Definition of baby fever
Kiss or touch your baby’s forehead. If you think he feels hotter than normal, you’re probably right. A higher-than-normal body temperature is called a fever.
A fever is usually a sign that the body is waging a war against infection. Taking your baby’s temperature can confirm your suspicions and help you and your child’s doctor figure out the best way to get your baby back on the road to health.
Most doctors – and the American Academy of Pediatrics (AAP) — agree that a normal body temperature for a healthy baby is between 97 degrees F (36.1 degrees C) and 100.3 degrees F (37.9 degrees C). If your baby’s rectal temperature is 100.4 degrees F (38 degrees C) or higher, he has a fever.
Symptoms of a serious fever
A temperature reading isn’t the only indication of whether a fever is serious.
Age is a factor: Fever is more serious in babies under 3 months.
Behavior is another factor: A high fever that doesn’t stop your baby from playing and feeding normally may not be cause for alarm.
Keep in mind that everyone’s temperature rises in the late afternoon and early evening and falls between midnight and early morning. This natural cycle of our internal thermostat explains why doctors get most of their phone calls about fever in the late afternoon and early evening.
When to call the doctor
You’re the best judge of whether your baby is really ill – so do call if you’re worried, no matter what his temperature is. Ask your baby’s doctor for more specific advice, but generally:
- If your baby is under 3 months old and has a temperature of 100.4 degrees F (38 degrees C) or higher, call the doctor immediately. A baby this young needs to be checked for serious infection or disease.
- If your baby is 3 months old or older, the most important thing is how he looks and acts. If he appears well and is taking fluids, there’s no need to call the doctor unless the fever persists for more than 24 hours or is very high. Ask your doctor for additional guidance: For example, the doctor may suggest calling right away if your baby’s fever reaches 104 degrees, regardless of symptoms.
- The AAP suggests calling the doctor if a baby is between 3 months and 6 months old and has a fever of 101 degrees F (38.3 degrees C) or higher, or is older than 6 months and has a temperature of 103 degrees F (39.4 degrees C) or higher – and has symptoms such as a loss of appetite, cough, signs of an earache, unusual fussiness or sleepiness, or vomiting or diarrhea.
Also call the doctor if:
- Your baby is noticeably pale or flushed, or has fewer wet diapers.
- You notice an unexplained rash, which could indicate a more serious problem when coupled with a fever. Small, purple-red spots that don’t turn white or paler when you press on them, or large purple blotches, can signal a very serious bacterial infection.
- Your baby has difficulty breathing (working harder to breathe or breathing faster than usual) even after you clear his nose with a bulb syringe. This could indicate pneumonia or bronchiolitis.
- Your baby seems sick and his temperature is lower than normal (less than 97 degrees F/36 degrees C). Very young babies sometimes become cold rather than hot when they’re ill.
If your baby is under 3 months old, your doctor will probably ask you to bring him in to be examined. She may tell you not to give your baby any fever-reducing medicine until after she has taken an accurate temperature reading.
If your baby is 3 months or older, is reasonably alert and taking fluids, and has no other symptoms that suggest a serious illness, the doctor may advise simply waiting 24 hours before bringing him in. Because fever is often the first symptom of an illness, a doctor may not find anything significant if your baby is examined too early.
Depending on how uncomfortable your baby is, the doctor may suggest giving him children’s acetaminophen (or ibuprofen, if your baby is at least 6 months old) to bring down the fever.
Whatever your baby’s age, if he has symptoms that suggest a serious illness or infection, the doctor will instruct you to bring him in to be evaluated, either to the office (if you call during working hours) or to an emergency room.
Treatment of baby fever
Since fever is part of the body’s defense against bacteria and viruses, some researchers suggest that an elevated temperature may help the body fight infections more effectively. (Bacteria and viruses prefer an environment that’s around 98.6 degrees F/ 37 degrees C.) A fever also tells the body to make more white blood cells and antibodies to fight the infection.
On the other hand, if your baby’s temperature is too high, he’ll be too uncomfortable to eat, drink, or sleep, making it harder for him to get better.
If your little one’s fever isn’t affecting his behavior, you don’t need to give him anything to lower it. Offer plenty of breast milk or formula to prevent dehydration, and don’t overdress your child or bundle him up when he’s sleeping.
If your baby’s body temperature is higher than normal because of extra clothes or a scorching day, help him cool down by taking off a few of his layers and letting him rest or play quietly in a cool spot.
Medicine for fever
If fever is making your baby uncomfortable and your doctor says it’s okay, you can use infant acetaminophen or ibuprofen to bring down your baby’s temperature. (Ibuprofen isn’t recommended for babies under 6 months or for those who are dehydrated or have persistent vomiting.)
Be very careful when administering medicine to your baby. His weight will determine the right dose. Always use the measuring device that comes with the medicine to give your baby exactly the right amount.
Don’t give fever-reducing medicine more often than is recommended. The directions will probably say that you can give acetaminophen every four hours (up to a maximum of five times per day) and ibuprofen every six hours (up to a maximum of four times per day). Never give your baby aspirin. Aspirin can make a child more susceptible to Reye’s syndrome, a rare but potentially fatal disorder.
A final word of caution: Most doctors don’t recommend over-the-counter cough and cold preparations for babies, but if your baby is taking a prescription remedy, talk with the doctor before giving your baby any other medicine, such as ibuprofen or acetaminophen. Cough and cold remedies may already contain these products, so you risk giving your baby too much medicine.
Find out if you need to check with the doctor before giving pain medicine to your baby.
Sponge baths for fever
You can try to reduce your baby’s fever by sponging him down with tepid (lukewarm, not cold) water or giving him a lukewarm bath.
Never try to reduce a fever by sponging down your baby with rubbing alcohol. Rubbing alcohol can be absorbed into your baby’s bloodstream through the skin. It can also cool him too quickly, which can actually raise his temperature.
Fevers sometimes cause febrile seizures in babies and young children. They’re most common in children between the ages of 6 months and 5 years.
A child having this type of seizure may roll his eyes, drool, or vomit. His limbs may become stiff and his body may twitch or jerk. In most cases, the seizures are harmless, but that doesn’t make it any less terrifying if your baby’s having one.
Read more about febrile seizures and how to handle them.
Fever that keeps coming back
Fever-reducing medicine brings down body temperature temporarily. It doesn’t affect the bug that’s causing the infection, so your baby may run a fever until his body is clear of the infection. This can take at least two or three days.
Some infections, such as influenza (the flu), can last five to seven days. And if your baby is being treated with antibiotics to fight a bacterial infection, it may take 48 hours for his temperature to fall.
Fever with no other symptoms
When a baby has a fever that isn’t accompanied by a runny nose, a cough, vomiting, or diarrhea, figuring out what’s wrong can be difficult.
There are many viral infections that can cause a fever without any other symptoms. Some, such as roseola, cause three days of very high fever followed by a light pink rash on the trunk.
More serious infections, such as meningitis, urinary tract infections, or bacteremia (bacteria in the bloodstream), may also trigger a high fever without any other specific symptoms. If your baby has a persistent (longer than 24 hours) fever of 102.2 degrees F (39 degrees C) or higher, call the doctor, whether or not he has other symptoms.