Ketamine Stats & Data
CNC1(CCCCC1=O)c1ccccc1ClYQEZLKZALYSWHR-UHFFFAOYSA-NPharmacology
DrugBankDescription
Ketamine is an NMDA receptor antagonist with a potent anesthetic effect. It was developed in 1963 as a replacement for phencyclidine (PCP) by Calvin Stevens at Parke Davis Laboratories. It started being used for veterinary purposes in Belgium and in 1964 was proven that compared to PCP, it produced minor hallucinogenic effects and shorter psychotomimetic effects. It was FDA approved in 1970, and from there, it has been used as an anesthetic for children or patients undergoing minor surgeries but mainly for veterinary purposes.
Mechanism of Action
Ketamine interacts with N-methyl-D-aspartate (NMDA) receptors, opioid receptors, monoaminergic receptors, muscarinic receptors and voltage sensitive Ca ion channels. Unlike other general anaesthetic agents, ketamine does not interact with GABA receptors.
Pharmacodynamics
Ketamine is a rapid-acting general anesthetic producing an anesthetic state characterized by profound analgesia, normal pharyngeal-laryngeal reflexes, normal or slightly enhanced skeletal muscle tone, cardiovascular and respiratory stimulation, and occasionally a transient and minimal respiratory depression. The anesthetic state produced by Ketamine has been termed as "dissociative anesthesia" in that it appears to selectively interrupt association pathways of the brain before producing somesthetic sensory blockade. It may selectively depress the thalamoneocortical system before significantly obtunding the more ancient cerebral centers and pathways (reticular-activating and limbic systems). Ketamine enhances descending inhibiting serotoninergic pathways and can exert antidepressive effects. These effects are seen in concentrations ten times lower than the needed concentration for anesthetic proposes. The effect of ketamine can be described as analgesic by the prevention of central sensitization in dorsal horn neurons as well as by the inhibition on the synthesis of nitric oxide. Ketamine can present cardiovascular changes and bronchodilatation.
Metabolism
Ketamine presents a mainly hepatic metabolism and its major metabolite is norketamine. The biotransformation of ketamine corresponds to N-dealkylation, hydroxylation of the cyclohexone ring, conjugation to glucuronic acid and dehydration of the hydroxylated metabolites for the formation of cyclohexene derivatives.
Absorption
Ketamine absorption is very rapid and the bioavailability is around 93%. After the first pass metabolism, only 17% of the administered dose is absorbed. It distributes very rapidly and presents a distribution half-life of 1.95 min. The Cmax levels at peak reach 0.75 mcg/ml in plasma and 0.2 mcg/ml in cerebrospinal fluid.
Toxicity
Preclinical studies related to the blocking of NMDA receptors have shown an increase in apoptosis in the developing brain which results in cognitive deficits when used for longer than 3 hours. Toxicity studies regarding carcinogenesis have not been performed. Regarding mutagenesis and fertility, ketamine showed to be clastogenic and to not have effects on fertility.
Indication
Ketamine is indicated as an anesthetic agent for recommended diagnostic and surgical procedures. If skeletal muscle relaxation is needed, it should be combined with a muscle relaxant. If the surgical procedure involves visceral pain, it should be supplemented with an agent that obtunds visceral pain. Ketamine can be used for induction of anesthesia prior other general anesthetic agents and as a supplement of low potency agents. Reports have indicated a potential use of ketamine as a therapeutic tool for the management of depression when administered in lower doses. These reports have increased the interest for ketamine in this area and several clinical trials are launched for this indication.
Half-life
The reported half-life in preclinical studies for ketamine is 186 min.
Protein Binding
The plasma protein binding of ketamine accounts for 53.5% of the administered dose.
Elimination
Pharmacokinetic studies have resulted in the recovery of 85-95% of the administered dose in urine mainly in the form of metabolites. Some other routes of elimination of ketamine are bile and feces. When administered intravenously the resultant recovery is distributed by 91% of the administered dose in urine and 3% in feces.
Volume of Distribution
The apparent volume of distribution of the central compartment and at steady-state are 371.3 ml/kg and 4060.3 ml/kg, respectively.
