2009;207:73–83. PubMed
Nardou R, et al. Oxytocin-dependent reopening of a social reward learning critical period with MDMA. Nature. 2019;569:116–20. PubMed
Young MB, Andero R, Ressler KJ, Howell LL. 3,4-Methylenedioxymethamphetamine facilitates fear extinction learning. Transl Psychiatry. 2015;5:e634. PubMed
Ly C, et al. Psychedelics promote structural and functional neural plasticity. Cell Rep. 2018;23:3170–82. PubMed
Vizeli P, Liechti ME. Safety pharmacology of acute MDMA administration in healthy subjects. J Psychopharmacol. 2017;31:576–88. PubMed
Liechti ME, Gamma A, Vollenweider FX. Gender differences in the subjective effects of MDMA. Psychopharmacology. 2001;154:161–8; Sumnall HR, Cole JC, Jerome L. The varieties of ecstatic experience. J Psychopharmacol. 2006;20:670–82. PubMed
Mas M, et al. Cardiovascular and neuroendocrine effects and pharmacokinetics of MDMA in humans. J Pharmacol Exp Ther. 1999;290:136–45. PubMed
Peiró AM, et al. Human pharmacology of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) after repeated doses taken 2 h apart. Psychopharmacology. 2013;225:883–93. PubMed
Baggott MJ, et al. MDMA impairs response to water intake in healthy volunteers. Adv Pharmacol Sci. 2016;2016:2175896. PMC
Rosenson J, et al. Patterns of ecstasy-associated hyponatremia in California. Ann Emerg Med. 2007;49:164–71. PubMed
Hall AP, Henry JA. Acute toxic effects of 'Ecstasy' (MDMA) and related compounds: overview of pathophysiology and clinical management. Br J Anaesth. 2006;96:678–85. PubMed
Malberg JE, Seiden LS. Small changes in ambient temperature cause large changes in MDMA-induced serotonin neurotoxicity and core body temperature in the rat. J Neurosci. 1998;18:5086–94. PubMed
Henry JA, Hill IR. Fatal interaction between ritonavir and MDMA. Lancet. 1998;352:1751–2. PubMed
Vevelstad M, et al. The PMMA epidemic in Norway: comparison of fatal and non-fatal intoxications. Forensic Sci Int. 2012;219:151–7. PubMed
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Human evidence for post-session serotonin precursors is limited to small, uncontrolled reports of tryptophan or 5-HTP supplementation in former ecstasy users; no controlled MDMA trial exists. PubMed search

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