Fever
A fever is a body temperature that is higher than normal. But, a normal temperature in one person might be different from a normal temperature in another person. This is why it's important to find out what your cancer care team thinks might be a fever for you. They will tell you what temperature you should consider higher than normal.
Fever is usually caused by an infection. Other causes of fever may include inflammation, medication reactions, or tumor growth. Sometimes, the cause might not be known or easy to find. In an infection, the fever is a result of your body trying to fight invading germs. Fever is an important natural defense against germs.
People getting cancer treatments have a higher risk for infections because cancer treatment can cause neutropenia, a condition in which you have fewer white blood cells than normal to help fight infections.
To know if you have a fever, you will need to take your temperature. To take your temperature, you will need a thermometer. Ask your cancer care team what kind of thermometer is best. You can buy an easy-to-use oral thermometer (one made to take your temperature by mouth) at any drugstore so you can check to see if you have a fever. If you have any of the following symptoms, it is important that you take your temperature:
- Increased skin temperature
- Feeling warm
- Feeling tired
- Headache
- Feeling cold
- Shaking chills
- Body aches
- Skin rashes
- Any new area of redness or swelling
- Pus or yellowish discharge from an injury or other location
- New cough or shortness of breath
- New belly pain
- Burning or pain when urinating
- Sore throat
- You are confused, forgetful, aren’t making sense, or can’t tell where you are.
Neutropenic fever
You may have heard your cancer care team talk about neutropenic fever. In patients with neutropenia, fever may often be the first and sometimes only sign of infection. If this happens, your cancer care team will assess you and likely start treatment for infection right away. Treatment of a patient with neutropenic fever usually means starting the patient on antibiotics before they take tests that will confirm an infection.
What the patient can do
- If you start feeling warm or cold, check your temperature by mouth every 2 to 3 hours. If you can’t hold a thermometer in your mouth , hold it under your arm, in your armpit. Call your cancer care team if you have a fever (your cancer care team will tell you the temperature they consider a fever). Someone on the team will let you know if you need to be seen right away or if you need to wait and keep monitoring your temperature.
- Keep a record of temperature readings.
- Drink a lot of liquids (such as water, fruit juices, ice pops, and soups).
- Get enough rest.
- Use a cold compress on your forehead if you feel hot.
- Do not take medication to reduce your fever without asking your doctor. Remember that medication to reduce a fever will only help reduce your temperature - it will not take away an infection.
What caregivers can do
- Watch for shaking chills, and check the patient’s temperature after the shaking stops.
- Check the patient’s temperature by placing the thermometer in the mouth or in their armpit. (Do not take the temperature rectally unless you’ve been told it’s OK). If the patient has a fever, call the cancer care team for instructions on whether to be seen right away or to continue monitoring the fever.
- Offer extra fluids and snacks.
- Help the patient take their medicines on schedule.
- Encourage visitors who have a fever, diarrhea, a cough, or the flu to visit the patient only by phone until they are well again.
- Written by
- References
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Freifeld AG, Kaul DR. Infection in the patient With cancer. In Niederhuber JE, Armitage JO, Kastan MB, Doroshow JH, Tepper JE, eds. Abeloff’s Clinical Oncology. 6th ed. Philadelphia, PA: Elsevier; 2020:544-562
National Comprehensive Cancer Network (NCCN). Prevention and treatment of cancer-related infections. 2018. Version 1.2019. Accessed at https://www.nccn.org/professionals/physician_gls/PDF/infections.pdf on August 27, 2019.
Palmore TN, Parta M, Cuellar-Rodriguez J, Gea-Banacloche JC. Infections in the cancer patient. In DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 11th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2019:2037-2068.
Last Revised: February 1, 2020
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