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Trimethoprim and sulfamethoxazole
Trimethoprim and sulfamethoxazole is a fixed-dose combination antibiotic that inhibits bacterial folate synthesis by blocking two sequential enzymes in the pathway.
Trimethoprim and sulfamethoxazole is a fixed-dose combination antibiotic that inhibits bacterial folate synthesis by blocking two sequential enzymes in the pathway. Used for Urinary tract infections, Pneumocystis jirovecii pneumonia (PCP) prophylaxis and treatment, Acute otitis media.
At a glance
| Generic name | Trimethoprim and sulfamethoxazole |
|---|---|
| Also known as | Septra®) |
| Sponsor | National Institute of Allergy and Infectious Diseases (NIAID) |
| Drug class | Sulfonamide antibiotic combination |
| Target | Dihydropteroate synthase and dihydrofolate reductase |
| Modality | Small molecule |
| Therapeutic area | Infectious Disease |
| Phase | FDA-approved |
Mechanism of action
Sulfamethoxazole inhibits bacterial dihydropteroate synthase, while trimethoprim inhibits dihydrofolate reductase. Together, they sequentially block the synthesis of dihydrofolate and tetrahydrofolate, which are essential cofactors for bacterial nucleotide synthesis. This synergistic dual inhibition is bactericidal against a broad spectrum of gram-positive and gram-negative bacteria.
Approved indications
- Urinary tract infections
- Pneumocystis jirovecii pneumonia (PCP) prophylaxis and treatment
- Acute otitis media
- Traveler's diarrhea
- Toxoplasmosis prophylaxis in immunocompromised patients
- Bacterial infections (respiratory, gastrointestinal, soft tissue)
Common side effects
- Rash
- Nausea
- Vomiting
- Diarrhea
- Headache
- Stevens-Johnson syndrome
- Hepatotoxicity
- Hyperkalemia
Key clinical trials
- A Study of LBP-EC01 in the Treatment of Acute Uncomplicated UTI Caused by Drug Resistant E. Coli (ELIMINATE Trial) (PHASE2)
- Testing a Novel Combination Treatment (Arm D) Versus Standard of Care for Intensive Phase Treatment for Mycobacterium Abscessus Pulmonary Disease in People With or Without Cystic Fibrosis in the Finding the Optimal Regimen for Mycobacterium Abscessus Treatment (FORMaT) Adaptive Platform Trial (PHASE2)
- Effects of Treatments on Atopic Dermatitis (PHASE2)
- Gram-Negative Bloodstream Infection Oral Antibiotic Therapy Trial (NA)
- Effect of S. Aureus Skin Decolonization on Disease Severity in Atopic Dermatitis Patients (PHASE4)
- Comparative Efficacy of Antibiotics for Small Intestine Bacterial Overgrowth in Bangladeshi Children (PHASE2)
- Oral Antimicrobial Treatment vs. Outpatient Parenteral for Infective Endocarditis (PHASE4)
- Low Dose Trimethoprim-Sulfamethoxazole for the Treatment of Pneumocystis Jirovecii Pneumonia (PHASE3)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
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