Ketamine

K, Ket, Kitty, Special K, Cat Tranquilizer

Psychoactive Class

Chemical Class

Ketamine is a dissociative anesthetic¹ of the arylcyclohexylamine class, developed in the early 1960s by Parke-Davis Laboratories¹ as a replacement for phencyclidine (PCP). Widely employed in both human and veterinary medicine¹, it is considered the archetypal dissociative substance. Recreational use became widespread through the 1990s rave and nightclub scenes. More recently, it has attracted significant clinical interest for its ability to rapidly alleviate treatment-resistant depression¹ and suicidal ideation¹.

Dosage & Duration

Dosage

Threshold10-15 mg

Light15-30 mg

Moderate30-75 mg

Strong60-125 mg

Heavy100-250 mg

Bioavailability

45–50%

Duration

Onset10-30 minutes

Come Up5-20 minutes

Peak45-90 minutes

Offset3-6 hours

After Effects4-8 hours

Subjective Effects

Effects vary widely by individual, dose, and context.

Physical

The subjective physical effects of ketamine can be broken down into eight components all of which progressively intensify proportional to dosage.

Tactile disconnection Physical autonomy

Cognitive

In comparison to other dissociatives, the cognitive effects of ketamine are often described as particularly forceful towards introspection and with more analytical thought process when compared to that of DXM and MXE.

Consciousness disconnection Ego suppression, loss and death Time distortion Introspection Deja-Vu Personal bias suppression Conceptual thinking Direct communication with the subconscious Unity and interconnectedness

Visual

This substance does not enhance visual stimuli; instead it tends to degrade and decrease visual aptitude in a variety of ways.

Distortions

Ketamine exhibits a full array of dissociative distortions and alterations in visual perception.

Perspective distortions Environmental cubismEnvironmental orbismScenery slicing

Geometry

The visual geometry found within ketamine can be described as very brightly coloured in scheme when compared to that of MXE but not as complex or psychedelic as that of DXM. It does not extend beyond level 4 and can be comprehensively described through its variations as simplistic in complexity, algorithmic in style, synthetic in feel, unstructured in organization, dimly lit in lighting, multicoloured in scheme, glossy in shading, soft in edges, large in size, fast in speed, smooth in motion, equal in rounded and angular corners, immersive in depth and consistent in intensity.

Hallucinatory States

At high dosages, ketamine can produce a full range of high level hallucinatory states in a fashion that is less consistent and reproducible than that of many other commonly used psychedelics.

Suppressions

Visual acuity suppression

Auditory

The auditory effects of ketamine are common in their occurrence and exhibit a range of effects.

Enhancements Suppression Distortions Hallucinations

Forked from Subjective Effect Documentation

by Josie KinsMay 2013.

Reagent Testing

Loading reagent data

Expected colorimetric results are being prepared.

Pharmacology

Pharmacodynamics

Ketamine principally acts as a noncompetitive, open-channel², voltage-dependent antagonist of the NMDA receptor, an ionotropic glutamate receptor that facilitates the entry of cations into neurons. It binds to the dizocilpine (PCP) site within the ion channel pore, blocking the influx of sodium, potassium, and calcium when the channel is occupied. Ketamine is a racemic mixture of two enantiomers, esketamine (S-ketamine) and arketamine (R-ketamine), with S-ketamine displaying approximately 3- to 4-fold greater NMDA receptor affinity than R-ketamine (Ki values of 0.30 μM and 1.4 μM, respectively)². In the presence of physiological magnesium concentrations, ketamine shows a degree of NMDA receptor subunit selectivity, with its affinity for GluN2C- and GluN2D-containing receptors being less reduced by magnesium than its affinity for GluN2A- and GluN2B-containing receptors².

