Baby Tylenol Dosage Chart: Safe Doses by Weight

The safe dose of baby Tylenol (acetaminophen) is 10 to 15 mg per kilogram of your child's body weight, given every 4 hours as needed.

Always use your baby's weight, not their age, to figure out the right dose. You can give up to 5 doses in 24 hours, but never more. Do not give acetaminophen to babies under 12 weeks (3 months) old without your pediatrician's guidance. If your baby is under 3 months and has any fever at all, call your doctor right away, this needs medical evaluation, not home treatment.

Below you'll find a complete dosage chart by weight, plus everything you need to know about safely treating fever in babies with Tylenol.

What Is Baby Tylenol (Infant Acetaminophen)?

Baby Tylenol is a brand-name pain reliever and fever reducer made for infants and children. The active ingredient is acetaminophen (also called paracetamol outside the United States), one of the most widely studied and commonly used medications in pediatrics. It works by lowering fever and easing mild to moderate pain, and it is available over the counter without a prescription.

"Tylenol" is the most well-known brand name, but generic store-brand acetaminophen works just as well. The FDA requires all approved generics to contain the same active ingredient at the same concentration, so there is no difference in safety or effectiveness between brand-name and generic products.

Parents commonly use baby Tylenol for fevers, teething pain, post-vaccination discomfort, and ear infection pain. It comes as a flavored liquid that you measure with an oral syringe.

When Can You Give a Baby Tylenol?

Acetaminophen is generally safe for babies 12 weeks (3 months) and older, when used at the correct dose.

Most pediatricians follow these guidelines:

• Age minimum: 12 weeks (3 months). For any fever in a baby under 3 months, call your pediatrician immediately, do not give Tylenol at home.
• Post-vaccination exception: Some pediatricians may recommend acetaminophen for babies as young as 8 weeks after their vaccinations, but only if the baby develops a fever or seems uncomfortable afterward.
• Common uses: Fever reduction, teething pain, post-vaccination discomfort, and pain from ear infections.
• When NOT to give: Babies under 12 weeks, children with known liver disease, or anyone with an allergy to acetaminophen.

Important: Do not give acetaminophen before vaccines as a preventive measure. Research shows this may reduce the immune response to the vaccine. Only give it after, and only if your baby seems uncomfortable.

Baby Tylenol Dosage Chart by Weight

The right dose of baby Tylenol depends on your child's weight. Always use weight to determine the dose, use age only if you don't know your child's weight.

"Always dose acetaminophen by your child's weight, not their age, weight-based dosing is the medical standard for safety," says Dr. Melissa Tribuzio, MD, a board-certified pediatrician at Blueberry Pediatrics.

The standard concentration for all infant and children's liquid acetaminophen is 160 mg per 5 mL.

For babies under 12 weeks or under 6 lbs, consult your pediatrician before giving any acetaminophen.

How to Give Baby Tylenol Safely

Giving the right dose matters, but so does giving it the right way. Follow these tips every time.

• Always use the oral syringe that comes with the product. Studies consistently show oral syringes are significantly more accurate than dosing cups for measuring liquid medication. Never use a kitchen spoon, teaspoons and tablespoons are not precise enough and can lead to dosing errors.
• Give the liquid slowly, directing the syringe toward the inside of your baby's cheek (not straight to the back of the throat) to prevent choking.
• Wait at least 4 hours between doses. Never give more than 5 doses in 24 hours.
• Check all other medications for hidden acetaminophen. Many over-the-counter cold, flu, and cough medicines already contain acetaminophen. Giving Tylenol on top of these products could lead to an overdose.
• Store at room temperature (68 to 77 degrees F) and check the expiration date before each use.
• Keep all medications out of reach of children. A child-resistant cap is not a substitute for safe storage.

Infant Tylenol vs. Children's Tylenol: What's the Difference?

Infant Tylenol and Children's Tylenol are the exact same medication at the exact same concentration since 2011, 160 mg of acetaminophen per 5 mL.

The only real difference is the measuring device. Infant's Tylenol comes with an oral syringe (for smaller, more precise doses), while Children's Tylenol includes a dosing cup. That's why Infant's Tylenol often costs 2 to 3 times more, you're paying for the syringe, not a different formula.

Before 2011, infant drops were about 3 times more concentrated than children's liquid. This caused dangerous dosing errors when parents accidentally switched between products without adjusting the amount. The FDA standardized the concentration to prevent these mistakes.

If you have Children's Tylenol at home, you can use it for your infant as long as you measure with an oral syringe and dose by weight using the chart above. Check with your pediatrician if you have questions.

Can You Alternate Tylenol and Motrin (Ibuprofen)?

This is one of the most common questions parents ask, and the AAP position is clearer than many parents realize. The American Academy of Pediatrics recommends using a single medicine (either acetaminophen or ibuprofen) for a given fever, not routinely alternating between them.

