Neutropenic Fever During Cancer Treatment

This page is for people in cancer treatment, and their caregivers, who want to understand neutropenic fever and when to get help.

Neutropenic fever means a fever at a time when infection-fighting white blood cells may be low. Cancer teams treat this carefully. Infection risk can change quickly during chemotherapy, transplant, and some other treatments.

The absolute neutrophil count (ANC) is the number of infection-fighting neutrophils in your blood. MedlinePlus says an adult with fewer than 1,000 neutrophils per microliter generally has neutropenia. Fewer than 500 is severe neutropenia. The count is a lab result you will not have at home. So the fever is your trigger. CDC and MedlinePlus use 100.4°F (38°C). NCI describes a fever as 100.5°F (38°C) or higher. Do not wait for the higher number, or an hour, to call. One reading of 100.4°F (38°C) or higher during chemotherapy means calling right away (CDC). Your own team may give you a lower temperature to call about. Use their number.

This page is a planning aid. It cannot diagnose the cause of a symptom. It cannot replace the instructions from your oncology team.

CDC says a fever may be the only sign of an infection. So the care team may need more information, including the treatment schedule, blood counts, temperature pattern, medicines, and other symptoms.

CDC says white blood cell counts usually reach their lowest point 7 to 12 days after each chemotherapy dose, which is when infection risk is highest. Ask your team for your own dates. If your team already gave you an urgent call plan, use that plan first.

• Temperature readings and times, if your team told you to measure them.
• The date of your last chemotherapy, transplant, or immune-weakening treatment.
• Your most recent white blood cell or neutrophil result, if you have it.
• Chills, shaking, cough, pain, urinary symptoms, rash, dizziness, or confusion.
• Antibiotics, steroids, fever reducers, or other medicines already taken.

• What is the most likely cause in my situation, and what else needs to be ruled out?
• Which symptoms or changes mean I should call right away?
• What information should I track before I call or come in?
• Could this affect treatment timing, dose, or supportive medicines?
• Who should I contact after hours, and what should I say first?

Your team will decide which tests and treatment you need. The plan may also change, or you may be watched more closely. The important point is not to self-diagnose the cause of the fever.

Ask what result or symptom pattern would change the plan. Ask what can be watched, and what should not wait until the next routine visit.

• Do not assume a symptom is "just treatment" without checking the plan your team gave you.
• Do not assume the same symptom means the same thing for every cancer treatment.
• Do not start a new over-the-counter medicine, supplement, or major diet change without asking the care team while symptoms are active.

Neutropenic fever is a medical emergency. CDC says an infection during chemotherapy can be life-threatening. Nothing on this page should be watched overnight.

• Call 911 or go to an emergency department if you have a fever together with confusion, drowsiness you cannot shake off, dizziness or feeling faint, fast breathing, trouble breathing, or shaking chills. CDC lists confusion, shortness of breath, fever or shivering, and a high heart rate or weak pulse among the signs of sepsis, a life-threatening emergency. Do not drive yourself.
• Go to an emergency department if you cannot reach your care team quickly and you have a temperature of 100.4°F (38°C) or higher during or after chemotherapy, a transplant, or another immune-weakening treatment. Say at the desk that you are having chemotherapy and may be neutropenic. MedlinePlus advises telling staff right away rather than waiting in the reception area.
• Call your care team immediately, at any hour, if your temperature is 100.4°F (38°C) or higher. Do not take paracetamol, acetaminophen, aspirin, ibuprofen, or another fever reducer first unless your team told you to. NCI says these can lower a fever but hide a more serious problem.
• Call your care team right away, at any hour, if you have no fever but have chills or sweats, a new or changed cough, a sore throat or new mouth sore, shortness of breath, a stuffy nose, or a stiff neck. Call right away, too, for burning or pain when you pass urine, diarrhea, vomiting, a new rash, belly or rectal pain, new pain, or pain, redness, swelling or discharge around a central line or port (CDC). Low neutrophils can blunt the usual signs of infection, so a small change matters more than usual. MedlinePlus also says to call right away for signs of infection, and calls an infection during cancer treatment an emergency.
• Call your care team immediately, at any hour, if your team gave you a lower temperature threshold and you have reached it, even though it is below 100.4°F (38°C). Their number is the one to use.

Helpful next pages include Fever During Chemo: What to Know, Low White Blood Cells During Chemotherapy, Neutropenia During Chemotherapy, Side Effects of Cancer Treatment.

• CDC — Watch Out for Fever (Preventing Infections in Cancer Patients)
• CDC — Signs and Symptoms of Infection
• CDC — About Sepsis
• MedlinePlus — Low white blood cell count and cancer
• MedlinePlus — Cancer treatment: preventing infection
• National Cancer Institute — Infection and Neutropenia