Pediatric Acetaminophen and Ibuprofen Dosing
For acetaminophen (Tylenol), give 10-15 mg/kg every 4-6 hours with a maximum of 60 mg/kg per day (not to exceed 5 doses in 24 hours), and for ibuprofen, give 10 mg/kg every 6-8 hours.
Acetaminophen (Tylenol) Dosing
Standard Dosing
- Dose: 10-15 mg/kg per dose 1, 2, 3
- Frequency: Every 4-6 hours 1, 2
- Maximum daily dose: 60 mg/kg per day 1
- Maximum number of doses: Up to 5 doses per 24 hours 4
Route-Specific Considerations
- Oral (syrup/liquid): 10-15 mg/kg every 6 hours 1
- Intravenous: Loading dose of 15-20 mg/kg, then 10-15 mg/kg every 6-8 hours 1
- Rectal: 20-40 mg/kg as a single loading dose (15 mg/kg if child weighs <10 kg) due to poor bioavailability from rectal route 1
Special Circumstances
- Post-vaccination fever prevention: 15 mg/kg at the time of vaccination, then every 4 hours for 24 hours 5
- Children with history of febrile seizures: 15 mg/kg prophylactically to reduce fever risk 5
Clinical Pearls
The oral syrup formulation is absorbed more rapidly and provides more consistent response compared to suppositories 6. A loading dose strategy (25 mg/kg initially, then 12.5 mg/kg every 6 hours) has been proposed for optimal antipyretic effect, though the simpler 10-15 mg/kg every 4-6 hours remains standard 6.
Ibuprofen Dosing
Standard Dosing
Important Safety Note
The dosing interval for ibuprofen is longer than acetaminophen—every 6-8 hours versus every 4-6 hours for acetaminophen 1. This is a critical distinction to prevent overdosing.
Common Pitfalls to Avoid
Underdosing and Overdosing
Studies show that 27% of parents give inadequate doses (<10 mg/kg) while 12% give excessive doses (≥20 mg/kg) of acetaminophen 4. Weight-based calculation is essential for proper dosing 2.
Frequency Errors
Some parents administer acetaminophen as frequently as every 2-3 hours (13% in one study), which risks toxicity, while others give it only every 8-24 hours (22%), which provides inadequate pain/fever control 4.
Age-Specific Cautions
- Infants <3 months: Acetaminophen is the only recommended analgesic; use 15 mg/kg if weight <10 kg 1
- Infants <6 months: Ibuprofen is generally not recommended in this age group (guideline focuses on children, not neonates) 1
Alternating Medications
While not explicitly detailed in the highest-quality guidelines reviewed, when alternating acetaminophen and ibuprofen:
- Give acetaminophen every 4-6 hours 1, 2
- Give ibuprofen every 6-8 hours 1
- Stagger timing so medications are given every 3-4 hours if both are needed
Toxicity Prevention
Maximum acetaminophen: Never exceed 60 mg/kg per day or 5 doses in 24 hours 1, 4. Overdosing can cause liver and kidney failure in children 7. Parents must be properly educated on accurate dosing to prevent both under- and over-administration 4.