Two reasons drive that recommendation:

• Combining or alternating regimens raises the chance of dosing errors, giving the wrong medicine, giving it too soon, or accidentally doubling up. Most alternating-regimen overdoses traced by Poison Control are caregiver-tracking errors, not dosing-formula errors.
• A 2024 AAP-published network meta-analysis (de la Cruz-Mena et al., Pediatrics 2024) found alternating regimens lowered temperature slightly more than a single medicine alone, but the accompanying AAP editorial noted that comfort and parent confidence, not the number on the thermometer, are the right outcomes, and the small temperature benefit does not outweigh the dosing-error risk at home.

Alternating is reserved for situations where your pediatrician has explicitly told you to do it and has given you a written schedule. If your pediatrician recommends alternating:

• Remember that ibuprofen (Motrin) is not safe for babies under 6 months. Only acetaminophen is an option below 6 months.
• Use a written log to track which medication you gave and when.
• Do not alternate for more than 24 hours without checking back with your doctor.

Common Baby Tylenol Questions

Here are the most common questions parents ask about giving their baby Tylenol.

How much infant Tylenol for a 2-month-old?

For a 2-month-old, the right answer almost always starts with a phone call to your pediatrician, not a syringe. AAP guidance says any fever of 100.4 degrees F or higher in a baby under 3 months needs same-day in-person evaluation, the medication is rarely the first step. If your pediatrician does direct you to dose, they will calculate the exact amount using your baby's current weight at 10 to 15 mg per kilogram, given no more often than every 4 hours.

How much infant Tylenol for a 4-month-old?

Most 4-month-olds weigh around 14 to 16 lb, which puts the standard Infant Tylenol dose at 80 mg, or 2.5 mL of the 160 mg/5 mL liquid. You can give one dose every 4 hours, up to 5 doses in 24 hours, while symptoms last. Always use the dosing syringe that came with the bottle, not a kitchen spoon, not the cup from another medicine. If your baby weighs more or less than this range, check the weight-based chart above and dose by weight, not age.

How much infant Tylenol for a 6-month-old?

A typical 6-month-old weighs about 16 to 17 lb (18 lb and up steps to 3.75 mL on the chart above). The standard dose at that weight is 80 mg of acetaminophen, which is 2.5 mL of Infant Tylenol 160 mg/5 mL. Give one dose every 4 hours as needed, with a hard cap of 5 doses in 24 hours. Six months is also the age when ibuprofen (Infant Motrin or Advil) becomes an option, but you should still pick one medicine per fever, not both. Use the included syringe, and dose by your baby's actual weight when you have it.

How much infant Tylenol for an 8-month-old?

Most 8-month-olds weigh in the 18–22 lb range. The standard dose at that size is 120 mg, or 3.75 mL of Infant Tylenol 160 mg/5 mL. Give one dose every 4 hours as needed, no more than 5 doses in any 24-hour stretch. If your baby is closer to 17 lb, drop to 80 mg (2.5 mL). If they are over 23 lb, step up to 160 mg (5 mL). Always measure with the included syringe, and check the strength on the bottle every single time before you draw up a dose.

How much infant Tylenol for a 1-year-old?

A 1-year-old typically weighs around 20 to 23 lb. The standard Infant Tylenol dose at that weight is 120 mg, or 3.75 mL of the 160 mg/5 mL liquid, given every 4 hours as needed, up to 5 doses per day. Once your child is over 24 lb, the next step up is 5 mL. You can use either Infant Tylenol or Children's Tylenol at this age, the concentration is identical (160 mg/5 mL). The only difference is the included measuring device (syringe vs. cup). Use whichever device came in the bottle.

How much Tylenol can I give my baby?

Dose by weight at 10 to 15 mg per kilogram of your baby's body weight, given every 4 hours as needed and no more than 5 doses in any 24-hour period. Use the dosage chart above to find the right amount based on your child's weight in pounds or kilograms — weight, not age, is what determines a safe dose. Two safety gates apply: do not give acetaminophen to a baby under 12 weeks (3 months) without your pediatrician's explicit OK, and any fever in a baby under 3 months needs a same-day call to a doctor, not a home dose.

Can I give my newborn Tylenol?

Do not give acetaminophen to babies under 12 weeks without your pediatrician's explicit guidance. Any fever (100.4 degrees F or higher, taken rectally) in a baby under 3 months requires immediate medical evaluation, not Tylenol at home.

How long does infant Tylenol take to work?

Most parents start to see Infant Tylenol's effect 30 to 60 minutes after the dose, with peak fever reduction around the 1- to 2-hour mark. Comfort, sleep, and feeding usually improve before the thermometer fully agrees with you. The full effect lasts about 4 to 6 hours, then wears off (this is the duration of the effect, not how often to give the next dose — the dosing interval stays every 4 hours, up to 5 doses in 24 hours). If your baby still feels miserable after a correct dose, do not double-dose, call your pediatrician. Babies with bacterial infections, dehydration, or other underlying issues sometimes don't respond well to fever reducers, and that itself is useful clinical information.