Ketamine is not selective for NMDA receptors, though a broad screening study found that at 10 μM, ketamine and norketamine primarily affected NMDA receptors and did not appreciably interact with muscarinic receptors, opioid receptors, sigma receptors, serotonin receptors, or monoamine transporters. Additional reported targets include the D2 dopamine receptor (partial agonist), kappa-opioid receptor (agonist), norepinephrine transporter (inhibitor), 5-HT3A receptor (potentiator), substance-P receptor (antagonist), and cholinesterase (inhibitor), though whether ketamine is a D2 receptor agonist remains controversial, with later studies reporting affinity greater than 10 μM. Acute NMDA receptor blockade results in increased glutamate release, which activates AMPA receptors and modulates downstream signaling pathways including upregulation of BDNF, activation of mTOR, and inhibition of eEF2 kinase phosphorylation, promoting rapid synaptic protein synthesis and neuroplasticity. Ketamine is classified as a psychoplastogen, meaning it can rapidly and durably promote neuroplasticity. The metabolite (2R,6R)-hydroxynorketamine has been found to indirectly activate AMPA receptors without altering NMDA receptor function and may contribute to antidepressant-relevant effects, though its necessity for ketamine's efficacy remains uncertain.

Pharmacokinetics

Ketamine is rapidly absorbed and undergoes extensive hepatic metabolism, primarily via CYP3A4 and CYP2B6, yielding norketamine through N-demethylation³. Norketamine is subsequently converted by CYP2A6 and CYP2B6 into hydroxynorketamines (HNKs) and dehydronorketamine (DHNK)². Additional metabolic pathways include hydroxylation of the cyclohexanone ring, conjugation with glucuronic acid, and dehydration of hydroxylated metabolites to form cyclohexene derivatives². Conjugated hydroxylated derivatives account for approximately 80% of urinary metabolites², followed by dehydronorketamine at about 16%. Overall, 85–95% of the administered dose is recovered in urine, primarily as metabolites, with minor elimination via bile and feces. Following intravenous administration, approximately 91% is recovered in urine and 3% in feces. Oral bioavailability is low (16–24%) due to substantial first-pass metabolism, while intramuscular bioavailability is approximately 93%. The distribution half-life is approximately 1.95 minutes, and the elimination half-life is approximately 120 minutes following intravenous administration. Clearance is high, approximately 95 L/h/70 kg.

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.

AlcoholDiphenhydramineGHB/GBLOpioidsTramadol

Caution

Use caution

These combinations are not usually physically harmful, but may produce undesirable effects, such as physical discomfort or overstimulation. Extreme use may cause physical health issues. Synergistic effects may be unpredictable. Care should be taken when choosing to use this combination.

AmphetaminesBenzodiazepinesCocaineMAOIsPregabalin

TripSit

Tolerance

Full Tolerance

Tolerance to dissociative, euphoric, hallucinogenic, and psychotomimetic effects can develop after sustained repeated use. The pace varies widely between individuals: some people report tolerance after one night of heavy use, while others need weeks of regular consumption before noticing it. High-dose nonmedical ketamine use can readily produce tolerance to its main effects.

Cross Tolerance

Dissociatives

Baseline Reset

Tolerance may decline after abstinence, but the time needed for a full reset depends on individual physiology, amount and frequency of use, and total exposure duration. Some users report needing a month or longer for tolerance to return to baseline. Dissociatives such as ketamine are also reported to produce long-lasting or permanent tolerance ('permatolerance') that builds gradually apart from ordinary tolerance, with many chronic users saying they need much higher doses to reach dissociation even after long breaks.

Harm Potential

Addiction & Dependence

Psychological

Moderate

Moderate to high abuse potential with risk of psychological dependence developing with chronic use.⁴ Compulsive redosing is commonly reported, particularly with insufflation. The short duration of effects promotes bingeing patterns.

Physical

Low

Physical dependence can develop with daily use. Withdrawal symptoms reported include anxiety, tremor, sweating, and palpitations following attempts to stop.⁴

Toxicity

Urinary System

Frequent heavy use can cause ketamine-induced cystitis, reduced bladder capacity, urge incontinence, and painful haematuria; these effects are strongly associated with chronic abuse patterns, with 20-30% of frequent users reporting bladder complaints.⁵

Hepatic

Liver toxicity has been reported with higher doses and repeated administration; in chronic high-dose users, the frequency of liver injury is approximately 10%.⁸

Renal

Chronic heavy use has been associated with kidney damage ranging from hydronephrosis to acute kidney injury; rhabdomyolysis causing kidney failure has been reported in overdose cases.⁹

Central Nervous System

Chronic heavy use is associated with cognitive deficits in memory and learning, with imaging studies showing reductions in white and grey matter and brain atrophy in frequent users;¹⁰ infrequent users do not appear to differ from controls on cognitive measures.¹¹

Antibiotic Function

Possible

Some evidence suggests ketamine may have antibiotic properties at higher doses, though how this affects normal human use is unclear.

