Tylenol (acetaminophen) for babies: the rules

Tylenol / acetaminophen for babies and toddlers: by weight, how often, the under-2 and under-12-weeks rules, measuring

Reviewed October 19, 2026against 2 sources, listed below

When to call

Under 12 weeks: a fever may signal a serious infection and needs immediate medical attention. A temperature of 100.4°F (38.0°C) or higher at that age means being seen right away, not treating it at home.

The amount goes by the child's weight (by age only if the weight isn't known). The AAP publishes a weight table on its acetaminophen page.
Under 2 years: the AAP says acetaminophen should not be given without a doctor's guidance on the amount.
Under 12 years: no more often than every 4 hours, and no more than 5 doses in 24 hours.
Measure with the dosing syringe that comes with that medicine, never a kitchen spoon. Giving the wrong amount is one of the most common mistakes.
Avoid combination products (more than one ingredient) under age 6, so acetaminophen isn't given twice by accident.
Extra-strength and extended-release products, disintegrating tablets and suppositories aren't for young children unless a doctor directs it.
Fever after a vaccine can happen; talk to the child's doctor about it.

Log each dose as a medicine record: when two caregivers share the night, both see when the last dose was given, so it's never given twice.

Education from the sources listed, not medical advice. If you're worried about your child, call your pediatrician; in an emergency, call 911.