What if my baby spits out or vomits the Tylenol?

If your baby vomits within 20 minutes of taking the dose, you can give another full dose. If you're unsure how much your baby actually kept down, call your pediatrician or Poison Control (1-800-222-1222) before re-dosing. If more time has passed, wait and give the next dose at the regular 4-hour interval. Contact your pediatrician if vomiting continues.

What happens if I give too much infant Tylenol?

Acetaminophen overdose can cause liver damage, and the dangerous part is that a child may look completely normal for the first 24 hours after a toxic dose. Symptoms, nausea, abdominal pain, sleepiness, show up after liver injury has already started. If you think you gave the wrong dose, the wrong concentration, or more than 5 doses in 24 hours, call Poison Control at 1-800-222-1222 right away, even if your baby seems fine. Poison Control is free, confidential, 24/7. Do not wait for symptoms to appear before calling.

Is generic acetaminophen as effective as brand-name Tylenol?

Yes. Generic acetaminophen contains the identical active ingredient at the same concentration. The FDA requires bioequivalence for all approved generics, there is no clinical difference.

Can I give baby Tylenol for teething?

Yes, acetaminophen can relieve teething pain. Dose by weight using the chart above. The AAP also recommends firm rubber teething rings and gentle gum massage. Avoid teething gels containing benzocaine, the FDA warns against using these products in children under 2 due to the risk of a serious condition called methemoglobinemia (a rare but dangerous reaction that reduces the blood’s ability to carry oxygen).

Can I give Tylenol after vaccinations?

Tylenol is fine to treat an actual post-vaccine fever or fussiness using your baby's weight-based dose. What the AAP recommends against is giving Tylenol routinely before or right after every shot to try to prevent a fever, a 2009 study (Prymula, Lancet) found that prophylactic acetaminophen slightly lowered the antibody response to several routine vaccines. So: don't dose preventively, and don't dose every baby after every appointment. If your baby gets a real fever or is genuinely uncomfortable after vaccines, treating that fever with a correct dose is fine.

When to Call Your Pediatrician

Most fevers in children are harmless and resolve on their own. But some situations need a doctor's attention right away.

Call your pediatrician or seek medical care if:

• Your baby is under 3 months old and has any fever (100.4 degrees F or higher, rectal)
• Your child has a fever above 104 degrees F
• The fever lasts more than 3 days despite treatment
• You notice signs of an allergic reaction: rash, swelling, or difficulty breathing
• Your child accidentally took too much, call Poison Control at 1-800-222-1222 immediately
• Your child is unusually sleepy, won't stop crying, has a stiff neck, or shows other concerning symptoms

Remember what the AAP says: "The primary goal of treating a febrile child should be to improve the child's overall comfort rather than focus on normalization of body temperature." Fever is your child's immune system at work, treat the discomfort, not the number on the thermometer.

References

• Sullivan JE, Farrar HC; AAP Section on Clinical Pharmacology and Therapeutics, Committee on Drugs. "Fever and Antipyretic Use in Children." Pediatrics. 2011;127(3):e20103852.
• FDA Drug Safety Communication. "Addition of another concentration of liquid acetaminophen marketed for infants." December 22, 2011.
• AAP HealthyChildren.org. "Acetaminophen Dosing Tables for Fever and Pain in Children." Last updated 2026-01-30.
• AAP HealthyChildren.org. "Fever and Your Baby." Last updated 2025-09-23.
• Prymula R, Siegrist CA, Chlibek R, et al. "Effect of prophylactic paracetamol administration at time of vaccination on febrile reactions and antibody responses in children." The Lancet. 2009;374(9698):1339–1350.
• De la Cruz-Mena JE, Florez ID, et al. "Short-term Dual Therapy or Mono Therapy With Acetaminophen and Ibuprofen for Fever: A Network Meta-Analysis." Pediatrics. 2024;154(4):e2023065390.
• Antoon JW, et al. "Antipyretic Strategies: Is Fever Clearance Enough to Justify Dual Therapy?" (editorial) Pediatrics. 2024;154(4):e2024067408.
• AAP Journal Blog (2024). "When a Child Has a Fever, What Is Best? Acetaminophen, Ibuprofen, or Both?"
• Temple AR, et al. "Comparison of the Efficacy and Safety of 2 Acetaminophen Dosing Regimens in Febrile Infants and Children." PMC5341528.
• Pantell RH, et al. "Clinical Practice Guideline: Evaluation and Management of Well-Appearing Febrile Infants 8 to 60 Days Old." Pediatrics. 2021;148(2):e2021052228.
• Schaffer DH, Murray BP, Khazaeni B. "Acetaminophen Toxicity." StatPearls (NIH NBK441917). Last updated 2026-03-26.
• FDA. "Safely Soothing Teething Pain and Sensory Needs in Babies and Older Children." FDA Safety Communication, 2018.