What are the recommended doses of Tylenol (acetaminophen) and ibuprofen for a 3.5 month old infant who is teething?

Acetaminophen and Ibuprofen Dosing for a 3.5-Month-Old Teething Infant

For a 3.5-month-old infant who is teething, acetaminophen (Tylenol) can be given at a dose of 3 mg/kg every 6 hours, but ibuprofen is not recommended as it is only approved for infants 6 months and older.

Acetaminophen (Tylenol) Dosing

Acetaminophen is the preferred medication for pain management in infants under 6 months of age:

• Recommended dose: 3 mg/kg per dose
• Frequency: Every 6 hours as needed
• Administration: Use the liquid formulation with a calibrated medication syringe for accurate dosing
• Maximum daily dose: Should not exceed 15 mg/kg/day in this age group

For example, if your infant weighs 6 kg (about 13 lbs):

• Each dose would be 18 mg (3 mg/kg × 6 kg)
• Use the infant formulation (usually 160 mg/5 mL)

Ibuprofen (Motrin/Advil) Considerations

Ibuprofen is not recommended for this infant because:

• It is only approved for infants 6 months and older 1
• Safety data for infants under 6 months is limited
• The risk of adverse effects outweighs potential benefits in this age group

Non-Pharmacological Management of Teething

In addition to acetaminophen, consider these non-pharmacological approaches:

• Provide clean, chilled (not frozen) teething rings for the infant to chew on 2
• Gently massage the infant's gums with a clean finger 3
• Ensure adequate hydration during teething episodes
• Use a clean, damp washcloth for the infant to chew on

Important Safety Considerations

• Avoid topical lidocaine-based teething gels, as they have been associated with serious adverse effects including seizures and respiratory arrest in infants 4
• Do not use homeopathic teething remedies without medical guidance
• Monitor for signs of dehydration if the infant has feeding difficulties due to teething discomfort
• Consult your pediatrician if fever exceeds 38°C (100.4°F) or if symptoms persist beyond 2-3 days, as these may indicate conditions other than teething

When to Seek Medical Attention

Contact your pediatrician immediately if:

• Fever exceeds 38°C (100.4°F)
• Symptoms worsen or persist beyond 2-3 days
• The infant shows signs of ear infection, respiratory illness, or other conditions
• The infant refuses to feed for multiple feedings
• You observe unusual irritability or lethargy

Remember that while teething can cause discomfort, high fevers and significant illness are not typically attributed to teething alone and warrant medical evaluation.