Weight-Based Dosing: mg per Kilogram
Pediatric doses are calculated from body weight, not age brackets.
- 15 mg/kg: Acetaminophen dose (per dose, every 4–6 hr)
- 10 mg/kg: Ibuprofen dose (per dose, every 6–8 hr)
- 1000 mg: Acet. max single (ceiling dose cap)
- 400 mg: Ibu. max single (ceiling dose cap)
Why weight, not age
Placeholder: weight-based dosing improves accuracy across growth stages.
Acetaminophen: Onset and Duration
Acetaminophen relieves fever and pain with a moderate onset window.
- ~45 min: Onset (oral suspension)
- ~5 hr: Duration (per dose)
- ~1 hr: Peak plasma (time to Cmax)
- Hepatic: Metabolism (glucuronidation pathway)
Onset-duration curve shape
Placeholder: gradual rise, moderate plateau, steady decline.
Ibuprofen: Onset and Duration
Ibuprofen acts faster and lasts longer than acetaminophen.
- ~25 min: Onset (oral suspension)
- ~7 hr: Duration (per dose)
- ~1.5 hr: Peak plasma (time to Cmax)
- Hepatic/renal: Metabolism (CYP2C9 pathway)
Onset-duration curve shape
Placeholder: sharper rise, longer plateau, slower decline.
Safety Profiles Side by Side
Each drug carries distinct organ-system risk considerations.
- Hepatotoxicity: Acet. main risk (overdose concern)
- GI/renal: Ibu. main risk (with dehydration)
- 6 months: Age floor (Ibu.) (not for infants under)
- 0 months: Age floor (Acet.) (usable from birth)
Choosing between the two
Placeholder: pick based on fever severity, hydration, GI history.
Placeholder: always confirm dosing with a pediatrician or pharmacist.
The Alternating Dosing Controversy
Alternating acetaminophen and ibuprofen is common but debated.
- Mixed: Evidence quality (limited RCT support)
- Higher: Dosing error risk (complex schedules)
- Marginal gain: Fever reduction (vs single-agent)
- Caution: Guideline stance (varies by country)
Why clinicians disagree
Placeholder: benefit is small while confusion risk rises.
Placeholder: discuss alternating regimens with a clinician first.