Pediatric Acetaminophen (Tylenol) Dosing
The recommended dose of acetaminophen for children is 10-15 mg/kg per dose, administered orally every 4-6 hours, with a maximum of 5 doses per day. 1, 2
Weight-Based Dosing Algorithm
- Calculate the dose: Multiply the child's weight in kilograms by 10-15 mg to determine the appropriate single dose 1, 2
- Dosing interval: Administer every 4-6 hours as needed for fever or pain 1, 2
- Maximum daily frequency: Do not exceed 5 doses in 24 hours 1
- Onset and duration: Expect rapid temperature reduction with maximum effect occurring approximately 3 hours after administration 2
Age-Based Dosing Considerations
- Infants under 3 months: Acetaminophen is the only recommended analgesic for this age group, but medical consultation is advised 3
- Children 6 months to 12 years: Use the weight-based calculation of 10-15 mg/kg per dose 1
- Adolescents 12 years and older: May receive 500-1000 mg per dose (adult dosing), but weight-based dosing remains appropriate 3
Special Clinical Situations
- Post-vaccination fever prevention: The CDC recommends acetaminophen can be given at the time of vaccination and every 4 hours for 24 hours 4
- Febrile seizure prophylaxis: The AAP supports using 15 mg/kg prophylactically in children with a history of febrile seizures 4
- Pain management in stable neurologic conditions: Acetaminophen is generally safe and preferred over NSAIDs per CDC guidance 4
Critical Dosing Pitfalls
- Underdosing is common: Studies show 27% of children receive inadequate doses (<10 mg/kg), resulting in poor fever control 5
- Overdosing risk: Approximately 12% of children receive excessive doses (≥20 mg/kg), which increases hepatotoxicity risk 5
- Formulation confusion: Two-thirds of parents use syrup while one-third use suppositories; oral suspension provides more consistent response than suppositories at equivalent doses 6
- Frequency errors: Some parents dose as frequently as every 2-3 hours (inappropriate) while others dose only every 8-24 hours (inadequate) 5
Loading Dose Strategy
For optimal antipyretic effect, consider an initial loading dose approach: 25 mg/kg as the first dose, followed by 12.5 mg/kg every 6 hours for maintenance 6. This regimen achieves therapeutic plasma concentrations (4-18 mg/L) more rapidly 6.
Safety Profile
Acetaminophen is one of the safest analgesic-antipyretics when used at recommended doses 1. However, overdosing or chronic overuse can lead to liver and kidney failure 3. The drug has a half-life of 1-3.5 hours in children 6.