Clarithromycin Pediatric Dose Calculator
Weight-based clarithromycin dosing for children — 7.5 mg/kg/dose · every 12 hours · max 500 mg/dose. Enter age and weight for the dose in mg and syrup mL or tablets.
Pediatric dosing
Respiratory infection / atypical pneumonia
Clarithromycin dose chart by age and weight
Respiratory infection / atypical pneumonia. Weights are WHO/IAP reference medians for age — always dose on the measured weight.
| Age | Weight | Dose (mg) | Suspension 125 mg/5 mL | Suspension 250 mg/5 mL | Frequency |
|---|---|---|---|---|---|
| 1 month | 4.3 kg | 32.3 mg | 1.3 mL | 0.65 mL | Every 12 hours |
| 3 months | 6.1 kg | 45.8 mg | 1.8 mL | 0.92 mL | Every 12 hours |
| 6 months | 7.6 kg | 57 mg | 2.3 mL | 1.1 mL | Every 12 hours |
| 9 months | 8.6 kg | 64.5 mg | 2.6 mL | 1.3 mL | Every 12 hours |
| 1 year | 9.3 kg | 69.8 mg | 2.8 mL | 1.4 mL | Every 12 hours |
| 18 months | 10.6 kg | 79.5 mg | 3.2 mL | 1.6 mL | Every 12 hours |
| 2 years | 11.8 kg | 88.5 mg | 3.5 mL | 1.8 mL | Every 12 hours |
| 3 years | 14.1 kg | 105.8 mg | 4.2 mL | 2.1 mL | Every 12 hours |
| 4 years | 16.2 kg | 121.5 mg | 4.9 mL | 2.4 mL | Every 12 hours |
| 5 years | 17.5 kg | 131.3 mg | 5.3 mL | 2.6 mL | Every 12 hours |
| 6 years | 19 kg | 142.5 mg | 5.7 mL | 2.9 mL | Every 12 hours |
| 8 years | 24.4 kg | 183 mg | 7.3 mL | 3.7 mL | Every 12 hours |
| 10 years | 31.1 kg | 233.3 mg | 9.3 mL | 4.7 mL | Every 12 hours |
| 12 years | 39.4 kg | 295.5 mg | 12 mL | 5.9 mL | Every 12 hours |
Strengths in the calculator
- Suspension 125 mg/5 mL (Oral)
- Suspension 250 mg/5 mL (Oral)
- Tablet 250 mg (Oral — do not split)
- Tablet 500 mg (Oral — do not split)
Different strength on your bottle? Use “Different strength on the bottle?” under the result.
Safety
Contraindications and cautions
- QT prolongation; concurrent CYP3A4 substrates with narrow therapeutic index (e.g. some antiepileptics, colchicine).
Pregnancy and breastfeeding
Legacy FDA category C. Avoid, especially in the first trimester, unless benefit outweighs risk.
Present in breast milk; use with caution.
Clinical notes
Many drug interactions (strong CYP3A4 inhibitor). Taste disturbance is common.
Adult and adolescent (≥40 kg) dose
250–500 mg — Every 12 hours (max 500 mg per dose, 1 g per day).
Other names and brands
- India: Claribid
- UK: Klaricid
- USA: Biaxin
Brand examples only — products and strengths vary by country. Always check the label.
Frequently asked questions
What is the clarithromycin dose for children?
Respiratory infection / atypical pneumonia: 7.5 mg/kg/dose · every 12 hours · max 500 mg/dose. Usual duration: 5–14 days. Always use the child's measured weight and check the strength on the bottle.
How many mL of suspension 125 mg/5 mL for an 11.8 kg child?
For respiratory infection / atypical pneumonia, an 11.8 kg child (about 2 years) needs 88.5 mg per dose — 3.5 mL of Suspension 125 mg/5 mL, every 12 hours. Recalculate with the child's actual weight.
From what age can clarithromycin be given?
Age range in PediaRx: 1 month – adult. The calculator does not calculate a dose below 1 month. Each indication can have its own age and weight limits, shown with its regimen.
Is clarithromycin safe in pregnancy?
Legacy FDA category C. Avoid, especially in the first trimester, unless benefit outweighs risk.
Sources and editorial process
- BNF for Children — Clarithromycin — NICE / BMJ Group / Royal Pharmaceutical Society
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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