About cotrimoxazole
Sulfonamide antibiotic combination
Used for
- Treats certain bacterial infections, including urinary and respiratory infections.
- Treats or prevents Pneumocystis pneumonia in people at increased risk.
Usual adult dose
Common infections: one standard tablet twice daily; dose and duration depend on infection and kidney function.
Usual dose in children
Used in children for selected infections; dose is based on body weight and infection.
Common side effects
- Nausea, vomiting, or loss of appetite
- Rash or itching
- Increased sensitivity to sunlight
- Changes in blood counts or potassium levels
Important warnings
- Rare severe skin reactions can occur; seek urgent care for blistering or peeling rash.
- Avoid or use only with specialist guidance in severe sulfonamide allergy.
- Kidney disease, liver disease, and folate deficiency may increase risks.
- Not effective against viral infections; inappropriate use promotes antibiotic resistance.
Pregnancy
Use only when clearly needed and prescribed; risks depend on pregnancy stage and infection.
Breastfeeding
Usually compatible for healthy, full-term infants, but may be unsuitable for premature, jaundiced, or ill infants.
Interactions
- Warfarin: may increase bleeding risk.
- Methotrexate: may increase toxicity.
- ACE inhibitors or potassium-sparing medicines: may raise potassium.
- Phenytoin: may increase phenytoin levels.
AI-generated from general medical knowledge, not from this product's official leaflet. It may be incomplete or out of date. Not medical advice — ask a pharmacist or doctor before making any decision.