Clearance
The clearance rate of ketamine is high and of around 95 L/h/70kg.
Metabolites
Receptor Profile
Receptor Actions
Receptor Binding
History & Culture
Ketamine was first synthesized in 1962 by American scientist Calvin Stevens at Parke Davis Laboratories, initially designated "CI581." Stevens sought a safer anesthetic to replace phencyclidine, which produced severe and prolonged hallucinogenic effects upon recovery from anesthesia. By 1965, ketamine had demonstrated clinical utility as an anesthetic, and researcher Edward Domino coined the term "dissociative anesthetic" to describe its unique pharmacological profile. The United States Food and Drug Administration approved ketamine for human use in 1970. Ketamine's favorable safety margin proved particularly valuable in combat medicine. Its minimal respiratory depression compared to other available anesthetics, combined with its sympathomimetic properties, led to its extensive deployment as a field anesthetic during the Vietnam War. The substance remains on the World Health Organization's Essential Drugs List as one of the minimum medical requirements for a basic healthcare system.
Recreational use of ketamine was first documented among medicinal chemists in the United States as early as 1965, spreading more widely by 1967. During the 1970s, patients recovering from ketamine anesthesia began reporting unwanted visions, drawing broader attention to the substance's psychoactive properties beyond clinical settings. In 1978, neuroscientist John Lilly published "The Scientist," an autobiographical account describing his extensive personal explorations with ketamine that helped popularize awareness of its dissociative effects among countercultural audiences. Recreational use expanded through the 1980s, and by the early 1990s ketamine had become more widespread in Europe, where it gained notoriety as an adulterant in MDMA tablets and became closely associated with the nightclub and rave scenes. By 1995, the United States Drug Enforcement Administration had placed ketamine on its emerging drugs list due to its growing presence in electronic music culture.
Ketamine has accumulated numerous street names reflecting its diverse cultural contexts, including "Special K," "K," "Kit Kat," "kitty," "cat tranquilizer" (referencing its veterinary applications), "Cat Valium," and "Jet." The term "K-hole" describes a profound dissociative state involving visual and auditory hallucinations achieved at high doses, which has become a significant concept within psychedelic culture. Several prominent figures documented their entheogenic experiences with ketamine extensively, including John Lilly, Marcia Moore, and D.M. Turner. Turner's death by drowning during unsupervised ketamine use became a cautionary example of the serious physical risks posed by the drug's dissociative and anesthetic properties. More recently, actor Matthew Perry's death in October 2023, attributed primarily to the acute effects of ketamine, brought renewed public attention to the substance's dangers. Statistical data revealed more than 90 ketamine-related deaths in England and Wales between 2005 and 2013.
The identification of ketamine's rapid antidepressant effects in 2000 represented a major breakthrough in psychiatric treatment. Research demonstrated that sub-anesthetic doses could produce immediate or near-immediate relief of depressive and suicidal symptoms, with therapeutic effects persisting up to three days following a single administration. This discovery has been characterized as the single most important advance in depression treatment in more than fifty years. The finding fundamentally shifted the direction of antidepressant research and development, generating widespread interest in NMDA receptor antagonists as a novel class of rapidly-acting treatments for mood disorders.
Subjective Effect Notes
physical: The subjective physical effects of ketamine can be broken down into eight components all of which progressively intensify proportional to dosage.
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.
