Download SDS
CAS No.: 158966-92-8
Check the Montelukast product page for in-depth specifications, including solubility, stock solutions, MOA, and working concentrations.

Quick Safety Reference

🛡️ Hazard Overview

  • GHS Class: GHS07
  • Signal Word: Warning
  • Hazard Statements: H302; H312; H332

🧤 PPE Guidelines

  • Gloves: Chemical‑resistant gloves suggested
  • Eye Protection: Safety goggles suggested
  • Respirator: Dust respirator if dust occurs

❄️ Storage

  • Storage Temp: -20°C (-4°F) Keep dry

🚑 Emergency First Aid

  • For inhalation, skin, eye or ingestion exposure, please refer to full SDS Section 4.

GHS 16 Safety Standard Sections

Product identifier

  • Product Name: Montelukast
  • Catalog Number: S5783
  • CAS Number: 158966-92-8
  • IUPAC Name: Cyclopropaneacetic acid, 1-​[[[(1R)​-​1-​[3-​[(1E)​-​2-​(7-​chloro-​2-​quinolinyl)​ethenyl]​phenyl]​-​3-​[2-​(1-​hydroxy-​1-​methylethyl)​phenyl]​propyl]​thio]​methyl]​-

Relevant identified uses and uses advised against

  • Identified uses: For research and development use only; laboratory chemicals; manufacture of substances.
  • Uses advised against: Not for pharmaceutical, household, or other unapproved uses.

Details of the supplier

  • Company: Selleck Chemicals
  • TollFree: +1 877 796-6397
  • Tel: +1 832 582-8158
  • Fax: +1 832 582-8590

Emergency telephone number

  • Emergency phone #: +1 832 582-8158

2.1 GHS classification in accordance with 29 CFR 1910 (OSHA HCS):
Acute toxicity (oral): Category 4. H302
Acute toxicity (dermal): Category 4. H312
Acute toxicity (inhalation): Category 4. H332

2.2 GHS Label elements, including precautionary statements
Hazard Pictogram(s):
GHS07
Signal Word:
Warning
Hazard statement(s):
H302: Harmful if swallowed
H312: Harmful in contact with skin
H332: Harmful if inhaled
Precautionary statement(s):
Prevention:
P261: Avoid breathing dust/fume/gas/mist/vapors/spray.
P264: Wash hands thoroughly after handling.
P270: Do not eat, drink or smoke when using this product.
P271: Use only outdoors or in a well-ventilated area.
P280: Wear protective gloves/protective clothing/eye protection/face protection/hearing protection.
Response:
P301+P317: IF SWALLOWED: Get medical help.
P302+P352: IF ON SKIN: wash with plenty of water.
P304+P340: IF INHALED: Remove person to fresh air and keep comfortable for breathing.
P317: Get emergency medical help.
P321: Specific treatment (see information on this label and safety datasheet)).
P330: Rinse mouth.
P362+P364: Take off contaminated clothing and wash it before reuse.
Disposal:
P501: P501 Dispose of contents/ container to an approved waste disposal plant.

2.3 Other hazards
None.

3.1 Substances
Product name: Montelukast
CAS Number: 158966-92-8
PubChem CID: 5281040
Molecular formula: C35H36ClNO3S
Molecular weight: 586.2 g/mol
IUPAC name: 2-[1-[[(1R)-1-[3-[(E)-2-(7-chloroquinolin-2-yl)ethenyl]phenyl]-3-[2-(2-hydroxypropan-2-yl)phenyl]propyl]sulfanylmethyl]cyclopropyl]acetic acid

3.2 Mixtures
Not applicable (pure substance).

4.1 Description of first aid measures
Inhalation: Move to fresh air. Keep at rest in a position comfortable for breathing. Seek medical attention if symptoms persist.
Skin contact: Wash with plenty of soap and water. Remove contaminated clothing. Seek medical attention if irritation develops.
Eye contact: Rinse cautiously with water for several minutes. Remove contact lenses if present and easy to do. Continue rinsing. Seek medical attention.
Ingestion: Rinse mouth. Do NOT induce vomiting unless directed by medical personnel. Seek medical attention.

4.2 Most important symptoms and effects, both acute and delayed
See Section 11 (Toxicological Information).

4.3 Indication of any immediate medical attention and special treatment needed
Treat symptomatically. Contact a poison control center or physician for severe exposure.

5.1 Extinguishing media
Suitable: Water spray, dry chemical, carbon dioxide (CO2), alcohol-resistant foam.
Unsuitable: None known.

