Methoxetamine
2-(ethylamino)-2-(3-methoxyphenyl)cyclohexan-1-one
Overview
Methoxetamine belongs to Dissociatives / Arylcyclohexylamines.
Effects
- Dissociation with depersonalisation and derealisation, dreamlike and anaesthetic states, and a euphoria and mental space often described as clearer or more stimulating than ketamine's.
- Sensory and motor changes: numbness, visual and tactile disconnection, and at higher doses the immersive 'hole'. Ataxia, slurred speech and nystagmus.
- Sympathetic stimulation (raised heart rate and blood pressure). After-effects can include lingering confusion, dissociation and low mood, and, after a cerebellar reaction, days of unsteadiness.
Dosing & duration
Insufflated, oral, sublingual or rectal. Values below are approximate ORAL figures. MXE is potent and much longer-acting than ketamine.. MXE is potent and long-acting (4–6 h oral) with a slow onset, and its steep dose–response makes overshooting easy: start very low, use an accurate milligram scale, and wait well beyond the expected onset before considering a redose (delayed onset is a common cause of overdose). Insufflated doses are a little lower and faster. Avoid combining with other depressants or stimulants, and never dose in an unsafe setting: heavy dissociation removes coordination and awareness.
Dose ranges
5 mg
10–25 mg
25–45 mg
45–70 mg
70 mg +
Duration
15–30 min (oral), 5–20 min insufflated
4–6 h (oral)
6–48 h
Chemical & Physical Properties
| Formula | C15H21NO2 |
| Molar mass | 247.33 g/mol |
| State | Solid (usually the hydrochloride salt, crystalline) |
| Melting point | Not reported |
| Boiling point | Not reported |
| Density | Not reported |
| Vapor pressure | Not reported |
| pKa | Not reported |
| LogP | 2.3 (predicted, XLogP3) |
| Solubility | Not reported |
| Refractive index | Not reported |
Identifiers & Synonyms
| CAS | Not reported |
| CAS (enantiomer) | |
| PubChem CID | 52911279 |
| InChIKey | LPKTWLVEGBNOOX-UHFFFAOYSA-N |
| InChI | InChI=1S/C15H21NO2/c1-3-16-15(10-5-4-9-14(15)17)12-7-6-8-13(11-12)18-2/h6-8,11,16H,3-5,9-10H2,1-2H3 |
| SMILES | CCNC1(CCCCC1=O)C2=CC(=CC=C2)OC |
Synonyms
- MXE
- Mexxy
- 3-MeO-2-Oxo-PCE
Pharmacodynamics & Biochemistry
Methoxetamine (MXE, 'Mexxy') is a dissociative anaesthetic of the arylcyclohexylamine class: a designer analogue of ketamine carrying an N-ethyl group (instead of N-methyl), a 3-methoxy ring substituent and a cyclohexanone core. Like ketamine and PCP it is a non-competitive NMDA-receptor antagonist, binding the PCP/MK-801 channel site to block glutamatergic transmission. Roth et al. (2013) measured a Ki of 337 ± 76 nM at the NMDA PCP site, comparable to ketamine. This blockade produces the characteristic dose-dependent dissociation, analgesia, anaesthesia and, at high doses, the immersive 'hole' state. Unlike ketamine, MXE was designed to add serotonergic activity: in the same study it showed submicromolar affinity for the serotonin transporter (SERT) while being essentially inactive at the dopamine and noradrenaline transporters (Ki > 10 µM). That serotonergic component, together with a longer duration and greater potency than ketamine, gives MXE a somewhat different, often more stimulating and euphoric character. It is used as the racemate.
Biological targets
- NMDA
- SERT
Binding & functional measurements
| Target | Measurement | Species |
|---|---|---|
| NMDA receptor | Ki 259 nM | Rat |
| Serotonin transporter | Ki 481 nM | Human |
Pharmacokinetics
| Bioavailability | Not reported |
| Tmax | Not reported |
| Half-life | ≈3–6 h (long relative to ketamine) |
| Vd | Not reported |
| Protein binding | Not reported |
| Metabolism | Hepatic: O-demethylation (to O-desmethyl-methoxetamine/normethoxetamine) and N-deethylation, plus hydroxylation (CYP-mediated) |
| Excretion | Renal |
Toxicology & Safety
Not reported
Methoxetamine is considerably more potent and much longer-acting than ketamine, and it was aggressively, and falsely, marketed as a 'bladder-safe' ketamine substitute. Its long duration and steep dose–response make overshooting easy: a few extra milligrams can push a user into heavy dissociation, the immersive 'M-hole', catatonia, vomiting with aspiration risk, and dangerous loss of coordination and awareness. MXE causes more cardiovascular stimulation than ketamine (tachycardia and hypertension are common) and has produced a distinctive acute cerebellar toxicity, ataxia, slurred speech, nystagmus and unsteady gait, that can last for days. The 'bladder-sparing' claim was not borne out: animal studies show ketamine-like bladder inflammation and fibrosis, so urinary-tract damage from regular use should be expected. It is strongly dissociative and disinhibiting, so injuries and dangerous behaviour occur. The delayed onset tempts compulsive redosing, a common cause of accidental overdose, and combining it with other depressants (alcohol, benzodiazepines, opioids, GHB) or stimulants sharply raises the risk. Deaths and hospitalisations have occurred, usually with high doses or drug combinations.[3][4]
Legal Status
US: Schedule I. UK: Class B. DE: BtMG Anlage I
Interactions & Contraindications
Drug interactions
Contraindications
No interactions or contraindications listed.
Usage & Context
- A recreational dissociative and one of the first 'research chemical' ketamine substitutes to be widely sold online (around 2010–2012), taken for dissociation, euphoria, anaesthesia and out-of-body / 'hole' experiences: insufflated, swallowed, or used sublingually or rectally.
- Marketed as a legal, supposedly 'bladder-safe' alternative to ketamine. Its rapid spread and associated harms made it an early test case for emergency drug legislation: the first substance placed under a UK Temporary Class Drug Order (2012).
- No accepted medical use. Now controlled in most jurisdictions.
Sources & Evidence
- PubChem: Methoxetamine (CID 52911279) — identifiers & computed properties
- Roth BL, Gibbons S, Arunotayanun W, et al. (2013). The ketamine analogue methoxetamine and 3- and 4-methoxy analogues of phencyclidine are high affinity and selective ligands for the glutamate NMDA receptor. PLoS One 8:e59334.
PMID 23527166 · doi:10.1371/journal.pone.0059334
- Wikipedia: Methoxetamine — pharmacology (NMDA antagonist, SERT activity), harms (cerebellar/urinary toxicity) & legal status CC BY-SA 4.0
- PsychonautWiki: Methoxetamine — dosage, duration & subjective effects CC BY-SA 4.0
- DEA Diversion Control Division: Controlled Substance Schedules — methoxetamine is Schedule I (final rule 2022)
- GOV.UK: Controlled drugs list — methoxetamine is Class B (Misuse of Drugs Act 1971) OGL v3.0
- Anlage I BtMG — Betäubungsmittelgesetz (Gesetze im Internet): Methoxetamin (MXE), nicht verkehrsfähig