Flunixin meglumine

Flunixin meglumine	Last updated: 14/09/2025
(Also known as: banamine; Sch 14714 meglumine)

GENERAL INFORMATION

Description

A non-steroidal anti-inflammatory drug (NSAID), analgesic, and antipyretic used in veterinary medicine

Examples of veterinary uses

Mainly used to treat skeletal and muscular disorders as well as colic

Examples of species treated

Horses; Cattle; Pigs

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

Flunixin meglumine exhibits stereoisomerism, specifically chirality, due to the presence of multiple chiral centres in its meglumine component. The active compound, flunixin, is a nonsteroidal anti-inflammatory drug with a relatively simple aromatic structure that itself is achiral. However, when flunixin is formulated as the meglumine salt, it is paired with meglumine (N-methylglucamine), a sugar alcohol derivative that contains five chiral centres at positions C2 through C6 of the hexane backbone. These centres are configured as (2R,3R,4R,5S) in the pharmaceutical-grade compound, giving the meglumine portion a defined stereochemistry that influences solubility, stability, and pharmacokinetics.

Chemical formula

C₂₁H₂₈F₃N₃O₇

Canonical SMILES

CC1=C(C=CC=C1NC2=C(C=CC=N2)C(=O)O)C(F)(F)F.CNCC(C(C(C(CO)O)O)O)O

Isomeric SMILES

CC1=C(C=CC=C1NC2=C(C=CC=N2)C(=O)O)C(F)(F)F.CNC[C@@H]([C@H]([C@@H]([C@@H](CO)O)O)O)O

International Chemical Identifier key (InChIKey)

MGCCHNLNRBULBU-WZTVWXICSA-N

International Chemical Identifier (InChI)

InChI=1S/C14H11F3N2O2.C7H17NO5/c1-8-10(14(15,16)17)5-2-6-11(8)19-12-9(13(20)21)4-3-7-18-12;1-8-2-4(10)6(12)7(13)5(11)3-9/h2-7H,1H3,(H,18,19)(H,20,21);4-13H,2-3H2,1H3/t;4-,5+,6+,7+/m.0/s1

2D structure diagram/image available?

Yes

Cambridge Crystallographic Data Centre diagrams

Common Name	Relationship	Link
flunixin	Parent
flunixin meglumine	-

General status

Veterinary substance type

Anagelsic, anti-inflammatory, Medicinal drug

Substance groups

Unclassified substance

Minimum active substance purity

Known relevant impurities

Substance origin

Synthetic

Mode of action

Works via the inhibition of cyclooxygenase, blocks synthesis of eicosanoids which are chemical mediators of inflammation

Molecular targets

[Prostaglandin G/H Synthase 2, Antagonist]

CAS RN

42461-84-7

EC number

255-836-0

CIPAC number

US EPA chemical code

PubChem CID

39212

Therapeutic Class

Musculo-skeletal system: Anti-inflammatory & antirheumatic products

ATCvet Code

QM01AG90

Controlled Drug?

Regulation 37/2010 MRL Classification

Allowed substance (Table 1: Bovine, Porcine, Equidae)

Molecular mass

491.5

PIN (Preferred Identification Name)

IUPAC name

(2R,3R,4R,5S)-6-(methylamino)hexane-1,2,3,4,5-pentol;2-[2-methyl-3-(trifluoromethyl)anilino]pyridine-3-carboxylic acid

CAS name

Forever chemical

Other status information

Relevant Environmental Water Quality Standards

Physical state

Clear liquid

Related substances & organisms

flunixin

Commercial

Property

Value

Availability status

Current

Introduction & key dates

Circa 1990s, introduced

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

Bimeda Animal Health Ltd
Emdoka
Krka d.d. Novo Mestro
MSD Animal Health UK Ltd

Example products using this active

Cronyxin Solution for Injection
Emdofluxin Solution for Injection
Flovuxin Solution for Injection
Resflor Solution for Injection

Formulation and application details

Usually supplied as a solution for injection or as a powder for preparation as a solution for injection

Commercial production

Flunixin meglumine is produced through a two-stage synthesis beginning with the formation of flunixin, a nonsteroidal anti-inflammatory compound. The process starts by reacting 2-chloronicotinic acid with 2-methyl-3-trifluoromethylaniline in an aqueous sodium hydroxide solution, often with a phase-transfer catalyst and an organic solvent like toluene. This mixture is stirred and heated at around 40–45 DegC for several hours, forming flunixin via nucleophilic aromatic substitution. After adjusting the pH and isolating the product through filtration and drying, the crude flunixin is then reacted with N-methylglucamine (meglumine) in isopropanol under reflux conditions for 0.5–1.5 hours. The resulting flunixin meglumine salt is then crystallised.

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)

Melting point (°C)

Boiling point (°C)

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)

> 53

Rat

High

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)

375

Colinus virginianus

Moderate

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)

> 46

Lepomis macrochirus

Moderate

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)

25.0

Daphnia magna

Moderate

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) (EC₅₀)

> 36

Unknown species

Low

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)

High (class III)

Mammals - Acute oral LD₅₀ (mg kg⁻¹)

> 53

Rat

High

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

Widely distributed throughout body tissues and fluids. Excretion via urine, bile and other gastrointestinal secretions.

Health issues

Specific human health issues (hazard-based)

Carcinogen

Genotoxic

Endocrine disruptor

; ; ; ;

No data found

Reproduction / development effects

Acetyl cholinesterase inhibitor

Neurotoxicant

No data found

Respiratory tract irritant

Skin irritant

Skin sensitiser

Eye irritant

Phototoxicant

No data found

General human health issues

May cause gastrointestinal problems
Possible liver and kidney toxicant

Handling issues

Property

Value and interpretation

General

IMDG Transport Hazard Class 6.1
Inccompatible with acids, bases, and oxidising agents

CLP classification 2013

Health: H302, H315, H318, H333, H373
Environment: H412

WHO Classification

Not listed (Not listed)

UN Number

UN2811

Waste disposal & packaging

Packaging Group III (minor danger)

Shelf-life, storage, stability and reactivity

TRANSLATIONS

Language

Name

English

flunixin meglumine

French

German

Danish

Italian

Spanish

Greek

Polish

Swedish

Hungarian

Dutch

Norwegian

Record last updated:	14/09/2025
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