Last reviewed 2026-04-23 · How we verify

SMZ/TMP

SMZ/TMP is a combination antibiotic that inhibits bacterial cell wall synthesis.

SMZ/TMP is a combination antibiotic that inhibits bacterial cell wall synthesis. Used for Community-acquired pneumonia, Urinary tract infections, Acute otitis media.

At a glance

Mechanism of action

SMZ (sulfamethoxazole) and TMP (trimethoprim) work synergistically to inhibit the synthesis of folic acid in bacteria, which is essential for their growth and replication. This leads to the death of the bacteria, effectively treating bacterial infections.

Approved indications

• Community-acquired pneumonia
• Urinary tract infections
• Acute otitis media
• Methicillin-resistant Staphylococcus aureus (MRSA) infections

Common side effects

• Nausea
• Vomiting
• Diarrhea
• Rash
• Headache

Key clinical trials

• Prevent TB: Choice Architecture for TPT Delivery (NA)
• 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)
• An Adaptive Multi-arm Trial to Improve Clinical Outcomes Among Children Recovering From Complicated SAM (PHASE3)
• 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)

Primary sources

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