Neutropenia is a sign of acute and chronic conditions

Neutropenia is a condition in which the number of neutrophils in the blood is lower than normal. Neutrophils are the most common type of white blood cell. They help protect the body against infections.

A deficiency in the number of neutrophils can occur due to bone marrow disease, cancer, and hereditary conditions. Or, it can be an effect of medications or common cancer treatments. Neutropenia increases the risk and severity of infections.

This article will discuss the symptoms that may occur due to underlying conditions or complications of neutropenia, possible causes, tests, and treatment.

A man with neutropenia meets with a healthcare provider, both wearing masks for protection from infection.

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Symptoms of Conditions Associated With Neutropenia 

Neutrophils help fight bacterial and fungal infections, as well as healing from injuries and illnesses. Depending on the cause and severity of neutropenia, there can be an increased potential for infections.

The symptoms that may accompany neutropenia occur because of infections and impaired healing or from the underlying cause of neutropenia.

Common symptoms include:

  • Fatigue and feeling run down 
  • Fevers, especially high fevers above 103 degrees Fahrenheit 
  • Sweats or chills 
  • Myalgia (muscle aches)
  • Recurrent episodes of sore throat, mouth sores, non-healing wounds, diarrhea, or dysuria (pain with urination)
  • Abscesses (enclosed infections that are usually bacterial) 

Severe infections can cause shortness of breath or changes in consciousness and may require hospitalization.

If you have neutropenia, you may also experience symptoms associated with the cause of a low neutrophil count. For example, if your neutropenia is a side effect of chemotherapy medications, you may also have hair loss, nausea, vomiting, and bruises.

Types of Neutropenia 

Neutropenia can be hereditary, due to a genetic defect in neutrophil production, or it can be acquired.

Causes of Neutropenia 

Neutropenia is caused by any condition that affects the production or survival of healthy neutrophils. Sometimes this can be caused by a genetic defect, or it can be due to damage from disease or toxins.

Common causes include medications, radiation therapy, cancer, bone marrow disease, and infections. 

In general, when an infection causes neutropenia, it’s a temporary problem due to the body’s consumption of neutrophils. After a mild to moderate infection resolves, the neutrophils should return to a normal amount. 

Neutrophils are produced in the bone marrow. Bone marrow disorders, including aplastic anemia and myelodysplastic syndrome, can cause neutropenia. Some types of cancer can invade the bone marrow, preventing the normal production of neutrophils. Blood cancers may cause an excess of some blood cells and a deficiency of others.

Additionally, autoimmune diseases, which are generally associated with excess immune system activity, can cause a low number of neutrophils in the blood. 

What Medications Can Cause Neutropenia?

Many different medications can cause neutropenia, especially chemotherapeutic medications, which are used to treat cancer. However, other medications can also cause neutropenia. 

A sample of the medications that can cause neutropenia include:

  • Chemotherapy
  • Immunosuppressants
  • Clozaril (clozapine), an antipsychotic
  • Tegretol (carbamazepine), an anti-epilepsy drug
  • Vancocin (vancomycin), an antibiotic
  • Bactrim (sulfamethoxazole-trimethoprim), an antibiotic
  • Ticlid (ticlopidine), an anti-platelet agent used to prevent blood clots

Radiation therapy can also sometimes cause neutropenia. 


Chemotherapeutics usually cause neutropenia. But the extent of neutropenia isn’t the same for every chemotherapy medication or every person, and it can range from mild to severe.

How to Treat Neutropenia 

Neutropenia can often resolve within a few days or weeks if the cause is resolved. The complications of neutropenia usually have to be treated, and sometimes neutropenia can be treated too.

Treatment for neutropenia can include stopping and potentially replacing any medication causing it, if possible. Sometimes the medication can’t be stopped or replaced if it is necessary for treating cancer or another serious medical condition. 

Medications are sometimes prescribed to promote white blood cell production in the bone marrow. Examples include Neupogen (filgrastim), Granix (tbo-filgrastim), and Neulasta (pegfilgrastim).

Infections that occur due to neutropenia may need treatment with antibiotics, draining of an abscess, or surgery. In addition, symptomatic supportive treatment, such as oxygen supplementation for a severe lung infection, may be necessary.

Preventing Complications of Neutropenia

If you have neutropenia, it’s important that you try to avoid infections. This means taking precautions you might not otherwise need to take if your neutrophil count was normal. 

