3-MMC

3-Methylmethcathinone

Metaphedrone, 3M, meow, mcat, 3-meph

Psychoactive Class

Chemical Class

3-MMC is a synthetic stimulant-entactogen of the substituted cathinone class.¹ It is a structural isomer of mephedrone (4-MMC) and first appeared in Sweden in 2012 as a designer drug alternative following mephedrone's widespread prohibition. It quickly gained presence on the online research chemical market and has frequently been marketed as a mephedrone substitute. Insufflation of this substance is reported to be notably painful.

Dosage & Duration

Dosage

Threshold~25 mg

Light25-75 mg

Moderate75-150 mg

Strong150-300 mg

Heavy300+ mg

Bioavailability

~7%

Duration

Onset10-30 minutes

Come Up30-60 minutes

Peak2-3 hours

Offset1-1.5 hours

After Effects2-4 hours

Total4-6 hours

Half-life

~50 minutes

Subjective Effects

Effects vary widely by individual, dose, and context.

Forked from Subjective Effect Documentation work

by Josie KinsAugust 2016.

Reagent Testing

Loading reagent data

Expected colorimetric results are being prepared.

Pharmacology

Pharmacodynamics

3-MMC acts as a monoamine transporter substrate that potently releases dopamine and norepinephrine and inhibits their reuptake at the respective transporters.² It displays moderate serotonin releasing activity, with greater selectivity for dopamine and especially norepinephrine over serotonin as a releasing agent.² 3-MMC binds to serotonin 5-HT1A, 5-HT2A, and 5-HT2C receptors and adrenergic α1A and α2A receptors, with substantially stronger affinity at the adrenergic sites.² It lacks agonist activity at the 5-HT2A receptor and is inactive at rat and human TAAR1.³²

Pharmacokinetics

The oral bioavailability of 3-MMC has been estimated at approximately 7% in a pig study, with peak blood concentrations attained within 5 to 10 minutes and an elimination half-life of roughly 50 minutes.⁴ Plasma concentrations fell below the limit of detection 24 hours after oral ingestion.⁴ The metabolic pathway is not well characterized but is thought to involve β-keto-reduction followed by N-demethylation.⁵

Interactions

Dangerous

Highest risk

These combinations are considered extremely harmful and should always be avoided. Reactions to these drugs taken in combination are highly unpredictable and have a potential to cause death.

5-HTPAlcoholDXMDissociativesMAOIsMDMAMXENBOMe compoundsSNRIsSSRIsSerotonin releasersStimulantsTramadol

TripSit

Tolerance

Full Tolerance

Repeated 3-MMC use over time can produce tolerance across many effects, leading users to need larger doses for similar results. The compound's strong compulsive-redosing potential can speed tolerance development during prolonged sessions.

Baseline Reset

1-2 weeks

Half Tolerance

3-7 days

Cross Tolerance

Dopaminergic stimulants

Harm Potential

Addiction & Dependence

Psychological

High

3-MMC is described as extremely addictive with a high potential for abuse, reportedly more so than mephedrone.¹ Its short-lived euphoric rush combined with dopaminergic effects produces intense compulsive redosing, with users commonly consuming 0.5-2 grams in multi-hour sessions despite intending smaller doses.⁶

Physical

Moderate

Physical dependence can develop with chronic use. Cravings and withdrawal effects may occur upon sudden cessation, though specific withdrawal symptoms are not well-characterized in the literature.¹

Toxicity

Cardiovascular

Preliminary evidence suggests chronic high-dose use may carry cardiotoxic risks; acute effects include increased heart rate, elevated blood pressure, abnormal heartbeat, and vasoconstriction that can limit blood flow to organs.⁷ Heart valve issues have also been suggested but remain poorly characterized.

Central Nervous System

Preliminary evidence suggests chronic high-dose use may carry neurotoxic risks; symptoms of serotonin depletion are reported with overuse, manifesting as depression, cognitive fatigue, and motivation suppression during comedown periods.⁶

Musculoskeletal

Rhabdomyolysis has been reported as a serious adverse effect,¹ typically in cases involving hyperthermia and physical exertion.

Psychosis Risk

Delirium and confusion can occur at high doses, particularly when combined with temperature dysregulation, overheating, and inability to rest or rehydrate.¹ Risk of delusions and mania may be elevated when combined with dissociatives.

Seizure Risk

Seizures are a rare but documented adverse effect,¹ more likely in predisposed individuals or when taking heavy doses while dehydrated, undernourished, overheated, or fatigued.

History & Culture

Discovery and Emergence

3-MMC was first encountered in Sweden in 2012,⁸ emerging on the online research chemical market shortly after the banning of mephedrone in numerous countries.¹ It was created as a designer drug specifically chosen to mimic and…

Legality

International

UN Convention on Psychotropic Substances 1971 (Schedule II, placed March 2023)¹⁴

By Country

United StatesSchedule I

Illegal as a positional isomer of the controlled substance mephedrone. Explicitly designated as a controlled substance on December 13, 2023, and categorized by the DEA as a Schedule I positional isomer.¹⁸

BrazilIllegal

Listed on Portaria SVS/MS nº 344. Possession, production, and sale are prohibited under this regulation.

Czech RepublicIllegal

Banned substance under national drug control legislation.

IndiaNarcotic

Designated as a narcotic substance on February 8, 2024, making possession, production, and distribution illegal.

PolandII-P Category Drug

Classified as a II-P category controlled substance since April 25, 2024, making possession, production, and distribution illegal.

SwitzerlandControlled (Verzeichnis E)

Regulated as a defined derivative of cathinone under Verzeichnis E point 1. Use is permitted for legitimate scientific or industrial purposes only.

United KingdomClass B

Controlled as a Class B substance under the Misuse of Drugs Act 1971 through the cathinone catch-all clause, which covers structurally related compounds.

AustriaIllegal (NPSG)

Prohibited under the Neue-Psychoaktive-Substanzen-Gesetz (New Psychoactive Substances Act). Possession, production, and sale are illegal.

ChinaControlled

Banned since October 2015 along with numerous other synthetic compounds. This ban significantly impacted global availability as Chinese chemical companies were primary manufacturers.

GermanyAnlage I BtMG

Controlled under Anlage I of the Betäubungsmittelgesetz (Narcotics Act, Schedule I) since December 13, 2014.¹⁵ Manufacturing, possession, import, export, purchase, sale, procurement, and dispensing without license are prohibited.

NetherlandsList I (Opiumwet)

Initially classified as a List II (soft drug) substance effective October 28, 2021.¹⁶ Subsequently reclassified to List I (hard drug) in April 2024,¹⁷ carrying more severe penalties for possession and distribution.

SwedenNarcotic

Classified as a narcotic substance under Swedish drug control legislation.

TurkeyIllegal

Classified as a controlled drug. Possession, production, supply, and importation are prohibited.

References

Source Pages

Citations

Suggest an edit

Spotted a mistake, an outdated claim, or something missing from the 3-MMC article? Send the editors a private note. Feedback lands in a moderation queue and is never shown on the site.

3-MMC

3-Methylmethcathinone

Metaphedrone, 3M, meow, mcat, 3-meph

Psychoactive Class

Stimulant Entactogen

Chemical Class

Cathinone (substituted)