Ketamine

Ketamine	Last updated: 10/09/2025
(Also known as: dl-ketamine)

GENERAL INFORMATION

Description

A rapid-acting, non-narcotic, non-barbiturate veterinary drug, usually used as the hydrochloride salt

Examples of veterinary uses

Used for anesthetic use and for chemical restraint

Examples of species treated

Cats; Dogs; Primates; Farmed livestock; Small domestic pets; Horses; Rodents

Approval status

VMR 2013/2033 approval status (GB/UK)

Approved - usually available as a prescription only medicine to be authorised by a veterinarian (POM-V)

EU Regulatory approval status

Approved

Chemical structure

Isomerism

Ketamine exhibits optical isomerism, specifically chirality, due to the presence of a chiral centre in its cyclohexanone ring structure giving enantiomers: S-ketamine (esketamine) and R-ketamine. S-ketamine binds more strongly to NMDA receptors, making it more potent and associated with fewer psychotomimetic side effects compared to R-ketamine.

Chemical formula

C₁₃H₁₆ClNO

Canonical SMILES

CNC1(CCCCC1=O)C2=CC=CC=C2Cl

Isomeric SMILES

No data

International Chemical Identifier key (InChIKey)

YQEZLKZALYSWHR-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C13H16ClNO/c1-15-13(9-5-4-8-12(13)16)10-6-2-3-7-11(10)14/h2-3,6-7,15H,4-5,8-9H2,1H3

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
ketamine	-
(-)-ketamine	-

General status

Veterinary substance type

Medicinal drug: anesthetic; dissociative hypnotic

Substance groups

Chlorobenzene

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Can block NMDA receptors and may interact with sigma receptors.

Molecular targets

[Glutamate receptor ionotropic, NMDA 3A, Antagonist], [Substance-P receptor, Antagonist], [D(2) dopamine receptor, Partial agonist], [Delta-type opioid receptor, Binder], [Sodium-dependent noradrenaline transporter]

CAS RN

6740-88-1

EC number

229-804-1

CIPAC number

US EPA chemical code

PubChem CID

Therapeutic Class

Anesthetics

ATCvet Code

QN01AX03

Controlled Drug?

UK: Class B, Schedule 2

Regulation 37/2010 MRL Classification

Molecular mass

337.73

PIN (Preferred Identification Name)

(RS)-2-(2-Chlorophenyl)-2-(methylamino)cyclohexanone

IUPAC name

(RS)-2-(2-Chlorophenyl)-2-(methylamino)cyclohexanone

CAS name

2-(2-Chlorophenyl)-2-(methylamino)cyclohexanone

Forever chemical

Other status information

Relevant Environmental Water Quality Standards

Physical state

Commercial

Property

Value

Availability status

Current

Introduction & key dates

1962, first synthesised; 1969, patented for animal use

Example manufacturers & suppliers of products using this active now or historically

Chanelle Pharma
Pfizer Animal Health
Dechra Pharmaceuticals
Le Vet Beheer B.V.
Vetoquinol UK Ltd

Example products using this active

Anaestamine Solution for Injection
Ketabel Solution for Injection
Narketan-10 Solution for Injection

Formulation and application details

Formulated as solutions for injection

Commercial production

Ketamine is synthesised through a multi-step chemical process starting with cyclohexanone, which reacts with 2-chlorophenyl magnesium bromide (a Grignard reagent) to form 1-(2-chlorophenyl)cyclohexanol. This intermediate undergoes dehydration using an acidic ionic liquid to yield 1-(2-chlorophenyl)cyclohexene, which is then oxidised to produce a hydroxy ketone compound. The next step involves imination with methylamine, forming an imine intermediate that is thermally rearranged to generate the final ketamine molecule.

Impact on climate of production and use

Published GHG data is not available for most pharmaceuticals. However, according to industry, global averages suggest producing 1 kg of a typical active pharmaceutical ingredient can range from 10 to 100 kg CO₂e for small molecule drugs and potentially up to 1000 kg CO₂e for complex biologicals such as vaccines, depending on the drug type, its formulation, complexity of synthesis, solvent recovery, and energy sources used.

ENVIRONMENTAL FATE

Property

Value

Source; quality score; and other information

Interpretation

Solubility - In water at 20 °C (mg l⁻¹)

2800

High

Solubility - In organic solvents at 20 °C (mg l⁻¹)

Melting point (°C)

Boiling point (°C)

Degradation point (°C)

Flashpoint (°C)

Octanol-water partition coefficient at pH 7, 20 °C

1.51 X 10⁰²

Calculated

Log P

2.18

Low

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

7.5

Vapour pressure at 20 °C (mPa)

Henry's law constant at 25 °C (Pa m³ mol⁻¹)

Volatilisation as max % of applied dose lost

From plant surface

From soil surface

Maximum UV-vis absorption L mol⁻¹ cm⁻¹

Surface tension (mN m⁻¹)

Refractive Index

Environmental release

Degradation

Property

Value

Source; quality score; and other information

Interpretation

Soil degradation (days) (aerobic)

DT₅₀ (typical)

DT₅₀ (lab at 20 °C)

DT₅₀ (field)

DT₉₀ (lab at 20 °C)

DT₉₀ (field)

Note

Manure DT₅₀ (days)

Aqueous photolysis DT₅₀ (days) at pH 7

Value

Note

Aqueous hydrolysis DT₅₀ (days) at 20 °C and pH 7

Value

Note

Water-sediment DT₅₀ (days)

Water phase only DT₅₀ (days)

Sediment phase only DT₅₀ (days)

Air degradation

As this parameter is not normally measured directly, a surrogate measure is used: ‘Photochemical oxidative DT₅₀’. Where data is available, this can be found in the Fate Indices section below.