Psychosis Risk

At anesthetic doses, 10-20% of adults experience adverse psychiatric reactions during emergence, ranging from dysphoria to hallucinations and emergence delirium.¹³ Regular use is associated with paranoia, egocentrism, and increased delusional symptoms.¹¹ Chronic heavy use may lead to persistent psychotic symptoms.

Seizure Risk

Seizures are rare but have been reported at very high or overdose-level doses. Tonic-clonic movements occur commonly at anesthetic doses but are distinct from true epileptic seizures.¹³

History & Culture

Synthesis and Medical Development

Ketamine was first synthesized in 1962 by American scientist Calvin Stevens at Parke Davis Laboratories, initially designated "CI581."¹⁴ Stevens sought a safer anesthetic to replace phencyclidine, which produced severe and prolonged hallucinogenic effects upon…

Trip Reports

Legality

International

UN Single Convention on Narcotic Drugs 1961: not listed

UN Convention on Psychotropic Substances 1971: not listed

UN Convention against Illicit Traffic 1988: not listed

By Country

United StatesPrescription onlySchedule III

21 CFR § 1308.13(c)(7)^{104105106107108109}

Ketamine, including its salts and isomers, is a federal Schedule III controlled substance under 21 CFR § 1308.13(c)(7), effective August 12, 1999. Federal law makes knowingly or intentionally possessing it without a valid prescription or other authorization unlawful, and prohibits its manufacture, distribution, or dispensing except as authorized. A Schedule III prescription drug may be dispensed only on a written or oral prescription.

By state

Across the 50 states, D.C., and the permanent territories, most jurisdictions treat ketamine consistently with federal law, though a number of states impose their own controls or classifications that diverge from the federal position.

Alaska

Prescription onlySchedule IVA

Texas

IllegalPenalty Group 1

AustriaIllegal (analog/blanket ban)Anlage II

Neue-Psychoaktive-Substanzen-Verordnung, Anlage II Z 8; Neue-Psychoaktive-Substanzen-Gesetz §§ 4–5^2021222324

Ketamine falls within the NPSV arylcyclohexylamine class. Since 1 January 2012, profit-motivated manufacture, import, export, supply, or procurement of it for psychoactive use in humans is punishable by up to two years’ imprisonment; substances without a demonstrated lawful purpose may be confiscated. Licensed medicinal ketamine is also classified as NR under the Rezeptpflichtverordnung, requiring a prescription and prohibiting repeat dispensing.

BrazilPrescription onlyLista B1

RDC nº 676/2022 (atualização do Anexo I da Portaria SVS/MS nº 344/1998)^27282930

Ketamine is listed as a psychotropic substance in Lista B1 and is subject to a Notificação de Receita “B”, rather than the two-copy special-control prescription used for Lista C1. Effective 2 May 2022, medicines containing ketamine must bear the statement “USO RESTRITO A ESTABELECIMENTOS DE SAÚDE” (“use restricted to health establishments”).

CanadaIllegalSchedule I

Controlled Drugs and Substances Act^31323334

Ketamine has been expressly listed in Schedule I, item 14(1), of the Controlled Drugs and Substances Act since 31 August 2005. Unauthorized possession, trafficking or sale, import or export, and production are prohibited; authorized medical, scientific, and industrial activities remain permitted under the applicable regulatory framework. Ketamine is named as a phencyclidine analogue in the Schedule I entry.

CroatiaRestrictedList 2

Popis droga, psihotropnih tvari i biljaka iz kojih se može dobiti droga te tvari koje se mogu uporabiti za izradu droga³⁷

Possession and distribution regulated under national drug legislation.

DenmarkRestrictedListe B

Bekendtgørelse om euforiserende stoffer³⁹⁴⁰

Illegal except for scientific and medicinal uses as of February 8, 2008.

