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Sulfamethoxazole is a crystal or white powder with the chemical name N-(5-methyl-3-isoxazolyl)-4-aminobenzenesulfonamide. It is a sulfonamide bacteriostatic antibiotic that is effective against gram negative and positive bacteria such as Listeria monocytogenes and E.coli. It is mainly used in the treatment of bacterial infections such as urinary tract infections, bronchitis, and prostatitis. The structure is shown in fig. 1.

Structure of sulfamethoxazole

Fig. 1 Structure of sulfamethoxazole

Application in the treatment of bacterial infections

Sulfamethoxazole was introduced to the United States in 1961. It is now mostly used in combination with trimethoprim. The combination has been included on the WHO Model List of Essential Medicines as a first-choice to treat urinary tract infections.

  • Introduction of bacterial infections

Bacterial infections are any illness or condition caused by bacterial growth or toxicity. They may affect your skin, lungs, brain, blood and other parts of your body. Some common types of bacterial infections include food poisoning (gastroenteritis), skin, ear or sinus infections, sexually transmitted infections and urinary tract infections. In addition to skin infections, the main symptoms of other bacterial infections are often fever, chills, fatigue and headaches. Bacterial infections require prompt treatment and sulfamethoxazole is a quality drug candidate.

Introduction of bacterial infections
  • Mechanism of action

Sulfamethoxazole, a sulfanilamide, is a structural analog of para-aminobenzoic acid (PABA). It competes with PABA to bind to dihydropteroate synthetase and inhibits the conversion of PABA to dihydrofolic acid. Inhibition of this pathway ultimately prevents the synthesis of folate that is a critical role during DNA synthesis. Therefor, sulfamethoxazole can inhibit the growth and replication of bacteria by blocking DNA synthesis. In addition, the synthesis of folate does not occur in humans, that is, sulfamethoxazole only acts on bacteria and not on the human body.

  • Side effects

The most common side effects of sulfamethoxazole mainly include:

  • Allergic skin reactions: such as rash and urticaria.
  • Gastrointestinal disturbances: such as nausea, vomiting and anorexia.

Alfa Chemistry offers high quality sulfamethoxazole. Please feel free to contact us for APIs or technical services.