Effect Profile
Curated + 920 ReportsStrong dissociative depth with moderate insight and motor impairment, low mania
User Experiences
Duration Timeline
BluelightEmpirical Duration
Erowid ReportsCommunity Effects
TripSitTolerance & Pharmacokinetics
drugs.wikiTolerance Decay
Cross-Tolerances
Demographics
Gender Distribution
Age Distribution
Reports Over Time
Effect Analysis
Erowid + BluelightEffects aggregated from 762 experience reports (712 Erowid + 208 Bluelight)
Effect Sentiment Distribution
Confidence Distribution
Positive Effects 54
Adverse Effects 57
Dose-Response Correlation
How effect frequency changes across dose levels
Insufflated
View data table
| Effect | Common (n=29) | Strong (n=27) | Heavy (n=67) |
|---|---|---|---|
| Visual Distortions | 79.3% | 66.7% | 58.2% |
| Dissociation | 62.1% | 51.9% | 71.6% |
| Focus Enhancement | 58.6% | 25.9% | 29.9% |
| Anxiety | 51.7% | 55.6% | 56.7% |
| Music Enhancement | 55.2% | 44.4% | 50.7% |
| Closed-Eye Visuals | 48.3% | 25.9% | 20.9% |
| Color Enhancement | 48.3% | 40.7% | 34.3% |
| Confusion | 48.3% | 14.8% | 37.3% |
| Euphoria | 34.5% | 33.3% | 46.3% |
| Empathy | 31.0% | 44.4% | 38.8% |
| Auditory Effects | 41.4% | 22.2% | 26.9% |
| Nausea | 37.9% | 22.2% | 23.9% |
| Motor Impairment | 37.9% | 7.4% | 9.0% |
| Stimulation | 27.6% | 37.0% | 26.9% |
| Tactile Enhancement | 20.7% | 22.2% | 28.4% |
Intramuscular
View data table
| Effect | Strong (n=16) | Heavy (n=26) |
|---|---|---|
| Visual Distortions | 50.0% | 73.1% |
| Dissociation | 50.0% | 57.7% |
| Anxiety | 43.8% | 57.7% |
| Color Enhancement | 56.2% | 34.6% |
| Music Enhancement | 56.2% | 50.0% |
| Euphoria | 50.0% | 30.8% |
| Empathy | 43.8% | 26.9% |
| Focus Enhancement | 31.2% | 42.3% |
| Auditory Effects | 31.2% | 38.5% |
| Confusion | 18.8% | 38.5% |
| Stimulation | 37.5% | 34.6% |
| Nausea | 37.5% | 30.8% |
| Tactile Enhancement | 25.0% | 26.9% |
| Ego Dissolution | 25.0% | 15.4% |
| Introspection | 25.0% | 19.2% |
Subjective Effect Ontology
Experience ReportsStructured effect tags extracted from 920 Erowid & Bluelight experience reports using a controlled vocabulary of 220+ canonical effects across 15 domains.
Auditory
Cognitive
Emotional
Gastrointestinal
Motor
Selfhood
Tactile
Visual
Dose–Effect Mapping
Experience ReportsHow reported effects shift across dose tiers, based on 712 experience reports.
| Effect | Common (n=29) | Strong (n=27) | Heavy (n=67) | |
|---|---|---|---|---|
| visual distortions | ↓ | |||
| dissociation | ↑ | |||
| focus enhancement | ↓ | |||
| anxiety | → | |||
| music enhancement | → | |||
| closed-eye visuals | ↓ | |||
| color enhancement | ↓ | |||
| confusion | ↓ | |||
| euphoria | ↑ | |||
| empathy | ↑ | |||
| auditory effects | ↓ | |||
| nausea | ↓ | |||
| motor impairment | ↓ | |||
| stimulation | → | |||
| tactile enhancement | ↑ | |||
| sedation | ↓ | |||
| muscle tension | — | ↓ | ||
| ego dissolution | → | |||
| introspection | → | |||
| body high | ↑ |
Showing top 20 of 31 effects
| Effect | Strong (n=16) | Heavy (n=26) | |
|---|---|---|---|
| visual distortions | ↑ | ||
| dissociation | ↑ | ||
| anxiety | ↑ | ||
| color enhancement | ↓ | ||
| music enhancement | → | ||
| euphoria | ↓ | ||
| empathy | ↓ | ||
| focus enhancement | ↑ | ||
| auditory effects | ↑ | ||
| confusion | ↑ | ||
| stimulation | → | ||
| nausea | ↓ | ||
| tactile enhancement | → | ||
| ego dissolution | ↓ | ||
| introspection | ↓ | ||
| memory suppression | ↑ | ||
| sedation | — | → | |
| hospital | ↓ | ||
| motor impairment | ↑ | ||
| jaw clenching | — | → |
Showing top 20 of 25 effects
Risk Escalation
Sentiment AnalysisAverage frequency of positive vs adverse effects across dose tiers (Insufflated)
View effect breakdown
Adverse Effects
| Effect | Common (n=29) | Strong (n=27) | Heavy (n=67) | Change |
|---|---|---|---|---|
| Anxiety | 9% | |||
| Confusion | -22% | |||
| Nausea | -36% | |||