GermanyIllegal (analog/blanket ban)Arylcyclohexylamines

Neue-psychoaktive-Stoffe-Gesetz (NpSG)^{48495051525354}

Ketamine has been captured since 3 July 2021 by item 6 of the NpSG annex, the group of arylcyclohexylamine derivatives. For ketamine that is not an Arzneimittel, the NpSG prohibits trade, placing on the market, manufacture, import, export, acquisition, possession, and administering; trade, placing on the market, and specified manufacture or import are punishable by up to three years’ imprisonment or a fine. The NpSG does not apply to medicines, and ketamine-containing medicines remain prescription-only under AMVV Annex 1, requiring a medical, dental, or veterinary prescription for dispensing.

IndiaUnscheduledCitation needed

Ketamine does not appear in the Narcotic Drugs and Psychotropic Substances Act, 1985, and is reportedly available over the counter in many pharmacies.

IrelandPrescription onlySchedule 3

Misuse of Drugs Regulations 2017 (S.I. No. 173/2017)⁶²

Ketamine is a Schedule 3 controlled drug under the Misuse of Drugs Regulations 2017. The schedule also controls its stereoisomers, salts, and preparations containing it, subject to the regulation’s stated exceptions.

JapanIllegalNarcotic

Narcotics and Psychotropics Control Act and Cabinet Order designating narcotics⁶⁴⁶⁵

Classified as a narcotic under the Narcotic and Psychotropic Drugs Control Act (麻薬及び向精神薬取締法).

MalaysiaIllegalCitation needed

Controlled under Section 39b of the Dangerous Drugs Act. Possession and sale are illegal.

NetherlandsUnscheduled (medication)Citation needed

Treated as a medication rather than a controlled substance. Not listed in List 1 or 2 of the Opium Act. Sales require appropriate pharmaceutical licensing.

NorwayPrescription onlyNarkotikalisten

Forskrift om narkotika (narkotikaforskriften)^777879808182

Ketamine has been listed by name as a narcotic in Norway’s Narkotikalisten since 1 January 2026; the current list identifies it as 2-(2-klorfenyl)-2-(metylamino)sykloheksan-1-on (CAS 6740-88-1). Ketamine and esketamine preparations remain in prescription group A. Possession or use without lawful access is prohibited; manufacture requires express authorization, import and export require a certificate, and trade, supply, and dispatch are limited to medical or scientific use.

PolandPrescription onlyGroup II-P

Regulation of the Minister of Health on the list of psychotropic substances, narcotic drugs and new psychoactive substances⁸⁴

Illegal to possess, manufacture, and sell except for authorized medical purposes.

SingaporeRestrictedClass A

Misuse of Drugs Act 1973⁸⁶⁸⁷⁸⁸

Class A controlled drug. Traffickers face 5-20 years imprisonment and 5-15 strokes of the cane. Possession of more than 113g is deemed trafficking.

South AfricaPrescription onlySchedule 5

Medicines and Related Substances Act 101 of 1965, Consolidated Schedules⁹³

Ketamine is a Schedule 5 substance under South Africa’s medicines scheduling framework. The current consolidated schedule is published by the national medicines regulator under the Medicines and Related Substances Act.

SpainPrescription onlyLista IV

Orden SAS/2712/2010⁹⁷

Classified as a Schedule IV substance under Spanish drug control legislation.

SwitzerlandRestrictedVerzeichnis B

Betäubungsmittelverzeichnisverordnung⁹⁹

Specifically named under Verzeichnis B. Possession or handling without a license is illegal. Medicinal use is permitted.

TurkeyGreen prescription onlyCitation needed

Available only with a 'green prescription' designation. Illegal when sold or possessed without a prescription.

AustraliaRestrictedSchedule 8

Therapeutic Goods (Poisons Standard—February 2026) Instrument 2026¹⁹

Possession, manufacture, or supply without authority is illegal. Classified as a controlled drug requiring strict regulation.

BelgiumPrescription onlyPrescription

Royal Decree of 6 September 2017 regulating narcotic and psychotropic substances²⁵²⁶

Legal for medical and veterinary use. Possession without prescription can result in arrest.

CambodiaControlledCitation needed

Not legal to possess without a prescription. Some pharmacies may sell ketamine, though most consider it forbidden.

ChinaRestricted第一类

国家药监局、公安部、国家卫生健康委关于发布药用类麻醉药品和精神药品目录的公告（2025年第55号）³⁵³⁶

Ketamine is listed as a Category I psychotropic drug in China’s 2025 medicinal psychotropic-drug directory, effective upon its publication on 28 July 2025. The Regulations on the Administration of Narcotic Drugs and Psychotropic Drugs prohibit retail sale of Category I psychotropic drugs and subject their research, production, distribution, use, storage, and transport to specialized statutory controls.

