Fever in Babies: How to Respond Calmly and When to Call the Doctor

Few things rattle a new parent like a warm forehead at 2 a.m. A fever itself is usually the body's way of fighting infection — but in young babies, certain situations need prompt medical attention. Here is how to respond calmly and know when to call.

How to check your baby's temperature

For infants, a rectal temperature taken with a digital thermometer is considered the most accurate. (Ask your pediatrician or nurse to show you the technique at a checkup if you have never done it.) Forehead and ear thermometers are easier but less precise for young babies. A rectal temperature of 100.4°F (38°C) or higher is generally considered a fever in an infant.

Comfort measures while you assess

Keep your baby comfortable: dress them lightly, offer frequent feeds or fluids appropriate for their age, and keep the room comfortably cool. You do not need to bundle a feverish baby or try to 'sweat it out.' Watch how your baby is acting — alertness, feeding, wet diapers, and breathing tell you more than the number on the thermometer alone.

Do not give your baby any fever-reducing medication without guidance from your pediatrician — dosing depends on age and weight, and some products are not appropriate for young infants at all. When in doubt, call before you dose.

One common myth worth retiring: teething does not cause a true fever. It can make gums sore and babies fussy, but a rectal temperature of 100.4°F (38°C) or higher has another cause — treat it as a fever, not teething.

When to call your pediatrician or seek care

• Any fever of 100.4°F (38°C) or higher in a baby under 3 months — call right away, day or night.
• Fever with difficulty breathing, unusual sleepiness or difficulty waking, persistent vomiting, a rash, or signs of dehydration (few wet diapers, no tears when crying, sunken soft spot).
• Stiff neck, inconsolable crying that nothing soothes, or a bulging soft spot on the head — seek emergency care.
• Fever lasting more than a couple of days, or a fever that goes away and returns.
• Any seizure with fever — seek emergency care.
• Any time your parental instinct says something is wrong. Pediatricians would always rather hear from you.

Was this helpful? Browse more in Health & Safety, and remember — your pediatrician knows your baby best.