Tiletamine hydrochloride

Tiletamine hydrochloride	Last updated: 16/09/2025
(Not known by any other names)

GENERAL INFORMATION

Description

A veterinary anaesthetic which is related chemically to ketamine and commonly used in combination with zolazepam

Examples of veterinary uses

Anxiety management. Also used to control convulsions and to induce sedation for veterinary surgical procedures

Examples of species treated

Cats; Dogs; Polar bears

Approval status

VMR 2013/2033 approval status (GB/UK)

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

EU Regulatory approval status

Approved

Chemical structure

Isomerism

Tiletamine hydrochloride exhibits diastereomerism, due to the presence of a chiral centre at the carbon atom adjacent to the cyclohexanone ring. This chiral centre allows tiletamine to exist as two stereoisomers: (R)- and (S)-enantiomers. In commercial formulations like tiletamine is typically used as a racemic mixture.

Chemical formula

C₁₂H₁₈ClNOS

Canonical SMILES

CCNC1(CCCCC1=O)C2=CC=CS2.Cl

Isomeric SMILES

International Chemical Identifier key (InChIKey)

ZUYKJZQOPXDNOK-UHFFFAOYSA-N

International Chemical Identifier (InChI)

InChI=1S/C12H17NOS.ClH/c1-2-13-12(11-7-5-9-15-11)8-4-3-6-10(12)14;/h5,7,9,13H,2-4,6,8H2,1H3;1H

2D structure diagram/image available?

Yes

General status

Veterinary substance type

Medicinal drug, Anaesthetic, Sedative

Substance groups

Unclassified medicinal drug

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

NMDA receptor antagonist. It generates a so-called dissociative anaesthesia because it depresses certain cerebral regions whilst other regions, in particular the limbic system, remain active.

Molecular targets

[NMDA receptor, Antagonist]

CAS RN

14176-50-2

EC number

604-248-6

CIPAC number

US EPA chemical code

PubChem CID

26543

Therapeutic Class

Nervous system: Other general anaesthetics

ATCvet Code

QN02AX99

Controlled Drug?

Regulation 37/2010 MRL Classification

Molecular mass

259.8

PIN (Preferred Identification Name)

2-(ethylamino)-2-thiophen-2-ylcyclohexan-1-one;hydrochloride

IUPAC name

2-(ethylamino)-2-thiophen-2-ylcyclohexan-1-one;hydrochloride

CAS name

Forever chemical

Other status information

Relevant Environmental Water Quality Standards

Physical state

White crystalline solid

Related substances & organisms

zolazepam hydrochloride

ketamine

Commercial

Property

Value

Availability status

Current

Introduction & key dates

Circa 1965, first synthesised; 1980s, global agricultural use begins; 2015, first approvals China

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

Virbac Ltd

Example products using this active

Zoletil

Formulation and application details

Typically formulated as part of a combination injectable anaesthetic, most commonly paired with zolazepam hydrochloride

Commercial production

The production of tiletamine hydrochloride involves a multi-step synthetic pathway starting with the formation of cyclopentyl 2-thienyl ketone. This key intermediate is typically synthesized via a Friedel–Crafts acylation of thiophene with cyclopentanecarboxylic acid chloride, often catalysed by aluminium trichloride or graphite for improved yields. The ketone is then halogenated and reacted with an amine to form a substituted amino ketone. Through thermal rearrangement and reductive amination, the structure is refined into the active tiletamine base. Finally, the base is treated with hydrochloric acid to yield the hydrochloride salt.

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)

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

20000

Ethanol

Melting point (°C)

186

Boiling point (°C)

352.6

Degradation point (°C)

Flashpoint (°C)

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

Log P

Fat solubility of residues

Solubility

Data type

Density (g ml⁻¹)

Dissociation constant pKa) at 25 °C

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)

160

Mouse

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 dw soil)

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

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)

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)

160

Mouse

Moderate

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

Mammals - Inhalation LC₅₀ (mg l⁻¹)

Other Mammal toxicity endpoints

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

Metabolised in the liver, excreted via the kidneys

Health issues

Specific human health issues (hazard-based)

Carcinogen

Genotoxic

Endocrine disruptor

No data found

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

No data found

Eye irritant

Phototoxicant

No data found

General human health issues

May cause drowsiness

Handling issues

Property

Value and interpretation

General

IMDG Transport Hazard Code 6.1

CLP classification 2013

Health: H301, H361, H336

WHO Classification

Not listed (Not listed)

UN Number

UN2811

Waste disposal & packaging

Packaging group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

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English

tiletamine hydrochloride

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Record last updated:	16/09/2025
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