Decay in stored produce DT₅₀

Soil adsorption and mobility

Property

Value

Source; quality score; and other information

Interpretation

Linear

K_d (mL g⁻¹)

K_oc (mL g⁻¹)

Notes and range

Freundlich

K_f (mL g⁻¹)

K_foc (mL g⁻¹)

¹/_n

Notes and range

pH sensitivity

Fate indices

Property

Value

Source; quality score; and other information

Interpretation

GUS leaching potential index

Bio-concentration factor

BCF (l kg⁻¹)

CT₅₀ (days)

Known metabolites

None

ECOTOXICOLOGY

Terrestrial ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

447

Rat

Moderate

Mammals - Short term dietary NOEL

(mg kg⁻¹)

(ppm diet)

Mammals - Chronic 21d NOAEL (mg kg⁻¹ bw d⁻¹)

Birds - Acute LD₅₀ (mg kg⁻¹)

Birds - Short term dietary (LC₅₀/LD₅₀)

Birds - Chronic 21d NOEL (mg kg⁻¹ bw d⁻¹)

Earthworms - Acute 14 day LC₅₀ (mg kg⁻¹)

Earthworms - Chronic NOEC, reproduction (mg kg⁻¹)

Soil micro-organisms

Collembola

Acute LC₅₀ (mg kg⁻¹)

Chronic NOEC (mg kg⁻¹)

Non-target plants

Vegetative vigour ER₅₀ (g ha⁻¹)

Seedling emergence ER₅₀ (g ha⁻¹)

Honeybees (Apis spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Unknown mode acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Chronic

Notes

Bumblebees (Bombus spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Mason bees (Osmia spp.)

Contact acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Oral acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg bee⁻¹)

Other bee species (1)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Other bee species (2)

Acute LD₅₀ (worst case from 24, 48 and 72 hour values - μg insect⁻¹)

Mode of exposure

Beneficial insects (Ladybirds)

Beneficial insects (Lacewings)

Beneficial insects (Parasitic wasps)

Beneficial insects (Predatory mites)

Beneficial insects (Ground beetles)

Aquatic ecotoxicology

Property

Value

Source; quality score; and other information

Interpretation

Temperate Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

Temperate Freshwater Fish - Chronic 21 day NOEC (mg l⁻¹)

Tropical Freshwater Fish - Acute 96 hour LC₅₀ (mg l⁻¹)

> 4.68

Danio rerio EC₅₀ Larva

Moderate

Temperate Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

Temperate Freshwater Aquatic invertebrates - Chronic 21 day NOEC (mg l⁻¹)

Tropical Freshwater Aquatic invertebrates - Acute 48 hour EC₅₀ (mg l⁻¹)

Aquatic crustaceans - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Acute 96 hour LC₅₀ (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, static, water (mg l⁻¹)

Sediment dwelling organisms - Chronic 28 day NOEC, sediment (mg kg⁻¹)

Aquatic Plants (free-floating, fonds growth, fresh) - 7 day (mg l⁻¹)

Aquatic plants (rooted, growth rate, fresh) - 14 day (mg l⁻¹)

Algae - Acute (growth rate, fresh; mg l⁻¹)

Algae - Chronic (growth rate, fresh; mg l⁻¹)

Mesocosm study data

NOEAEC mg l⁻¹

Marine bivalves

HUMAN HEALTH AND PROTECTION

General

Property

Value

Source; quality score; and other information

Interpretation

Threshold of Toxicological Concern (Cramer Class)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

447

Rat

Moderate

Mammals - Dermal LD₅₀ (mg kg⁻¹ body weight)

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

Intraperitoneal LD₅₀ = 400 mg kg⁻¹

Mouse

Intraveous LD₅₀ = 77 mg kg⁻¹

Mouse

ADI - Acceptable Daily Intake (mg kg⁻¹ bw day⁻¹)

ARfD - Acute Reference Dose (mg kg⁻¹ bw day⁻¹)

AAOEL - Acute Acceptable Operator Exposure Level (mg kg⁻¹ bw day⁻¹)

AOEL - Acceptable Operator Exposure Level - Systemic (mg kg⁻¹ bw day⁻¹)

Dermal penetration studies (%)

Dangerous Substances Directive 76/464

Exposure Routes

Public

Occupational

Mammalian dose elimination route and rate

Hepatic metabolism

Health issues

Specific human health issues

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

May increase heart rate and arterial blood pressure
May cause gastrointestinal irritation with nausea, vomiting and diarrhoea
May cause hallucinations, dream-like states and emergence delirium

Handling issues

Property

Value and interpretation

General

Will emit toxic fumes when heated to decomposition

CLP classification 2013

WHO Classification

Not listed (Not listed)

UN Number

Not regulated

Waste disposal & packaging

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

ketamine

French

German

Danish

Italian

cetamina

Spanish

Greek

Polish

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	10/09/2025
Contact:	aeru@herts.ac.uk
Please cite as:	Lewis, K.A., Tzilivakis, J., Warner, D. and Green, A. (2016) An international database for pesticide risk assessments and management. Human and Ecological Risk Assessment: An International Journal, 22(4), 1050-1064. DOI: 10.1080/10807039.2015.1133242