I get calls about parents concerned about their child’s fever, how high is too high, and what they can do for it. Here is a brief outline of elevated temperatures and fever.
Body temperature varies a degree or so over the course of a normal day. Fever develops when the immune system detects an infectious agent, like bacteria or viruses, and mounts a response to fight it off . In addition to infection, some vaccines can also cause fever. Bundling a child in too many clothes or blankets can increase the child’s temperature slightly, but does not cause fever.
- Rectal temperature above 100.4ºF
- Oral temperature above 99.5ºF
- Axillary (armpit) temperature above 99ºF
- Ear temperature above 100.4
Rectal temperatures are the most accurate. Temperatures measured in the armpit are the least accurate.
Next question is: Do you treat a fever? In most cases, a child with a fever can be monitored and treated at home. However, you should consult your doctor if:
- Your infant less than three months has a temperature of 100.4ºF or greater
- Your child older than three months has a temperature of 100.4ºF or greater for more than three days or who are fussy, clingy, refusing to drink fluids
- Your child is 3-36 months and has a temperature of 102ºF or greater
- Your child has a temperature of 104ºF or greater
- Your child has a febrile seizure.
- Your child has a fever and a chronic medical problem like heart disease, cancer, lupus, or sickle cell anemia
Treatment of fever is recommended if a child has an underlying medical problem, or if the child has had febrile seizures in the past.
Treatment is helpful, but not necessary, if the child is uncomfortable. Acetaminophen (eg, Tylenol®) or ibuprofen (Advil®, Motrin®) are the most effective at reducing fever by2 to 3ºF, and reducing the child’s discomfort. Do not give a child aspirin, as it can cause a rare condition known as Reye syndrome. Acetaminophen and ibuprofen are given on a weight-based scale. Call your doctor for this information.
Having a fever can increase a child’s risk of becoming dehydrated. To reduce this, encourage your child to drink fluids. If they refuse to drink, offer popsicles. As mentioned above, if you child doesn’t drink fluids, call your doctor.
Having a fever causes most children to feel tired and achy. Rest is the best treatment. Once they get to feeling better and their fever comes down, you can slowly reintroduce activity.