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Sulfamethoxazole Trimethoprim Combination

Baylor Research Institute · FDA-approved active Small molecule

Sulfamethoxazole-trimethoprim is a fixed-dose combination antibiotic that inhibits bacterial folate synthesis by blocking dihydropteroate synthase and dihydrofolate reductase, respectively.

Sulfamethoxazole-trimethoprim is a fixed-dose combination antibiotic that inhibits bacterial folate synthesis by blocking dihydropteroate synthase and dihydrofolate reductase, respectively. Used for Urinary tract infections, Pneumocystis jirovecii pneumonia (PCP) prophylaxis and treatment, Bacterial infections (various gram-positive and gram-negative organisms).

At a glance

Generic nameSulfamethoxazole Trimethoprim Combination
Also known asBACTRIM
SponsorBaylor Research Institute
Drug classSulfonamide-dihydrofolate reductase inhibitor combination
TargetDihydropteroate synthase; Dihydrofolate reductase
ModalitySmall molecule
Therapeutic areaInfectious Disease
PhaseFDA-approved

Mechanism of action

Sulfamethoxazole is a sulfonamide that inhibits dihydropteroate synthase, preventing the formation of dihydrofolate. Trimethoprim inhibits dihydrofolate reductase, blocking the conversion of dihydrofolate to tetrahydrofolate. Together, they create a synergistic effect by sequentially blocking bacterial folate metabolism, which is essential for nucleotide synthesis and bacterial growth.

Approved indications

Common side effects

Key clinical trials

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

SourceUsed for
ClinicalTrials.govTrial enrolment, design, endpoints, results

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