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Sulfamethoxazole-Trimethoprim

National Institute of Allergy and Infectious Diseases (NIAID) · FDA-approved active Small molecule

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

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

At a glance

Generic nameSulfamethoxazole-Trimethoprim
SponsorNational Institute of Allergy and Infectious Diseases (NIAID)
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 synthesis of dihydrofolate, while trimethoprim inhibits dihydrofolate reductase, blocking the conversion of dihydrofolate to tetrahydrofolate. Together, they create a synergistic effect that disrupts bacterial nucleotide synthesis and cell division. This combination is bactericidal against a broad range of gram-positive and gram-negative bacteria.

Approved indications

Common side effects

Key clinical trials

Primary sources

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

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