Ceftriaxone Pediatric Dose Calculator
Weight-based ceftriaxone dosing for children — 50–80 mg/kg/dose · once daily (IV over 30 min or IM) · max 2 g/dose. Enter age and weight for the dose in mg and injection volume.
Pediatric dosing
Serious bacterial infection (sepsis, pneumonia, pyelonephritis) Hospital
Bacterial meningitis Hospital
Ceftriaxone dose chart by age and weight
Serious bacterial infection (sepsis, pneumonia, pyelonephritis). Weights are WHO/IAP reference medians for age — always dose on the measured weight.
| Age | Weight | Dose (mg) | 1 g vial + 10 mL water for injection (≈100 mg/mL) | Frequency |
|---|---|---|---|---|
| 15 days | 3.8 kg | 190 mg | 1.9 mL | Once daily (IV over 30 min or IM) |
| 1 month | 4.3 kg | 215 mg | 2.2 mL | Once daily (IV over 30 min or IM) |
| 3 months | 6.1 kg | 305 mg | 3.1 mL | Once daily (IV over 30 min or IM) |
| 6 months | 7.6 kg | 380 mg | 3.8 mL | Once daily (IV over 30 min or IM) |
| 9 months | 8.6 kg | 430 mg | 4.3 mL | Once daily (IV over 30 min or IM) |
| 1 year | 9.3 kg | 465 mg | 4.7 mL | Once daily (IV over 30 min or IM) |
| 18 months | 10.6 kg | 530 mg | 5.3 mL | Once daily (IV over 30 min or IM) |
| 2 years | 11.8 kg | 590 mg | 5.9 mL | Once daily (IV over 30 min or IM) |
| 3 years | 14.1 kg | 705 mg | 7.1 mL | Once daily (IV over 30 min or IM) |
| 4 years | 16.2 kg | 810 mg | 8.1 mL | Once daily (IV over 30 min or IM) |
| 5 years | 17.5 kg | 875 mg | 8.8 mL | Once daily (IV over 30 min or IM) |
| 6 years | 19 kg | 950 mg | 9.5 mL | Once daily (IV over 30 min or IM) |
| 8 years | 24.4 kg | 1220 mg | 12 mL | Once daily (IV over 30 min or IM) |
| 10 years | 31.1 kg | 1555 mg | 15.5 mL | Once daily (IV over 30 min or IM) |
| 12 years | 39.4 kg | 1970 mg | 19.5 mL | Once daily (IV over 30 min or IM) |
Strengths in the calculator
- 1 g vial + 10 mL water for injection (≈100 mg/mL) (Intravenous) — 250 mg and 500 mg vials reconstituted to the same 100 mg/mL give the same volumes.
Different strength on your bottle? Use “Different strength on the bottle?” under the result.
Safety
Contraindications and cautions
- Neonates with hyperbilirubinaemia, especially preterm — use cefotaxime.
- Neonates ≤28 days who need (or are expected to need) IV calcium-containing fluids — fatal precipitates reported.
- History of anaphylaxis to penicillins or cephalosporins.
Pregnancy and breastfeeding
Legacy FDA category B. No evidence of harm; use when clearly indicated.
Compatible with breastfeeding.
Clinical notes
Never mix or co-infuse with calcium-containing solutions (e.g. Ringer's lactate) in the same line.
Adult and adolescent (≥40 kg) dose
1–2 g — Once daily IV/IM (meningitis 2 g every 12 hours) (max 2 g per dose, 4 g per day).
Other names and brands
- India: Monocef, Oframax
- USA: Rocephin
- UK: Rocephin
Brand examples only — products and strengths vary by country. Always check the label.
Frequently asked questions
What is the ceftriaxone dose for children?
Serious bacterial infection (sepsis, pneumonia, pyelonephritis): 50–80 mg/kg/dose · once daily (IV over 30 min or IM) · max 2 g/dose. Usual duration: 7–14 days depending on infection. Always use the child's measured weight and check the strength on the bottle.
How many mL of 1 g vial + 10 mL water for injection (≈100 mg/mL) for an 11.8 kg child?
For serious bacterial infection (sepsis, pneumonia, pyelonephritis), an 11.8 kg child (about 2 years) needs 590 mg per dose — 5.9 mL of 1 g vial + 10 mL water for injection (≈100 mg/mL), once daily (IV over 30 min or IM). Recalculate with the child's actual weight.
From what age can ceftriaxone be given?
Age range in PediaRx: Birth – adult (hospital use). Each indication can have its own age and weight limits, shown with its regimen.
Is ceftriaxone safe in pregnancy?
Legacy FDA category B. No evidence of harm; use when clearly indicated.
Sources and editorial process
- BNF for Children — Ceftriaxone — NICE / BMJ Group / Royal Pharmaceutical Society
- Pocket Book of Hospital Care for Children, 2nd edition (2013) — World Health Organization
Dosing data last updated 2026-09-27. PediaRx is built and maintained by Dr. Shounak Pal, MBBS (Medical Officer, Government of West Bengal, India — founder and developer of PediaRx). Every regimen is encoded with explicit units, maximum doses and age/weight limits and is checked by automated tests before publication. Report an error: hello@pediarx.com.
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Clinical disclaimer: reference tool for qualified health professionals. Verify every dose against current guidance and the product label before prescribing.
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