Pediatric Dosing for Ibuprofen and Paracetamol
For paracetamol (acetaminophen), administer 10-15 mg/kg per dose every 4-6 hours (maximum 60 mg/kg/day or 5 doses in 24 hours), and for ibuprofen, administer 10 mg/kg per dose every 6-8 hours (maximum 40 mg/kg/day), with paracetamol preferred for infants under 6 months and both medications showing equivalent safety and efficacy in older children. 1, 2
Paracetamol (Acetaminophen) Dosing
Standard Dosing Guidelines
- Dose: 10-15 mg/kg per dose, administered every 4-6 hours 1, 2
- Maximum daily dose: 60 mg/kg/day, not to exceed 5 doses in 24 hours 1, 2
- Route: Oral syrup is preferred over rectal suppositories due to more rapid and consistent absorption 1
Age-Specific Considerations
- Infants under 3 months: Paracetamol is the only recommended analgesic at 15 mg/kg per dose 1
- Infants under 6 months: Paracetamol remains first-line as ibuprofen is not recommended in this age group 1
- All pediatric ages: Paracetamol is indicated across all age groups, unlike NSAIDs which have age restrictions 3
Clinical Evidence
The 15 mg/kg dose demonstrates superior efficacy compared to older subtherapeutic doses of ≤10 mg/kg, showing comparable effectiveness to NSAIDs when dosed appropriately 3. Paracetamol at 15 mg/kg has a tolerability profile similar to placebo and shows lower risk of adverse events compared to NSAIDs when used repetitively over consecutive days 3.
Ibuprofen Dosing
Standard Dosing Guidelines
- Dose: 10 mg/kg per dose, administered every 6-8 hours 1, 2, 4
- Maximum daily dose: 40 mg/kg/day, not to exceed 3 doses in 24 hours 2, 4
- Maximum single dose: 600 mg per dose 4
Age and Weight-Specific Restrictions
- Not recommended: Infants under 6 months of age 1
- Children 6 months to 9 years: 10 mg/kg every 8 hours 4
- Children weighing >40 kg: Use adult dosing 1, 4
Clinical Evidence
The effective dose range is 7.5-10 mg/kg, with maximum temperature reduction occurring 3-4 hours after administration 5. Ibuprofen (5-10 mg/kg) demonstrates superior antipyretic efficacy compared to acetaminophen (10-15 mg/kg) at 2,4, and 6 hours post-treatment, though analgesic efficacy is comparable 6.
Comparative Efficacy and Safety
Pain Relief
Both medications show comparable efficacy for moderate to severe pain when dosed appropriately (ibuprofen 4-10 mg/kg vs acetaminophen 7-15 mg/kg), with no significant difference at 2 or 4 hours post-dose 6. Both paracetamol and ibuprofen are more effective than placebo for reducing acute pain symptoms in children 7.
Fever Reduction
Ibuprofen demonstrates superior antipyretic effect compared to paracetamol, with weighted effect sizes of 0.19,0.31, and 0.33 at 2,4, and 6 hours respectively 6. However, both medications are effective for fever management when dosed correctly 3.
Safety Profile
- Paracetamol: Remarkably well tolerated with few side effects at recommended doses; safer in overdose than aspirin but hepatotoxic at >10 times the recommended dose 8
- Ibuprofen: Better tolerated by children than adults; safer in overdose than paracetamol and aspirin 5
- No difference in adverse events: No evidence that either drug differs from the other or placebo in incidence of minor or major harm 6
Alternating Medications
When both medications are needed for breakthrough fever or pain:
- Stagger timing: Give paracetamol every 4-6 hours and ibuprofen every 6-8 hours, with medications administered every 3-4 hours alternating between the two 1
- Avoid simultaneous administration: Give separately rather than simultaneously unless breakthrough symptoms require combination therapy 2
Critical Safety Warnings
Maximum Dose Limits
- Paracetamol: Never exceed 60 mg/kg/day or 5 doses in 24 hours 1, 2
- Ibuprofen: Never exceed 40 mg/kg/day or 30 mg/kg/day per some guidelines 2, 4
Toxicity Prevention
- Counsel parents to avoid all other products containing paracetamol, including over-the-counter cold remedies, as concurrent use can lead to inadvertent overdose 2
- Chronic overdosing: Exposures greater than 140 mg/kg/day for several days carry risk of serious hepatotoxicity with paracetamol 8
Route Considerations
Rectal paracetamol should be used cautiously due to erratic absorption, which may result in inadequate analgesia or risk of accumulation with repeated dosing 1. Oral formulations provide more consistent and rapid absorption 1.