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trimethoprim-sulfamethoxazole + metronidazole
This combination uses two antibiotics with different mechanisms—trimethoprim-sulfamethoxazole inhibits bacterial folate synthesis, while metronidazole disrupts DNA in anaerobic organisms—to provide broad-spectrum coverage against aerobic and anaerobic bacteria.
This combination uses two antibiotics with different mechanisms—trimethoprim-sulfamethoxazole inhibits bacterial folate synthesis, while metronidazole disrupts DNA in anaerobic organisms—to provide broad-spectrum coverage against aerobic and anaerobic bacteria. Used for Mixed aerobic-anaerobic bacterial infections, Intra-abdominal infections, Polymicrobial infections.
At a glance
| Generic name | trimethoprim-sulfamethoxazole + metronidazole |
|---|---|
| Sponsor | Halmstad County Hospital |
| Drug class | Antibiotic combination |
| Target | Bacterial dihydrofolate reductase, dihydropteroate synthase, and anaerobic DNA |
| Modality | Small molecule |
| Therapeutic area | Infectious Disease |
| Phase | FDA-approved |
Mechanism of action
Trimethoprim-sulfamethoxazole (TMP-SMX) blocks sequential steps in bacterial folate metabolism, inhibiting dihydrofolate reductase and dihydropteroate synthase, thereby preventing nucleotide synthesis. Metronidazole is a nitroimidazole that generates reactive intermediates in anaerobic organisms, causing DNA strand breaks and cell death. Together, they provide synergistic coverage for mixed aerobic-anaerobic infections.
Approved indications
- Mixed aerobic-anaerobic bacterial infections
- Intra-abdominal infections
- Polymicrobial infections
Common side effects
- Nausea and vomiting
- Metallic taste (metronidazole)
- Rash (TMP-SMX)
- Photosensitivity
- Peripheral neuropathy
- Hepatotoxicity
Key clinical trials
- Comparative Efficacy of Antibiotics for Small Intestine Bacterial Overgrowth in Bangladeshi Children (PHASE2)
- Comparing Oral Versus Parenteral Antimicrobial Therapy (PHASE4)
- Short-Term Use of Antibiotics and Adherence Level (NA)
- Patients Response to Early Switch To Oral:Osteomyelitis Study (EARLY_PHASE1)
- Efficacy of Oral Antibiotic Therapy Compared to Intravenous Antibiotic Therapy for Osteomyelitis (PHASE2)
- Home Based Child Care to Reduce Mortality and Malnutrition in Tribal Children of Melghat, India: CRCT (NA)
- Orally Administered Trimethoprim-sulfamethoxazole and Metronidazole as Prophylaxis of Infection Following Elective Colorectal Surgery (PHASE4)
- Antibiotics for the Treatment of Ulcerative Colitis (NA)
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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