Taking Accurate Temperature Key to Treating Common Fever

By Dr. Jennifer Weglowski

Few things cause more anxiety than a child with a fever. It is not surprising, then, that fever is one of the most common reasons for contacting a doctor or seeking care in the emergency department. Despite enormous amounts of research to the contrary, the majority of parents still believe that fevers are dangerous and may lead to seizures, brain damage or even death. It is important to remember that fever is not an illness or disease in and of itself; it is actually a helpful response produced by the body to fight infection.

There is a great deal of confusion regarding what constitutes a normal body temperature and what is a fever. “Normal” body temperature is 98.6 degrees Fahrenheit although this can vary by plus or minus one degree depending on the child. Body temperature is always higher in the late afternoon and early evening and lower in the early morning. Doctors consider a temperature of 100.4 degrees or greater to be a fever.

The gold standard for checking the temperature is with a rectal thermometer, especially for children under 1 year old. Many parents are nervous or uncomfortable doing this but done properly does not cause pain to your child. Remember that it is not possible to measure your child’s temperature by simply feeling the forehead.

The only accurate way to take a temperature is with a thermometer. Digital thermometers are available at any pharmacy and are inexpensive and easy to use. Other ways to check the temperature are under the tongue, under the arm or in the ear; however these are less accurate and depend on how well your child cooperates and the quality of the device.

Most parents’ first instinct when their child has a fever is to treat it with a fever reducer such as acetaminophen or ibuprofen. Never give a child aspirin for a fever. This can lead to Reye Syndrome, a condition that affects the brain.

Many parents worry when the temperature does not return to “normal” or when the fever returns before it is time to give another dose. Remember that treating the fever does not cure the illness. The most important reason to treat a fever is to make your child more comfortable. You can also provide cool liquids for your child to drink, dress your child in light clothing, give your child a tepid sponge bath or place cool washcloths on the forehead, under the arms and between the legs and avoid bundling your child in blankets.

If you choose to give your child a fever reducer it is very important to give the right dose. Children’s dosing is based on their weight. Check with your doctor’s office to make sure you are giving the right dose of medicine. Your doctor must know the concentration of fever reducer you are giving to be sure you give the correct dose to avoid over- or under-dosing of the medication.

Most fevers in children are caused by viruses and will run their course in two to three days without any treatment. However, there are situations when you should contact your child’s doctor. These include:

• Your child is less than 3 months old.

• The fever is greater than 104 degrees Fahrenheit.

• Your child is lethargic or difficult to wake up.

• Your child refuses to eat or drink.

• Your child has a rash or difficulty breathing.

• There are any signs of dehydration including dry lips, sunken soft spot or decreased wet diapers.

• Your child has a seizure with the fever.

• Fever lasts more than 24 hours in a child less than 2 years old more than 72 hours in a child more than 2 years old.

• Your child looks sick or is not acting normally even after the fever comes down

The next time your child has a fever remember, don’t panic. It is a normal and beneficial response to illness and shows that your child’s immune system is working well.

Dr. Jennifer Weglowski is a member of the division of pediatric emergency medicine at Rady Children’s Hospital-San Diego and a clinical assistant professor in the department of pediatrics at UC San Diego. She can be reached at jweglowski@rchsd.org.