Precautions include:

  • Avoid getting cuts and wounds, extra care when using sharp objects.
  • Clean and cover wounds promptly.
  • Wash raw produce before eating and avoid food that could be contaminated with bacteria. 
  • Wash hands frequently, especially before eating, cooking, and after exposure to any potential germs .
  • Avoid crowds and wear a mask if you must be in a crowd. 
  • Avoid contact with anyone who has a contagious infection. 

These precautions are important for keeping your risk of infection as low as possible while you are neutropenic.  

Are There Tests that Can Diagnose the Cause of Neutropenia? 

Neutropenia is diagnosed with a complete blood count (CBC), which is a standard blood test. A CBC will identify the number and percent of different types of blood cells in the blood sample. 

The pattern of these changes helps differentiate the underlying cause of neutropenia. Often, neutropenia causes leukopenia (a low total white blood cell count) because neutrophils are usually the most prevalent type of white blood cell.

Sometimes neutropenia can occur with a normal or increased total white cell count if other white blood cells are abnormally high due to disease, cancer, or infection. 

Neutrophil count normally falls within a standard range.

Neutrophil counts can determine the severity of neutropenia
Neutrophil count (per microliter)
2,500 to 6,000 Normal
1,000 to 1,500 Mild neutropenia
500 to 1,000  Moderate neutropenia
less than 500 Severe neutropenia 

Because neutrophils can fluctuate, a healthcare provider may decide that serial testing may be needed if your neutrophil count is decreased.

If you have a known risk of neutropenia or are recovering from neutropenia, you might have regularly scheduled surveillance with CBC blood tests to see if your neutrophil count is low and if you need treatment.

Some tests can help determine the cause of neutropenia if it isn’t already known. Examples of tests that you might need if you have neutropenia, especially if there is not a known cause:

  • A peripheral blood smear, which is a microscopic evaluation of blood cells, can identify changes in the blood cell appearance.
  • A bone marrow biopsy can detect abnormal cells and cancer cells. In this test, a sample of bone marrow is aspirated and analyzed in the laboratory by a clinical pathologist (a specialist in diagnosing conditions by laboratory methods).
  • A lymph node biopsy can detect cancer cells. This is the surgical removal of a lymph node for analysis by a clinical pathologist.
  • A blood culture can detect a severe bacterial infection. In this test, blood is drawn into culture bottles and incubated to detect bacteria and identify any found.

Neutrophils normally compose approximately 40% of your white blood cells.

When to See a Healthcare Provider

You should see a healthcare provider if you develop signs of a severe infection. 

These include:

  • High fever 
  • Severe pain, swelling, warmth, or redness of part of the body 
  • A sore or wound that’s getting bigger or oozing pus
  • Difficulty breathing
  • A severe headache, dizziness, or confusion 

If you are severely immunocompromised (have a severely weakened immune system), you should talk to your healthcare provider about which signs of infection warrant urgent medical attention. 


Neutropenia, a low number of neutrophils, can be a medication side effect or can occur during and briefly after an infection. Blood cancers, cancer metastasis to the bone marrow, and bone marrow disease can also cause it. Depending on the cause and severity, neutropenia may increase the risk of infection.

Neutropenia is noted by a complete blood count test. If due to a medication or cancer treatment, it may be monitored until resolved. Medications may be given in some cases to stimulate neutrophil production.

A Word From Verywell 

Finding out that you have neutropenia can be stressful. In addition to the risks and health complications associated with neutropenia, you may also be dealing with a new diagnosis and other symptoms and treatment decisions related to your underlying condition.

It can seem like an overwhelming task, but make sure you get enough rest, eat healthy, stay active, and manage your stress—these things can help reduce your risk of infection and illness as you recover from neutropenia.

Frequently Asked Questions

  • What causes neutropenia?

    Many different factors can cause neutropenia, including medications, bone marrow disease, cancer, severe illness, and radiation therapy.

  • Does neutropenia always cause symptoms?

    Neutropenia doesn’t always cause symptoms, and it is more likely to cause noticeable problems if it is severe or prolonged.

  • Can you prevent symptoms of neutropenia?

    You should take extra precautions to avoid infections and injuries if you have neutropenia. This includes avoiding situations where you could be exposed to infections, even if these situations would be safe without neutropenia.

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Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Heidi Moawad, MD
Heidi Moawad is a neurologist and expert in the field of brain health and neurological disorders. Dr. Moawad regularly writes and edits health and career content for medical books and publications.