MDMA: dosage

MDMA is most often ingested orally in tablets [1]. Oral ingestion produces effects with onset within 30 to 45 minutes [1], and the acute effects last 4 to 6 hours [1]. Some users report effects lasting longer than that [1].

There is no reliable dosing figure in the reference data behind this page — no threshold, no common range, no established ceiling. The practical response is the harm-reduction default: start with less than you're inclined to, wait out the full onset window before deciding you need more, and don't take a second dose to "boost" a first one that hasn't peaked yet.

What is documented is what goes wrong at the high end. High doses interfere with the body's ability to regulate its own temperature, producing hyperthermia [1], and can push on to liver, kidney, and cardiovascular failure, and death [1].

Content is a separate problem from amount. Tablets sold as MDMA may contain other substances such as methamphetamine, MDA, ketamine, caffeine, amphetamine, cathinones, synthetic cannabinoids, and/or opioids such as fentanyl [1]. Testing what you have, taking a small amount first, and never using alone are standard harm-reduction precautions given that uncertainty.

References

1. 3,4-Methylenedioxymethamphetamine (MDMA) — Drug Enforcement Administration (DEA) Diversion Control Division