Approved by the Cancer.Net Editorial Board, 02/2018

Neutropenia is when a person has a low level of neutrophils. Neutrophils are a type of white blood cell. All white blood cells help the body fight infection. Neutrophils fight infection by destroying harmful bacteria and fungi (yeast) that invade the body. Neutrophils are made in the bone marrow. Bone marrow is the spongy tissue found in larger bones such as the pelvis, vertebrae, and ribs.

Some level of neutropenia takes place in about half of people with cancer who are receiving chemotherapy. It is a common side effect in people with leukemia. If you have neutropenia, practice good personal hygiene to lower your risk of infection. This includes washing your hands regularly.

People who have neutropenia have a higher risk of getting serious infections. This is because they do not have enough neutrophils to kill organisms that cause infection. People with severe or long-lasting neutropenia are most likely to develop an infection.

Signs and symptoms of neutropenia

Neutropenia itself may not cause any symptoms. Patients usually find out they have neutropenia from a blood test or when they get an infection. Some people will feel more tired when they have neutropenia. Your doctor will schedule regular blood tests to look for neutropenia and other blood-related side effects of chemotherapy.

For patients with neutropenia, even a minor infection can quickly become serious. Talk with your health care team right away if you have any of these signs of infection:

  • A fever, which is a temperature of 100.5°F or higher

  • Chills or sweating

  • Sore throat, sores in the mouth, or a toothache

  • Abdominal pain

  • Pain near the anus

  • Pain or burning when urinating, or urinating often

  • Diarrhea or sores around the anus

  • A cough or shortness of breath

  • Any redness, swelling, or pain (especially around a cut, wound, or catheter)

  • Unusual vaginal discharge or itching

Causes of neutropenia

These factors related to cancer and cancer treatment can cause a low level of neutrophils:

  • Some types of chemotherapy

  • Cancers that affect the bone marrow directly, such as leukemia, lymphoma, and multiple myeloma

  • Cancer that has spread

  • Radiation therapy to several parts of the body or to bones in the pelvis, legs, chest, or abdomen

Some people with cancer are more likely to develop neutropenia, including:

  • People who are age 70 or older

  • People with a lowered immune system from other causes, such as HIV infection or organ transplant

Managing and treating neutropenia

An important part of cancer care is relieving the side effects of treatment. This is called palliative care or supportive care. Talk with your health care team about any symptoms you have, including any changes in symptoms.

The timing of the drop in neutrophil levels is based on the type or dose of chemotherapy. Neutrophil counts generally start to drop about a week after each round of chemotherapy begins. Neutrophil levels reach a low point about 7 to 14 days after treatment. This is called the nadir. At this point, you are most likely to develop an infection. Your neutrophil count then starts to rise again. This is because your bone marrow restarts normal production of neutrophils. But it may take 3 to 4 weeks to reach a normal level again.

When your neutrophil level returns to normal, you are ready for the next round of chemotherapy. However, your doctor may delay the next round or lower the dose of chemotherapy because:

  • You develop neutropenia

  • Your neutrophil level does not return to normal fast enough

Your doctor may recommend antibiotics during longer periods of neutropenia to try to prevent infections.

If chemotherapy causes neutropenia with a fever, your doctor may give you medications called white blood cell growth factors. These drugs help the body make more white blood cells. Read more about ASCO’s guideline on white blood cell growth factors.

Related Resources

Side Effects of Radiation Therapy

Side Effects of Chemotherapy

Side Effects

More Information

National Cancer Institute: Infection and Neutropenia

ASCO answers; NeutropeniaDownload ASCO's free Neutropenia fact sheet. This 1-page printable PDF introduction to neutropenia includes possible causes, symptoms, how it is diagnosed, treatment options, words to know, and questions to ask the healthcare team. Order printed copies of this fact sheet from the ASCO University Bookstore.