Trimethoprim + Sulfamethoxazole

    Oral / IV
    Trimethoprim + Sulfamethoxazole
    Bactrim, Septrin 
    • Mechanism of Action
    • Trimethoprim inhibits the production of dihydrofolate reductase (DHFR), resulting in reduced conversion of dihydrofolic acid to active tetrahydrofolic acid - interfering with bacterial synthesis of nucleic acids. Sulfamethoxaole inhibits the production of dihydrofolate from para-aminobenzoic acid.
    • Microbiology
    • Active against most GI normal flora, the most common cause of UTI.Broad spectrum, including many aerobic gram-negative and gram-positive organisms.
    • No cover against pseudomonas.

Clinical Use

    • Indications
    • Otitis media
    • Lower respiratory tract infection
    • Genitourinary tract infections
    • Gastrointestinal infections
    • Skin / wound infections
    • Contraindications
    • Severe liver damage
    • Megaloblastic anaemia due to folate deficiency
    • Adverse Effects
    • Nausea / vomiting
    • Rash / pruritis
    • Elevated LFTs
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