5.2 Specific hazards arising from the substance or mixture
Combustible. Heating may produce toxic fumes.

5.3 Advice for firefighters
Wear self-contained breathing apparatus (SCBA) and full protective clothing.
Fight fire from upwind. Cool containers with water spray until fire is extinguished.

6.1 Personal precautions, protective equipment and emergency procedures
Wear appropriate personal protective equipment (see Section 8).
Avoid breathing dust/vapor. Ensure adequate ventilation.
Evacuate personnel to safe areas. Keep people away from and upwind of spill.

6.2 Environmental precautions
Prevent product from entering drains, waterways, or soil.
Contain spill with inert absorbent material.

6.3 Methods and materials for containment and cleaning up
SRP: At the time of review, criteria for land treatment or burial (sanitary landfill) disposal practices are subject to significant revision. Prior to implementing land disposal of waste residue (including waste sludge), consult with environmental regulatory agencies for guidance on acceptable disposal practices.

7.1 Precautions for safe handling
Commercially available montelukast sodium film-coated and chewable tablets and oral granules should be stored at 25 °C and protected from light and moisture with exposure for short periods to temperatures of 15-30 °C permitted. When stored as directed, montelukast sodium film-coated and chewable tablets have an expiration date of 2 years after the date of manufacture.

7.2 Conditions for safe storage, including any incompatibilities
Commercially available montelukast sodium film-coated and chewable tablets and oral granules should be stored at 25 °C and protected from light and moisture with exposure for short periods to temperatures of 15-30 °C permitted. When stored as directed, montelukast sodium film-coated and chewable tablets have an expiration date of 2 years after the date of manufacture.
Store away from incompatible materials (see Section 10).
[Note: Specific storage temperature not available in public databases. Refer to supplier Certificate of Analysis (COA) for exact storage conditions.]

8.1 Exposure controls
8.1.1 Occupational exposure limits (OEL)
OSHA PEL: Not established.
ACGIH TLV: Not established.
NIOSH REL: Not established.
No occupational exposure limit values are established for this substance.
Use the lowest feasible exposure level (ALARA principle).

8.1.2 Appropriate engineering controls
Use in a well-ventilated area. Chemical fume hood recommended for powder handling.

8.2 Individual protection measures
8.2.1 Eye/face protection
Wear safety glasses with side shields.
8.2.2 Skin protection
Wear protective gloves. Recommended material: Nitrile rubber.
Wear suitable protective clothing (lab coat).
8.2.3 Respiratory protection
Use NIOSH-approved dust/mist respirator (N95 or higher) if ventilation is inadequate.
8.2.4 Thermal hazards
Not applicable.

9.1 Information on basic physical and chemical properties
a) Appearance: Solid
b) Odor: No data available
c) Odor threshold: No data available
d) pH: No data available
e) Melting point/freezing point: No data available
f) Initial boiling point and boiling range: No data available
g) Flash point: No data available
h) Evaporation rate: No data available
i) Flammability (solid, gas): No data available
j) Upper/lower flammability or explosive limits: No data available
k) Vapor pressure: No data available
l) Vapor density: No data available
m) Relative density: No data available
n) Water solubility: mixes with water (>100 mg/ml, 25 C)
o) Partition coefficient: n-octanol/water: Log P (n-octanol/water): 7.7
p) Auto-ignition temperature: No data available
q) Decomposition temperature: No data available
r) Viscosity: No data available
s) Explosive properties: No data available
t) Oxidizing properties: No data available

9.2 Other information
Topological Polar Surface Area (TPSA): 95.7 Ų
Complexity: 891

10.1 Reactivity
No specific reactivity hazards identified under normal handling conditions.

10.2 Chemical stability
Stable under recommended storage conditions.

10.3 Possibility of hazardous reactions
No hazardous reactions under normal conditions.

10.4 Conditions to avoid
Avoid heat, sparks, open flames, direct sunlight, and moisture.
Avoid strong oxidizing agents, strong acids, and strong bases.

10.5 Incompatible materials
Strong oxidizing agents, strong acids, strong bases.

10.6 Hazardous decomposition products
Thermal decomposition may produce: Carbon monoxide (CO), Carbon dioxide (CO₂), Nitrogen oxides (NOx), Sulfur oxides (SOx), Hydrogen chloride (HCl).
See also Section 5 (Fire-fighting measures) for combustion products.

11.1 Information on toxicological effects
Acute toxicity:
No acute toxicity data available.
Skin corrosion/irritation:
No data available.
Serious eye damage/eye irritation:
No data available.
Respiratory or skin sensitization:
No data available.
Germ cell mutagenicity:
No data available.
Carcinogenicity:
No data available.
Reproductive toxicity:
No data available.
Specific target organ toxicity (single exposure):
No data available.
Specific target organ toxicity (repeated exposure):
No data available.
Aspiration hazard:
No data available.

