Your health
By Sally Robinson and Keith Bly

Most people feel 98.6 degrees Fahrenheit is normal body temperature. The truth is “normal” body temperature varies from person to person. Some people have a normal temperature that is a little higher than 98.6, and some have a lower temperature. 

Most people’s body temperature changes throughout the day. It usually is lower in the morning and higher in the evening. Most children’s temperature stays the same from day to day — until they get sick, from either a bacterial infection or a virus. 

Fever is not dangerous. It will not cause damage to the brain unless it rises above 107 degrees, and infections rarely cause fevers above 106.2 degrees. 

Temperatures above 107 usually are caused by heatstroke, head trauma, toxic ingestion or side effects from anesthesia. 

In general, our body temperature rises when our body is fighting infection. 

Fever is actually a good thing — it shows that our immune system is working to fight whatever illness we have. 

Fever occurs when the hypothalamus, which is located in the brain and acts as the body’s “thermostat,” responds to substances that are released in the blood by invading bacteria, viruses or toxins. The hypothalamus raises the body’s temperature and signals white blood cells to attack the invaders. 

Reducing fever may not make your child get better faster, but it will relieve some of the discomfort the fever may be causing him. In addition, if you reduce the fever, you may be able to tell if he is feeling miserable because of the fever or the infection. 

If you choose to reduce your child’s fever, you may give her acetaminophen or ibuprofen. Carefully follow the instructions on the package or talk to your pediatrician to determine the amount your child should take. Too much may be dangerous. Do not use aspirin to reduce a fever. Aspirin has been linked to Reye’s syndrome, which is a disease that causes severe liver dysfunction and brain swelling. 

Make sure your child drinks a lot of fluids. Loss of fluid due to sweating increases and can cause dehydration, which can make your child’s temperature rise. 

Don’t force your child to eat because people who have fever do not usually have much of an appetite. Once the infection has passed, your child will regain his appetite, as well as any weight that may have been lost. 

Make sure your child is wearing lightweight clothing. If your child feels cold, give her warm liquids. If your child complains of being too hot, dress her lightly. 

Fever is only one part of an illness, and for children younger than 8 years old, fever is not a reliable sign to determine how sick they are.

 Infants and toddlers can be very ill without having a high temperature, while children 3-8 years old can be running around as they normally do with a very high fever. 

The important thing is to see how your child is acting, rather than what the thermometer says. 

Sally Robinson is a clinical professor of pediatrics at the University of Texas Medical Branch at Galveston Children’s Hospital and Keith Bly is an assistant professor of pediatrics in the UTMB Children’s Emergency Room. This column is not intended to replace the advice of a physician.