During your baby’s first two years you may spend more time treating and worrying about fever than any other concern. Consider a fever like the “Check Engine” light in your car. It alerts you that something concerning is going on in your child’s body and needs to be checked carefully.
Fever is a symptom of an underlying illness. It is a normal and healthy response of the body to an infection. A baby’s normal body temperature varies from around 97–99 degrees Fahrenheit and can normally be up to a degree higher in late afternoon. Here’s how we rate fever:
Low-grade: between 99 and 100.9 degrees
Moderate: between 101 and 102.9 degrees
High: higher than 103 degrees
Taking Baby’s Temperature
The first thing to do is to make sure you are measuring your baby’s temperature correctly, so pay attention to any instructions that come with your thermometer. Ask your healthcare provider which new “high tech” thermometer they recommend.
Should a low-grade fever be treated?
Usually not. Low-grade fevers are helpful in fighting off infection. You should only treat a fever when it is making your baby uncomfortable. If the fever doesn’t seem to be bothering your baby, there is no need to treat the fever.
Lowering Baby’s Fever
How your baby acts is more important than how high their temperature is. The most important rule is to “treat the child, not the fever.” Here are some fever-lowering tips:
Don’t overclothe baby. Over-bundling keeps in heat. In the summer, it is best to let baby run around and sleep in diapers only, or at most in lightweight, loose-fitting cotton clothing. This allows excess heat to escape from your baby’s body into the cooler air.
Keep the environment cool. Open a window in baby’s room. Cool air helps remove the heat that is radiating from your baby’s hot body. Fresh air is good for baby.
Give baby a cool dip. Place baby in a lukewarm bath. Adjust the water temperature so that it is just warm enough to be comfortable for baby. Hot babies usually protest cold water, and it can make them shiver, increasing the body’s temperature. It usually requires at least 20 minutes to bring baby’s temperature down two degrees.
Give extra fluids. Fever makes the body thirsty. Sweating and rapid breathing cause the body to lose fluids that need replacing. Breastfeeding is a good source of fluids and comfort.
Acetaminophen and ibuprofen are the fever-lowering medications of choice for infants and children. They can begin to lower your baby’s temperature within a half hour. Drops are usually easier for infants under a year, syrups for children 1 to 3 years, and chewable tablets for children over 3 years. Check with your healthcare provider about what medication and dosage to use.
Do not give fever-reducing medications to an infant 3 months or younger until after you have sought medical care. Your doctor must first evaluate how your infant is doing without the aid of medications.
WHEN NOT TO WORRY
- The fever is overall low-grade.
- Your baby feels ill and subdued when the fever spikes, yet perks up when the temperature comes down.
- Overall your baby is feeling well, sleeping well, playing on and off and active fairly normal.
LOG THE FEVER’S COURSE
When seeking medical evaluation for your child’s fever, keep a journal. Your doctor will need this helpful information:
- Did it start suddenly or gradually?
- Is the pattern up and down or consistently high?
- How long has baby had the fever?
- Does baby display other symptoms: cold, rash, intestinal issues, and so on?
- Is baby getting worse or better?
You should only treat a fever when it is making your baby uncomfortable. If the fever doesn’t seem to be bothering your baby, no need to treat the fever.
WHEN TO SEEK MEDICAL ATTENTION
The younger the baby, the more the worry. Any rectal temperature of 100.4 degrees or higher in an infant less than 3 months of age that persists more than eight hours should be reported to your doctor.
- Your baby appears to be in pain.
- Your baby has spikes of high fevers for more than 48 hours.
- Your baby is gradually worsening.
When in doubt, check it out. If your intuition is telling you there may be something serious going on, listen to yourself. It’s better to be safe than sorry. There’s nothing wrong with taking your child to the doctor and being told it’s a relatively harmless virus, especially if it gives you peace of mind. Like most concerns of infancy and early childhood, as your child’s immune system matures, this stage of frequent fevers will pass.
Bill Sears, M.D., is a father of eight and the author of 42 books on family health, including The Healthiest Kid in the Neighborhood. A practicing pediatrician for over 40 years, he is an Associate Clinical Professor of Pediatrics at the University of California, Irvine, School of Medicine. Dr. Sears is a fellow of the American Academy of Pediatrics (AAP) and a fellow of the Royal College of Pediatricians (RCP).
Fevers by the numbers
While “normal” body temperature is 98.6° F (37° C), a child’s temperature can vary slightly from that standard. A normal temperature range is between 97.5° F (36.4° C) and 99.5° F (37.5° C). It also fluctuates throughout the day, with highest temperature between late afternoon and early evening, and lowest between midnight and the early morning.
Except for children under 3 months, deciding whether to visit the doctor should consider your child’s behavior as much as the thermometer’s reading. Even high fevers are common and not necessarily indicative of dangerous illness. For the most part, there is no direct correlation between the degree of fever and the severity of an illness.
What constitutes a fever also depends on how a child’s temperature is taken. Typically, rectal thermometers offer the most accurate temperature readings for infants and young toddlers; oral thermometers provide greatest accuracy for older children. (Most children can manage an oral thermometer at 4 years of age.)
|Thermometer type||Fever threshold|
|Axillary (armpit)||99.0° F (37.2° C)|
|Ear*||100.4° F (38° C)|
|Oral||100.0° F (37.8° C)|
|Pacifier*||100.0° F (37.8° C)|
|Rectal||100.4° F (38° C)|
|Temporal artery*||100.4° F (38° C)|
*Ear, pacifier, and temporal artery thermometers are not as reliable as digital multiuse thermometers, in part because ambient temperatures affect their readings.