Czech RepublicPrescription onlyPříloha 7

Nařízení vlády č. 463/2013 Sb.³⁸

Available exclusively with a prescription under Nařízení vlády č. 463/2013 Sb. Sales and distribution controlled under the Medicines Act.

FrancePrescription onlyAnnexe IV

Arrêté du 22 février 1990 fixant la liste des substances classées comme stupéfiants^{41424344454647}

Ketamine, its salts, stereoisomers, and preparations are classified as narcotics in Annexe IV. The injectable-preparation exemption ended on 24 April 2017, and stereoisomers were expressly added in May 2017. Unless expressly authorized, narcotic production, manufacture, transport, import, export, possession, supply, acquisition, and use are prohibited; ketamine medicines are subject to narcotic-drug controls and may be prescribed or dispensed only as pharmaceutical specialties or preparations.

Hong KongIllegalPart I

Dangerous Drugs Ordinance (Cap. 134)^5556575859

Ketamine (氯胺酮) is listed as a dangerous drug in Part I of the First Schedule to the Dangerous Drugs Ordinance. Listed since 15 December 2000, its unauthorized possession, manufacture, supply, import and export are subject to the Ordinance’s dangerous-drug controls.

IndonesiaRestrictedObat-Obat Tertentu

Peraturan Badan Pengawas Obat dan Makanan Nomor 12 Tahun 2025 tentang Obat-Obat Tertentu yang Sering Disalahgunakan⁶⁰⁶¹

Ketamine is an Obat-Obat Tertentu yang Sering Disalahgunakan (OOT), a category expressly separate from narcotics and psychotropics. Since 2 May 2025, it may be distributed and handed over only for health services and/or scientific development. Supply to the public must occur through pharmaceutical-service facilities or other authorized facilities, and breaches by regulated facilities carry administrative sanctions.

ItalyIllegalTabella I

Ministerial Decree of 21 February 2001⁶³

In Italy, it is included in Tabella I of the drug and psychotropic substance schedules. Possession, purchase, and sale are illegal.

LuxembourgIllegalSubstances toxiques

Règlement grand-ducal modifié du 4 mars 1974 concernant certaines substances toxiques, modifié le 13 décembre 1985^66676869

Ketamine has been listed as a toxic substance in Luxembourg since 13 December 1985, when it was added to the annex to the Grand-Ducal Regulation of 4 March 1974. Under the amended Law of 19 February 1973, illicit personal acquisition, possession, transport and use of listed toxic substances are offences, while illicit production, importation, sale and circulation are criminal offences.

MexicoPrescription onlyGrupo III

Ley General de Salud, artículos 245 y 251^70717273

Ketamine is expressly listed in Grupo III of Article 245 of the Ley General de Salud; the 7 January 2014 reform included it and the current consolidated text retains it after the 15 January 2026 reform. Article 251 permits sale or supply to the public only on a physician’s prescription bearing the prescriber’s professional-registration number; it may be filled once and the dispensing pharmacy must retain it. The Reglamento de Insumos para la Salud further limits handling of psychotropics, including possession, use, manufacture, trade, import, and export, to medical or scientific purposes with prior Health Ministry authorization.

New ZealandIllegalClass C

Misuse of Drugs Act 1975⁷⁴⁷⁵⁷⁶

Ketamine is a Class C controlled drug listed in Schedule 3, Part 4 of the Misuse of Drugs Act 1975. Unauthorised import, export, production, sale, supply, possession, and use are offences, subject to the Act’s licences, exemptions, and regulations. The classification has applied since 1 December 2010.

PhilippinesPrescription onlyDangerous drug

Dangerous Drugs Board Regulation No. 3, s. 2005⁸³

Ketamine and preparations containing it are classified as dangerous drugs in the Philippines. A preparation prescribed by a licensed practitioner is excepted subject to the regulation’s vial, dosage, and duration limits.

PortugalNot scheduledNot listed

Decree-Law No. 15/93 of 22 January⁸⁵

Ketamine is not included in the controlled-substance tables annexed to Decree-Law No. 15/93. That decree applies its drug-control regime to the plants, substances, and preparations listed in its annexed tables.

