For most babies, acetaminophen (Tylenol) is the go-to fever reducer, and it can be given at any age with a pediatrician’s guidance. Ibuprofen (Motrin, Advil) becomes an option once your baby reaches 6 months old. Beyond medication, keeping your baby hydrated, lightly dressed, and comfortable matters just as much as bringing the number on the thermometer down.
Acetaminophen and Ibuprofen by Age
Acetaminophen has no formal age restriction and is the only fever-reducing medication recommended for babies under 6 months. It comes as a liquid syrup at a concentration of 160 mg per 5 mL. You can give it every 4 hours as needed, up to 5 doses in a 24-hour period. Always base the dose on your baby’s current weight, not their age, since weight is far more accurate.
Ibuprofen is not recommended for babies younger than 6 months. After that milestone, it can be given every 6 to 8 hours, up to 4 times in 24 hours. Ibuprofen tends to last a bit longer per dose than acetaminophen, which some parents find helpful overnight. Like acetaminophen, the correct dose is determined by weight. If your baby is between 12 and 17 pounds, for example, the typical ibuprofen dose is 50 mg (1.25 mL of infant drops). Between 18 and 23 pounds, it rises to 75 mg (1.875 mL).
Your pediatrician may suggest alternating the two medications if a fever is especially persistent. If you do this, keep a written log of what you gave and when to avoid accidentally doubling up.
What You Should Never Give
Aspirin is off-limits for children. It is linked to Reye’s syndrome, a rare but serious condition that causes sudden liver failure and brain swelling. Reye’s syndrome typically strikes after a viral illness, which is exactly when a parent might reach for a fever reducer. Since the 1980s, warnings on aspirin packaging have specifically flagged this risk for children with fevers. The rule applies to any product containing aspirin, including combination cold medicines, so always check the active ingredients label.
Measuring the Dose Safely
Nearly 40 percent of parents measure their child’s medication dose incorrectly, and using a kitchen spoon doubles the odds of a mistake. An NIH-funded study found that parents who measured doses in teaspoons and tablespoons were far more likely to grab a kitchen spoon rather than a calibrated tool. Thirty percent of them did so, compared to just 1 percent of parents who thought in milliliters.
The most accurate tool is an oral syringe marked in milliliters. Most liquid fever reducers come with one in the box. If yours didn’t, ask your pharmacist for one. Never substitute a kitchen teaspoon, even if you think it looks close to the right size. Even among parents using a proper dosing cup, those measuring in teaspoons still made more errors than those using milliliters.
Comfort Measures That Help
Medication isn’t always necessary for a mild fever. Sometimes keeping your baby comfortable is enough, especially if they’re still feeding, making eye contact, and acting reasonably like themselves. A few simple steps can make a noticeable difference.
Dress your baby in a single light layer. Even in winter, babies who are unwell or feverish don’t need extra blankets or clothing. Bundling a feverish baby can actually trap heat and drive the temperature higher. A room temperature between 60°F and 68°F (16 to 20°C) is comfortable and safe for sleep.
A lukewarm sponge bath can help bring a fever down without medication. Use water between 85°F and 90°F (29 to 32°C) and sponge gently for 20 to 30 minutes. If your baby starts shivering, stop immediately or warm the water slightly. Never add rubbing alcohol to the bath water. It can be absorbed through the skin and cause serious harm, including loss of consciousness.
Keeping Your Baby Hydrated
Fever increases fluid loss, making dehydration a real concern, especially in small babies. If you’re breastfeeding or formula feeding, offer feeds more frequently than usual. Babies older than 6 months can also have small sips of water between feeds.
Watch for signs that your baby isn’t getting enough fluid. In infants, fewer than six wet diapers in a day is an early warning sign of mild dehydration. A sunken soft spot on the top of the head is another signal. If your baby is only producing one or two wet diapers per day, that suggests more severe dehydration and needs prompt attention.
Temperature Thresholds That Need Attention
Not every fever requires a phone call, but age matters enormously in the first year of life. The younger the baby, the lower the threshold for concern.
- Under 3 months: A rectal temperature of 100.4°F (38°C) or higher needs immediate medical attention, regardless of how well your baby seems. At this age, a fever can signal a serious infection that’s hard to identify without testing.
- 3 to 6 months: Contact your pediatrician at 102°F (38.9°C) or higher.
- Over 6 months: A fever of 103°F (39.4°C) or higher warrants a call.
At any age, a fever paired with unusual sleepiness, refusal to feed, a rash, difficulty breathing, or persistent vomiting is worth a call to your pediatrician, even if the temperature falls below these cutoffs. The number on the thermometer is only part of the picture. How your baby looks and acts tells you just as much.