11.2 Additional information
No additional toxicological information available.

12.1 Toxicity
Montelukast's production and use as an antiasthmatic may result in its release to the environment through various waste streams. If released to air, an estimated vapor pressure of 4.1X10-21 mm Hg at 25 °C indicates montelukast will exist solely in the particulate phase in the atmosphere. Particulate-phase montelukast will be removed from the atmosphere by wet or dry deposition. Montelukast contains chromophores that absorb at wavelengths >290 nm and therefore may be susceptible to direct photolysis by sunlight. If released to soil, montelukast is expected to have no mobility based upon an estimated Koc of 6.0X10+7. The estimated pKa of montelukast is 4.3, indicating that this compound will primarily exist in the anion form in the environment and anions generally do not adsorb more strongly to soils containing organic carbon and clay than their neutral counterparts. Volatilization from moist soil surfaces is not expected to be an important fate process based upon the estimated pKa. Biodegradation data for montelukast were not availalble. If released into water, montelukast is expected to adsorb to suspended solids and sediment based upon its estimated Koc. An estimated pKa of 4.3 indicates montelukast will exist almost entirely in the anion form at pH values of 5 to 9 and therefore volatilization from water surfaces is not expected to be an important fate process. An estimated BCF of 3.2 suggests the potential for bioconcentration in aquatic organisms is low. Hydrolysis is not

12.2 Persistence and degradability
No data available.

12.3 Bioaccumulative potential
Log P (n-octanol/water): 7.7
Potential for bioaccumulation exists (Log P > 3).

12.4 Mobility in soil
No data available.

12.5 Results of PBT and vPvB assessment
PBT/vPvB assessment not available.

12.6 Other adverse effects
No other adverse ecological effects identified.

13.1 Waste treatment methods
Waste Treatment Methods: Waste material must be disposed of in accordance with national and local regulations. Leave chemicals in original containers and do not mix with other waste. Handle uncleaned containers in the same manner as the product itself.

14.1 UN number
Not regulated as dangerous goods (research quantities typically exempt).

14.2 UN proper shipping name
Not subject to transport regulations (small quantities for research use).

14.3 Transport hazard class(es)
Not classified as dangerous goods for transport (research quantities).

14.4 Packing group
Not applicable (not regulated as dangerous goods in typical research quantities).

14.5 Environmental hazards
Marine pollutant: No (not classified as environmentally hazardous per GHS).

14.6 Special precautions for user
Transport in original packaging. Ensure containers are tightly sealed.
For bulk or commercial quantities, consult applicable transport regulations (DOT, IATA, IMDG).

14.7 Transport in bulk according to Annex II of MARPOL 73/78 and the IBC Code
Not applicable.

15.1 Safety, health and environmental regulations/legislation specific for the substance or mixture
US EPA / TSCA: Not available in public databases.
EU ECHA / REACH: Not available in public databases.

SARA 302 Components:
No chemicals in this material are subject to the reporting requirements of SARA Title III, Section 302.
SARA 313 Components:
This material does not contain any chemical components with known CAS numbers that exceed the threshold (De Minimis) reporting levels established by SARA Title III, Section 313.
SARA 311/312 Hazards:
Acute (short-term) health hazard

Massachusetts Right To Know Components:
This material contains components subject to the Massachusetts Right to Know Act. See Section 2 for hazard classification.
Pennsylvania Right To Know Components:
This material contains components subject to the Pennsylvania Right to Know Act. See Section 2 for hazard classification.
New Jersey Right To Know Components:
This material contains components subject to the New Jersey Right to Know Act. See Section 2 for hazard classification.

California Prop. 65 Components:
This product does not contain any chemicals known to the State of California to cause cancer, birth defects, or any other reproductive harm.

Other regulatory listings:
- FDA Requirements: The Approved Drug Products with Therapeutic Equivalence Evaluations List identifies currently marketed prescription drug products, incl Montelukast sodium, approved on the basis of safety and effectiveness by FDA under sections 505 of the Federal Food, Drug, and Cosmetic Act. /Montelukast sodium/

15.2 Chemical safety assessment
A chemical safety assessment has not been carried out for this substance.
For research-use-only compounds, no CSA is required under REACH Annex I.

Revision Date: 2026/09/09
Further Information: The information provided is believed to be correct but is not exhaustive and should be used only as a guideline based on current knowledge. It does not represent a guarantee of the properties of the product. Selleck Chemicals Corporation and its Affiliates shall not be held liable for any damage resulting from handling or contact with the product.

Note: Technical data last updated: Sep 1, 2026.