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Open Dose Calculator →Cotrimoxazole
Trimethoprim-Sulfamethoxazole
💊 Used for: UTIs, PCP prophylaxis, otitis media
Formulation
Suspension
200mg SMX/40mg TMP per 5ml
Dose Range
2–4 mg/kg
Max Daily
16 mg/kg
Frequency
Every 12 hours
Max Single
160 mg
Route: Oral
Dose by Child Weight
Based on formulation: 200mg SMX/40mg TMP per 5ml
| Child's Weight | Dose (mg) | Dose (ml) | Max Daily Dose (mg) |
|---|---|---|---|
| 5 kg | 10–20 mg | 0.3–0.5 ml | ≤ 80 mg |
| 6 kg | 12–24 mg | 0.3–0.6 ml | ≤ 96 mg |
| 7 kg | 14–28 mg | 0.3–0.7 ml | ≤ 112 mg |
| 8 kg | 16–32 mg | 0.4–0.8 ml | ≤ 128 mg |
| 9 kg | 18–36 mg | 0.5–0.9 ml | ≤ 144 mg |
| 10 kg | 20–40 mg | 0.5–1.0 ml | ≤ 160 mg |
| 12 kg | 24–48 mg | 0.6–1.2 ml | ≤ 192 mg |
| 15 kg | 30–60 mg | 0.8–1.5 ml | ≤ 240 mg |
| 18 kg | 36–72 mg | 0.9–1.8 ml | ≤ 288 mg |
| 20 kg | 40–80 mg | 1.0–2.0 ml | ≤ 320 mg |
| 25 kg | 50–100 mg | 1.3–2.5 ml | ≤ 400 mg |
| 30 kg | 60–120 mg | 1.5–3.0 ml | ≤ 480 mg |
* Always verify with your doctor. doses are approximate and may vary based on condition and formulation.
⚠️ Important Warnings
- •Monitor for rash
- •Check for G6PD deficiency
- •May cause photosensitivity
Possible Side Effects
- •Nausea, vomiting, skin rash
- •Hyperkalemia (especially in HIV)
- •Bone marrow suppression
- •Stevens-Johnson syndrome (rare)
- •Hepatotoxicity
- •Asymptomatic hyperbilirubinemia
💡 Use the DoseCare Calculator for interactive dose calculations tailored to your child's exact weight and formulation.
DoseCare is a decision support tool only. Always verify doses with a qualified healthcare provider.