Why have you been prescribed neulasta

What is Neutropenia?

You are receiving chemotherapy to treat cancer.1 Chemotherapy works by destroying the fast-growing cancer cells in your body.2 At the same time, chemotherapy can damage healthy cells in your body, such as blood cells.1
Your blood is made up of many different types of components, which are formed in the bone marrow. One of the main components is the white blood cells, which are a vital part of your body’s immune system.3
Normally, the most common type of white blood cell is the neutrophil. This is a very important defense against most types of infection. Each neutrophil lives less than a day, so your bone marrow must constantly make new neutrophils to maintain protection against infection.3
Unfortunately, chemotherapy tends to stop your bone marrow making new neutrophils, which makes your immune system much weaker and less able to fight off any infection.4,5 Neutropenia is the term used when the number of neutrophils in your blood drops below the number that most people have in their blood i.e. low neutrophils. Low neutrophils are a common side effect of chemotherapy.5 Some people may even develop a fever that is often caused by an infection which is known as febrile neutropenia.2
People receiving chemotherapy may experience neutropenia, which is one of the most important risk factors for getting a serious infection.5

Chemotherapy works by killing fast-growing cancer cells.
Chemotherapy drugs can’t tell the difference between cancer cells and fast-growing healthy cells. A possible side effect of chemotherapy is a low count of neutrophils.6
Having a low neutrophil count is a condition known as neutropenia.
Neutropenia can raise your risk of developing certain types of infections. A low white blood cell count with fever, also known as febrile neutropenia, can be a sign of a serious infection.2 You should call your doctor or nurse right away if you get a fever higher than 38°C.7
Infection may be a risk throughout your chemotherapy treatment.
Your treatment plan may consist of multiple chemotherapy cycles. The risk of infection may be present in every one of them. Helping to reduce that risk should be an important consideration for you and your doctor/nurse.

Why have you been prescribed Neulasta®?

Neulasta® can be used to reduce the duration of neutropenia and the occurrence of febrile neutropenia after treatment with chemotherapy. By reducing the neutropenia, this can help in preventing infections.2
Before chemotherapy:
At natural levels, white blood cells such as neutrophils help protect your body against infection.
With chemotherapy:
Chemotherapy can reduce your neutrophil count. This may put you at risk for certain types of infection.
After chemotherapy:
Neulasta® can help stimulate the production of neutrophils, shortening the time and reducing the depth of a low white blood cell count after chemotherapy. This can help your body fight infection.2

How does Neulasta® work?

Neulasta® contains the active substance pegfilgrastim which is very similar to a protein found in your body (Granulocyte colony stimulating factor). It helps your bone marrow to make more neutrophils to replace those that have been lost through chemotherapy. By helping increase the number of neutrophils in your blood and bringing your neutrophil levels closer to normal, Neulasta® may help protect you against infection.2


  1. NHS. Chemotherapy. Available at: https://www.nhs.uk/conditions/chemotherapy/ [Last accessed: January 2021]
  2. Neulasta® (pegfilgrastim). Patient Information Leaflet. [Available at: https://www.medicines.ie/medicines/neulasta-pre-filled-syringe-34724/patient-info]
  3. American Society of Hematology. Blood basics. Available at: https://www.hematology.org/education/patients/blood-basics [Last accessed: January 2021]
  4. American Cancer Society. Chemotherapy Side Effects. Available at: https://www.cancer.org/treatment/treatments-and-side-effects/treatment-types/chemotherapy/chemotherapy-side-effects.html [Last accessed: January 2021]
  5. American Cancer Society. Low White Blood Cell Counts (Neutropenia). Available at: https://www.cancer.org/treatment/treatments-and-side-effects/physical-side-effects/low-blood-counts/neutropenia.html [Last accessed: January 2021]
  6. American Cancer Society. Causes of Infections. Available at: https://www.cancer.org/treatment/treatments-and-side-effects/physical-side-effects/low-blood-counts/infections/risk-for-infections.html [Last accessed: January 2021]
  7. NHS. Low white blood cell count. Available at: https://www.nhs.uk/conditions/low-white-blood-cell-count/ [Last accessed: January 2021]