| Motor Impairment | -76% | |||
| Muscle Tension | — | -81% | ||
| Memory Suppression | — | +15% | ||
| Jaw Clenching | -41% | |||
| Sweating | — | — | 0% | |
| Increased Heart Rate | — | -56% | ||
| Headache | — | — | 0% | |
| Psychosis | — | — | 0% | |
| Seizure | — | — | 0% |
Positive Effects
| Effect | Common (n=29) | Strong (n=27) | Heavy (n=67) | Change |
|---|---|---|---|---|
| Focus Enhancement | -48% | |||
| Music Enhancement | -8% | |||
| Color Enhancement | -28% | |||
| Euphoria | +34% | |||
| Empathy | +25% | |||
| Stimulation | -2% | |||
| Tactile Enhancement | +37% | |||
| Introspection | +12% | |||
| Body High | +88% | |||
| Creativity Enhancement | — | -34% |
Risk Escalation
Sentiment AnalysisAverage frequency of positive vs adverse effects across dose tiers (Intramuscular)
View effect breakdown
Adverse Effects
| Effect | Strong (n=16) | Heavy (n=26) | Change |
|---|---|---|---|
| Anxiety | +31% | ||
| Confusion | +104% | ||
| Nausea | -17% | ||
| Memory Suppression | +84% | ||
| Motor Impairment | +23% | ||
| Jaw Clenching | — | 0% | |
| Muscle Tension | — | 0% | |
| Psychosis | — | 0% |
Positive Effects
| Effect | Strong (n=16) | Heavy (n=26) | Change |
|---|---|---|---|
| Color Enhancement | -38% | ||
| Music Enhancement | -11% | ||
| Euphoria | -38% | ||
| Empathy | -38% | ||
| Focus Enhancement | +35% | ||
| Stimulation | -7% | ||
| Tactile Enhancement | 7% | ||
| Introspection | -23% | ||
| Body High | — | 0% |
Dosage Distribution
Dose distribution from experience reports
Oral
Insufflated
Intramuscular
Intravenous
Real-World Dose Distribution
62K DosesFrom 830 individual dose entries
Rectal (n=32)
Insufflated (n=297)
Oral (n=29)
Intravenous (n=29)
Intramuscular (n=124)
Smoked (n=7)
Sublingual (n=5)
Common Combinations
Most co-occurring substances in experience reports
Form / Preparation
Most common forms and preparations reported
Body-Weight Dosing
Dose relative to body weight from reports with weight data
Unknown
Oral
Insufflated
Intramuscular
Intravenous
Redose Patterns
Redosing behavior across 551 reports
Legal Status
| Country | Status | Notes |
|---|---|---|
| Australia | Schedule 8 | Possession, manufacture, or supply without authority is illegal. Classified as a controlled drug requiring strict regulation. |
| Austria | Prescription only (NR medication) | Legal for medical and veterinary use. Repeated dispense prohibited. Illegal when sold, possessed, or produced without a prescription under the Neue-Psychoaktive-Substanzen-Gesetz (NPSG). |
| Belgium | Prescription only | Legal for medical and veterinary use. Possession without prescription can result in arrest. |
| Brazil | Controlled (veterinary) | Legal for veterinary use only. Illegal when sold or possessed for human use. |
| Cambodia | Controlled | Not legal to possess without a prescription. Some pharmacies may sell ketamine, though most consider it forbidden. |
| Canada | Schedule I (CDSA) | Controlled under the Controlled Drugs and Substances Act as an analogue of phencyclidine (PCP). Sale, possession, and production are illegal unless authorized for medical, scientific, or industrial purposes. |
| China | Schedule II | Classified as a class II psychiatric drug. Trade is limited to licensed wholesalers and retail sales are prohibited. |
| Croatia | Controlled | Possession and distribution regulated under national drug legislation. |
| Czech Republic | Schedule IV (List 7) | Available exclusively with a prescription under Nařízení vlády č. 463/2013 Sb. Sales and distribution controlled under the Medicines Act. |
| Denmark | Controlled | Illegal except for scientific and medicinal uses as of February 8, 2008. |
| France | Schedule IV (Narcotic) | Listed as a narcotic in Annexe IV of the Liste des substances classées comme stupéfiants. Injectable preparations classified as Médicine - List I and subject to strict controls. |
