What is the recommended dose of Motrin (ibuprofen) for a 4-year-old child weighing 38 pounds?

Ibuprofen Dosing for a 4-Year-Old Child Weighing 38 Pounds

The recommended dose of Motrin (ibuprofen) for a 4-year-old child weighing 38 pounds is 5-10 mg/kg per dose, which equals 85-170 mg per dose, given every 6-8 hours as needed, not to exceed 4 doses in 24 hours.

Dosage Calculation

For a child weighing 38 pounds (approximately 17.3 kg):

• Minimum dose: 5 mg/kg × 17.3 kg = 86.5 mg
• Maximum dose: 10 mg/kg × 17.3 kg = 173 mg

Practical Administration

• Children's Motrin/ibuprofen liquid typically comes in a concentration of 100 mg/5 mL
• Appropriate dose would be 4.5-8.5 mL per dose (rounded to practical volumes)
• Most commonly used dose is 7.5 mL (150 mg) for this weight

Dosing Schedule

• Give every 6-8 hours as needed for fever or pain
• Maximum of 4 doses in 24 hours
• Do not exceed 40 mg/kg/day (approximately 690 mg total daily for this child)

Efficacy Information

• Onset of action: 30-60 minutes
• Peak effect: 2-4 hours
• Duration of action: 6-8 hours
• Maximum fever reduction occurs 3-4 hours after administration 1

Safety Considerations

• Ibuprofen is generally well-tolerated in children and has been shown to be as safe as acetaminophen when used at appropriate doses 1
• Always use the measuring device provided with the medication
• Do not exceed recommended doses or frequency
• Use the lowest effective dose for the shortest duration needed
• Ensure child is well-hydrated when taking ibuprofen

Common Pitfalls to Avoid

1. Using adult formulations for children (higher concentration)
2. Confusing dosing between different medications (acetaminophen vs. ibuprofen)
3. Using household spoons instead of proper measuring devices
4. Exceeding the maximum daily dose (reported in 11% of children in some studies 2)
5. Administering too frequently (less than 6 hours between doses)

When to Seek Medical Attention

• Fever persists beyond 3 days
• Pain worsens or persists beyond 3 days
• Child develops rash, stomach pain, or vomiting after taking ibuprofen
• Symptoms worsen despite medication

Remember that ibuprofen is effective for both fever reduction and pain relief, making it an appropriate choice for managing common childhood illnesses when used at the correct dosage.