SlovakiaPrescription onlyII. SKUPINA

Act No. 139/1998 Z. z. on narcotic drugs, psychotropic substances and preparations (current consolidated text effective 1 January 2026)^89909192

Ketamine has been listed as a Group II narcotic drug since 1 January 2010 and remains so in the current consolidated Act No. 139/1998 Z. z. Medicines containing a Group II narcotic require a special prescription form. Manufacture, import, export, distribution, dispensing, research, and other handling require statutory authorization for health or veterinary purposes; unauthorized possession, production, and trade are criminal offences.

South KoreaRestrictedAnnex 4

Enforcement Decree of the Narcotics Control Act⁹⁴⁹⁵⁹⁶

Ketamine is listed in Annex 4 as a psychotropic drug under Article 2(3)(b) of South Korea’s Narcotics Control Act framework. Persons who are not authorized narcotics handlers may not possess, use, import, export, manufacture, sell, provide, or otherwise handle it except in the Act’s specified circumstances, including lawful medical supply.

SwedenPrescription onlyFörteckning IV

LVFS 2011:10⁹⁸

Scheduled as of July 1, 2005 following increased reports of recreational misuse.

TaiwanRestrictedSchedule III

Controlled Drugs Act¹⁰⁰¹⁰¹

Controlled under national narcotics legislation with restrictions on possession and distribution.

United KingdomPrescription onlyClass B

Misuse of Drugs Act 1971 (Ketamine etc.) (Amendment) Order 2014¹⁰²¹⁰³

Reclassified as a Class B drug under the Misuse of Drugs Act 1971 on June 10, 2014.¹⁰³ Previously classified as Class C from January 1, 2006. Prior to 2006, possession was legal though sales required licensing.

References

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Citations

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Ketamine

K, Ket, Kitty, Special K, Cat Tranquilizer

Psychoactive Class

Dissociative Hallucinogen

Chemical Class

Arylcyclohexylamine

Dosage & Duration

Dosage

Threshold10-15 mg

Light15-30 mg

Moderate30-75 mg

Strong60-125 mg

Heavy100-250 mg

Bioavailability

45–50%

Duration

Onset10-30 minutes

Come Up5-20 minutes

Peak45-90 minutes

Offset3-6 hours

After Effects4-8 hours

Subjective Effects

Effects vary widely by individual, dose, and context.

Physical

The subjective physical effects of ketamine can be broken down into eight components all of which progressively intensify proportional to dosage.

Tactile disconnection Physical autonomy

Cognitive

Visual

This substance does not enhance visual stimuli; instead it tends to degrade and decrease visual aptitude in a variety of ways.

Distortions

Ketamine exhibits a full array of dissociative distortions and alterations in visual perception.

Perspective distortions Environmental cubismEnvironmental orbismScenery slicing

Geometry

Hallucinatory States

At high dosages, ketamine can produce a full range of high level hallucinatory states in a fashion that is less consistent and reproducible than that of many other commonly used psychedelics.

Suppressions

Visual acuity suppression

Auditory

The auditory effects of ketamine are common in their occurrence and exhibit a range of effects.

Enhancements Suppression Distortions Hallucinations

Forked from Subjective Effect Documentation

by Josie KinsMay 2013.

Reagent Testing

Loading reagent data

Expected colorimetric results are being prepared.

Pharmacology

Pharmacodynamics

Pharmacokinetics

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.

AlcoholDiphenhydramineGHB/GBLOpioidsTramadol

Caution

Use caution

AmphetaminesBenzodiazepinesCocaineMAOIsPregabalin

TripSit

Tolerance

Full Tolerance

Cross Tolerance

Dissociatives

Baseline Reset

Harm Potential

Addiction & Dependence

Psychological

Moderate

Physical

Low

Physical dependence can develop with daily use. Withdrawal symptoms reported include anxiety, tremor, sweating, and palpitations following attempts to stop.⁴

Toxicity

Urinary System

Hepatic

Liver toxicity has been reported with higher doses and repeated administration; in chronic high-dose users, the frequency of liver injury is approximately 10%.⁸

Renal

Chronic heavy use has been associated with kidney damage ranging from hydronephrosis to acute kidney injury; rhabdomyolysis causing kidney failure has been reported in overdose cases.⁹

Central Nervous System

Antibiotic Function

Possible

Some evidence suggests ketamine may have antibiotic properties at higher doses, though how this affects normal human use is unclear.

