What is the recommended Tylenol (acetaminophen) dose for an 8.6 kg, 8-month-old infant?

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Acetaminophen (Tylenol) Dosing for an 8.6 kg, 8-month-old Infant

The recommended acetaminophen dose for an 8.6 kg, 8-month-old infant is 10-15 mg/kg/dose, which equals 86-129 mg per dose, given every 4-6 hours as needed, not to exceed 5 doses in 24 hours.

Dosing Calculation

For an 8.6 kg infant:

  • Minimum dose: 10 mg/kg × 8.6 kg = 86 mg
  • Maximum dose: 15 mg/kg × 8.6 kg = 129 mg

Administration Guidelines

Formulation Options

  • Infant liquid acetaminophen (160 mg/5 mL): 2.7-4.0 mL per dose
  • Use a calibrated dosing syringe or cup for accurate measurement

Dosing Schedule

  • Give every 4-6 hours as needed for fever or pain
  • Do not exceed 5 doses in 24 hours
  • Maximum daily dose: 75 mg/kg/day (645 mg for this infant)

Important Considerations

Safety Precautions

  • Always verify the concentration of acetaminophen product before administering
  • Never use adult formulations without proper measurement
  • Do not use for more than 3 consecutive days for fever or 5 days for pain without consulting a healthcare provider

When to Seek Medical Attention

  • If fever persists beyond 3 days
  • If pain persists beyond 5 days
  • If symptoms worsen despite treatment
  • If new symptoms develop

Common Errors to Avoid

  • Confusing infant and children's formulations (different concentrations)
  • Using household spoons instead of calibrated measuring devices
  • Administering doses too frequently
  • Giving acetaminophen simultaneously with combination products that also contain acetaminophen

Special Considerations

  • For persistent fever, alternating with ibuprofen may be considered for infants over 6 months, but only under healthcare provider guidance
  • Ensure adequate hydration during treatment

Remember that acetaminophen is generally considered the safest analgesic and antipyretic for infants when used at appropriate doses, but careful attention to dosing is essential to prevent potential hepatotoxicity from overdosing.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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