Acetaminophen Dosing for an 8-Month-Old Infant
The recommended acetaminophen dose for an 8-month-old infant is 10-15 mg/kg every 4-6 hours as needed, not to exceed 5 doses (60 mg/kg) in 24 hours.
Dosing Guidelines
Standard Dosing
- Dose range: 10-15 mg/kg per dose 1, 2
- Frequency: Every 4-6 hours as needed
- Maximum daily doses: 5 doses in 24 hours
- Maximum daily amount: 60 mg/kg/day 2
Weight-Based Calculation
For an 8-month-old infant, calculate the dose based on the infant's weight:
- For a 7 kg infant: 70-105 mg per dose
- For an 8 kg infant: 80-120 mg per dose
- For a 9 kg infant: 90-135 mg per dose
Administration Considerations
Formulation Options
- Oral liquid: Most appropriate for infants
- Infant drops (concentrated): 80 mg/0.8 mL
- Children's liquid: 160 mg/5 mL
- Rectal suppositories: Alternative if oral route not possible
- Available in various strengths (80 mg, 120 mg)
Important Safety Points
- Measure accurately: Use the measuring device provided with the medication
- Avoid household spoons: They provide inconsistent dosing 3
- Check concentration: Different formulations have different concentrations
- Record doses: Note the time and amount of each dose given
Clinical Pearls
- Weight-based dosing is more accurate than age-based dosing 3
- Underdosing is common and may result in inadequate fever control or pain relief 3
- Overdosing can lead to hepatotoxicity; single ingestions >10 times the recommended dose are potentially toxic 2
- Chronic dosing >140 mg/kg/day for several days carries risk of serious toxicity 2
- The antipyretic effect of acetaminophen typically lasts 4-6 hours 4
When to Seek Medical Attention
- If fever persists >3 days
- If fever is >102.2°F (39°C) in an infant under 3 months
- If the infant appears unusually irritable, lethargic, or has other concerning symptoms
- If you're unsure about the correct dosing
Using the recommended weight-based dosing approach ensures both safety and efficacy for fever reduction and pain relief in an 8-month-old infant.