Psychosis Risk

Seizure Risk

Seizures are rare but have been reported at very high or overdose-level doses. Tonic-clonic movements occur commonly at anesthetic doses but are distinct from true epileptic seizures.¹³

History & Culture

Synthesis and Medical Development

Trip Reports

Legality

International

UN Single Convention on Narcotic Drugs 1961: not listed

UN Convention on Psychotropic Substances 1971: not listed

UN Convention against Illicit Traffic 1988: not listed

By Country

United StatesPrescription onlySchedule III

21 CFR § 1308.13(c)(7)^{104105106107108109}

By state

Alaska

Prescription onlySchedule IVA

Texas

IllegalPenalty Group 1

AustriaIllegal (analog/blanket ban)Anlage II

Neue-Psychoaktive-Substanzen-Verordnung, Anlage II Z 8; Neue-Psychoaktive-Substanzen-Gesetz §§ 4–5^2021222324

BrazilPrescription onlyLista B1

RDC nº 676/2022 (atualização do Anexo I da Portaria SVS/MS nº 344/1998)^27282930

CanadaIllegalSchedule I

Controlled Drugs and Substances Act^31323334

CroatiaRestrictedList 2

Popis droga, psihotropnih tvari i biljaka iz kojih se može dobiti droga te tvari koje se mogu uporabiti za izradu droga³⁷

Possession and distribution regulated under national drug legislation.

DenmarkRestrictedListe B

Bekendtgørelse om euforiserende stoffer³⁹⁴⁰

Illegal except for scientific and medicinal uses as of February 8, 2008.

GermanyIllegal (analog/blanket ban)Arylcyclohexylamines

Neue-psychoaktive-Stoffe-Gesetz (NpSG)^{48495051525354}

IndiaUnscheduledCitation needed

Ketamine does not appear in the Narcotic Drugs and Psychotropic Substances Act, 1985, and is reportedly available over the counter in many pharmacies.

IrelandPrescription onlySchedule 3

Misuse of Drugs Regulations 2017 (S.I. No. 173/2017)⁶²

JapanIllegalNarcotic

Narcotics and Psychotropics Control Act and Cabinet Order designating narcotics⁶⁴⁶⁵

Classified as a narcotic under the Narcotic and Psychotropic Drugs Control Act (麻薬及び向精神薬取締法).

MalaysiaIllegalCitation needed

Controlled under Section 39b of the Dangerous Drugs Act. Possession and sale are illegal.

NetherlandsUnscheduled (medication)Citation needed

Treated as a medication rather than a controlled substance. Not listed in List 1 or 2 of the Opium Act. Sales require appropriate pharmaceutical licensing.

NorwayPrescription onlyNarkotikalisten

Forskrift om narkotika (narkotikaforskriften)^777879808182

PolandPrescription onlyGroup II-P

Regulation of the Minister of Health on the list of psychotropic substances, narcotic drugs and new psychoactive substances⁸⁴

Illegal to possess, manufacture, and sell except for authorized medical purposes.

SingaporeRestrictedClass A

Misuse of Drugs Act 1973⁸⁶⁸⁷⁸⁸

Class A controlled drug. Traffickers face 5-20 years imprisonment and 5-15 strokes of the cane. Possession of more than 113g is deemed trafficking.

South AfricaPrescription onlySchedule 5

Medicines and Related Substances Act 101 of 1965, Consolidated Schedules⁹³

SpainPrescription onlyLista IV

Orden SAS/2712/2010⁹⁷

Classified as a Schedule IV substance under Spanish drug control legislation.

SwitzerlandRestrictedVerzeichnis B

Betäubungsmittelverzeichnisverordnung⁹⁹

Specifically named under Verzeichnis B. Possession or handling without a license is illegal. Medicinal use is permitted.

TurkeyGreen prescription onlyCitation needed

Available only with a 'green prescription' designation. Illegal when sold or possessed without a prescription.

AustraliaRestrictedSchedule 8

Therapeutic Goods (Poisons Standard—February 2026) Instrument 2026¹⁹

Possession, manufacture, or supply without authority is illegal. Classified as a controlled drug requiring strict regulation.

