Sulfamethoxazole

  • 3-(p-Aminophenylsulfonamido)-5-methylisoxazole
  • Benzenesulfonamide, 4-amino-N-(5-methyl-3-isoxazolyl)
  • Gantanol
  • N(1)-(5-Methyl-3-Isoxazolyl)sulfanilamide
  • 5-Methyl-3-sulfanilamidoisoxazole
  • Sulfamethalazole
Formula
C10H11N3O3S
Structure
Description
Crystals or white powder.
Uses
Medication.

Registry Numbers and Inventories.
CAS
723-46-6
EC (EINECS/ELINCS)
211-963-3
RTECS
WP0700000
RTECS class
Tumorigen; Drug; Human Data
Merck
12,9086
Beilstein/Gmelin
226453
Beilstein Reference
4-27-00-04685
Canada DSL/NDSL
DSL
US TSCA
Listed
Austrailia AICS
Listed
New Zealand
Listed
Korea ECL
Listed

Properties.
Formula
C10H11N3O3S
Formula mass
253.28
Melting point, °C
179
Boiling point, °C
482
Vapor pressure, mmHg
2E-9 (25 C)
Density
1.4777 g/cm3 (25 C)
Solubility in water
Soluble
pKa/pKb
5.81 (pKa)
Partition coefficient, pKow
0.89
Heat of fusion
33.8 kJ/mol
Heat of vaporization
47.7 kJ/mol

Hazards and Protection.
Storage
Commercially available sulfamethoxazole tablets and oral suspension should be protected from light and stored at a temperature less than 40C, preferably between 15-30C; freezing of the oral suspension should be avoided.
Handling
All chemicals should be considered hazardous. Avoid direct physical contact. Use appropriate, approved safety equipment. Untrained individuals should not handle this chemical or its container. Handling should occur in a chemical fume hood.
Protection
Chemical splash goggles in compliance with OSHA regulations are advised; however, OSHA regulations also permit other type safety glasses. Whre chemical resistant gloves. To prevent repeated or prolonged skin contact, wear impervious clothing and boots.
Respirators
Wear a NIOSH-approved half face respirator equipped with a combination filter cartridge, i.e. organic vapor/acid gas/HEPA (specific for organic vapors, HCl, acid gas, SO2 and a high efficiency particulate filter).
Small spills/leaks
If a spill of this chemical occurs, FIRST REMOVE ALL SOURCES OF IGNITION, then you should dampen the solid spill material with acetone and transfer the dampened material to a suitable container. Use absorbent paper dampened with acetone to pick up any remaining material. Seal your contaminated clothing and the absorbent paper in a vapor-tight plastic bag for eventual disposal. Solvent wash all contaminated surfaces with acetone followed by washing with a soap and water solution. Do not reenter the contaminated area until the Safety Officer (or other responsible person) has verified that the area has been properly cleaned.
Stability
Stable in air.

Fire.
Flash Point,°C
245
Fire fighting
Fires involving this compound should be controlled with a dry chemical, carbon dioxide or halon extinguisher.
Hazards
Flash point data for this compound are not available but it is probably non-flammable.

Health.
Exposure effects
headache, depression, and hallucinations have been reported with therapeutic use of sulfonamides. Coma and seizures were reported following a large overdose of sulfasalazine in one patient. Tremor occurred in one patient following a fixed-dose combination of trimethoprim/sulfamethoxazole.
   Ingestion
Nausea and vomiting are likely to occur.

First aid
 
   Ingestion
DO NOT INDUCE VOMITING. If the victim is conscious and not convulsing, give 1 or 2 glasses of water to dilute the chemical and IMMEDIATELY call a hospital or poison control center. Be prepared to transport the victim to a hospital if advised by a physician. If the victim is convulsing or unconscious, do not give anything by mouth, ensure that the victim's airway is open and lay the victim on his/her side with the head lower than the body. DO NOT INDUCE VOMITING. IMMEDIATELY transport the victim to a hospital.
   Inhalation
IMMEDIATELY leave the contaminated area; take deep breaths of fresh air. IMMEDIATELY call a physician and be prepared to transport the victim to a hospital even if no symptoms (such as wheezing, coughing, shortness of breath, or burning in the mouth, throat, or chest) develop. Provide proper respiratory protection to rescuers entering an unknown atmosphere. Whenever possible, Self-Contained Breathing Apparatus (SCBA) should be used.
   Skin
IMMEDIATELY flood affected skin with water while removing and isolating all contaminated clothing. Gently wash all affected skin areas thoroughly with soap and water. If symptoms such as redness or irritation develop, IMMEDIATELY call a physician and be prepared to transport the victim to a hospital for treatment.
   Eyes
First check the victim for contact lenses and remove if present. Flush victim's eyes with water or normal saline solution for 20 to 30 minutes while simultaneously calling a hospital or poison control center. Do not put any ointments, oils, or medication in the victim's eyes without specific instructions from a physician. IMMEDIATELY transport the victim after flushing eyes to a hospital even if no symptoms (such as redness or irritation) develop.

Transport.