| Germany | Prescription only (Anlage 1 AMVV) | Available by prescription for medical and veterinary use. Illegal when sold or possessed without a prescription. |
| Hong Kong | Schedule I | Classified as a dangerous drug with strict controls on possession, manufacture, and distribution. |
| India | Unscheduled | Not listed under the Narcotic Drugs and Psychotropic Substances Act, 1985. Reportedly available over-the-counter in many pharmacies. |
| Italy | Tabella I | Listed in Tabella I of Tabelle delle sostanze stupefacenti e psicotrope. Illegal to possess, purchase, or sell. |
| Japan | Narcotic | Classified as a narcotic under the Narcotic and Psychotropic Drugs Control Act (麻薬及び向精神薬取締法). |
| Luxembourg | Prohibited | Prohibited substance for recreational use under national drug legislation. |
| Malaysia | Illegal | Controlled under Section 39b of the Dangerous Drugs Act. Possession and sale are illegal. |
| Mexico | Category 3 | Classified under Mexico's General Health Law as having therapeutic value but constituting a problem for public health. Acquisition restricted to licensed veterinarians only under Medicines Administration Regulations. |
| Netherlands | Unscheduled (medication) | 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. |
| New Zealand | Class C | Reclassified as a Class C substance in February 2008, the same category as cannabis and codeine. |
| Norway | Class A | Classified as a Class A drug since 1999. Sold under the brand name Ketalar for authorized medical use. |
| Poland | Controlled | Illegal to possess, manufacture, and sell except for authorized medical purposes. |
| Singapore | Class A | 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. |
| Slovakia | Schedule II | Added to Schedule II (Grade 2) in October 2009, aligned with the 1971 United Nations Convention on Psychotropic Substances. |
| South Korea | Controlled | Controlled substance as of January 2005. Possession and sale are illegal. |
| Spain | Schedule IV | Classified as a Schedule IV substance under Spanish drug control legislation. |
| Sweden | Schedule IV | Scheduled as of July 1, 2005 following increased reports of recreational misuse. |
| Switzerland | Controlled (Verzeichnis B) | Specifically named under Verzeichnis B. Possession or handling without a license is illegal. Medicinal use is permitted. |
| Taiwan | Schedule III | Controlled under national narcotics legislation with restrictions on possession and distribution. |
| Turkey | Green prescription only | Available only with a 'green prescription' designation. Illegal when sold or possessed without a prescription. |
| United Kingdom | Class B | Reclassified as a Class B drug under the Misuse of Drugs Act 1971 on June 10, 2014. Previously classified as Class C from January 1, 2006. Prior to 2006, possession was legal though sales required licensing. |
| United States | Schedule III | Emergency scheduled by the DEA on August 12, 1999. Previously unscheduled with FDA-regulated sales. Possession without prescription or license is illegal. Esketamine nasal spray (Spravato) was FDA-approved in March 2019 for treatment-resistant depression under restricted distribution. |
References
Data Sources
Cited References
- Bluelight: How often can you safely do Ketamine
- Bluelight: Ketamine Tolerance
- Bluelight: Ketamine usage frequency dosage breaks
- Bluelight: Recommended dose of Ketamine (S+) isomer
- Bluelight: What counts as frequent ketamine use
- Global Drug Survey - Welcome to the K-hole
- Hi-Ground - Ketamine harm reduction sheet
- PMC: Ketamine-Associated Ulcerative Cystitis
- PMC: Ketamine Tolerance in Rats
- PulmCrit - The ketamine-tolerant patient
- Reddit: r/ketamine - Tolerance FAQ
- StatPearls - Ketamine
- The Psychedelic Society - Ketamine Harm Reduction
- TripSit: Drug Combination Chart
- People Magazine – severe cystitis from chronic use