BelgiumPrescription onlyPrescription

Royal Decree of 6 September 2017 regulating narcotic and psychotropic substances²⁵²⁶

Legal for medical and veterinary use. Possession without prescription can result in arrest.

CambodiaControlledCitation needed

Not legal to possess without a prescription. Some pharmacies may sell ketamine, though most consider it forbidden.

ChinaRestricted第一类

国家药监局、公安部、国家卫生健康委关于发布药用类麻醉药品和精神药品目录的公告（2025年第55号）³⁵³⁶

Czech RepublicPrescription onlyPříloha 7

Nařízení vlády č. 463/2013 Sb.³⁸

Available exclusively with a prescription under Nařízení vlády č. 463/2013 Sb. Sales and distribution controlled under the Medicines Act.

FrancePrescription onlyAnnexe IV

Arrêté du 22 février 1990 fixant la liste des substances classées comme stupéfiants^{41424344454647}

Hong KongIllegalPart I

Dangerous Drugs Ordinance (Cap. 134)^5556575859

IndonesiaRestrictedObat-Obat Tertentu

Peraturan Badan Pengawas Obat dan Makanan Nomor 12 Tahun 2025 tentang Obat-Obat Tertentu yang Sering Disalahgunakan⁶⁰⁶¹

ItalyIllegalTabella I

Ministerial Decree of 21 February 2001⁶³

In Italy, it is included in Tabella I of the drug and psychotropic substance schedules. Possession, purchase, and sale are illegal.

LuxembourgIllegalSubstances toxiques

Règlement grand-ducal modifié du 4 mars 1974 concernant certaines substances toxiques, modifié le 13 décembre 1985^66676869

MexicoPrescription onlyGrupo III

Ley General de Salud, artículos 245 y 251^70717273

New ZealandIllegalClass C

Misuse of Drugs Act 1975⁷⁴⁷⁵⁷⁶

PhilippinesPrescription onlyDangerous drug

Dangerous Drugs Board Regulation No. 3, s. 2005⁸³

PortugalNot scheduledNot listed

Decree-Law No. 15/93 of 22 January⁸⁵

SlovakiaPrescription onlyII. SKUPINA

Act No. 139/1998 Z. z. on narcotic drugs, psychotropic substances and preparations (current consolidated text effective 1 January 2026)^89909192

South KoreaRestrictedAnnex 4

Enforcement Decree of the Narcotics Control Act⁹⁴⁹⁵⁹⁶

SwedenPrescription onlyFörteckning IV

LVFS 2011:10⁹⁸

Scheduled as of July 1, 2005 following increased reports of recreational misuse.

TaiwanRestrictedSchedule III

Controlled Drugs Act¹⁰⁰¹⁰¹

Controlled under national narcotics legislation with restrictions on possession and distribution.

United KingdomPrescription onlyClass B

Misuse of Drugs Act 1971 (Ketamine etc.) (Amendment) Order 2014¹⁰²¹⁰³

References

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Ketamine

Contents

Dosage & Duration

Dosage

Duration

Subjective Effects

Physical

Cognitive

Visual

Distortions

Geometry

Hallucinatory States

Suppressions

Auditory

Reagent Testing

Pharmacology

Pharmacodynamics

Pharmacokinetics

Interactions

Dangerous

Caution

Tolerance

Harm Potential

Addiction & Dependence

Psychological

Physical

Toxicity

Psychosis Risk

Seizure Risk

History & Culture

Synthesis and Medical Development

Trip Reports

Legality

International

By Country

References

Source Pages

Citations

Further Reading

Suggest an edit

Ketamine

Contents

Dosage & Duration

Dosage

Duration

Subjective Effects

Physical

Cognitive

Visual

Distortions

Geometry

Hallucinatory States

Suppressions

Auditory

Reagent Testing

Pharmacology

Pharmacodynamics

Pharmacokinetics

Interactions

Dangerous

Caution

Tolerance

Harm Potential

Addiction & Dependence

Psychological

Physical

Toxicity

Psychosis Risk

Seizure Risk

History & Culture

Synthesis and Medical Development

Trip Reports

Trip Reports

Legality

International

By Country

References

Source Pages

Citations

Further Reading