Neulasta (pegfilgrastim) – Treatment for Low Neutrophil Count

Neulasta (pegfilgrastim) is a drug given to patients who have neutropenia (low neutrophil count). An injection of Neulasta stimulates white blood cell production with a synthetic version of a granulocyte colony-stimulating factor (G-CSF). It is a clear liquid that is usually given as a shot in which the needle is inserted just under the skin.

Chemotherapy for breast cancer affects all the rapidly dividing cells in your body, including bone marrow cells, which produce white and red blood cells, and platelets. If your CBC shows that your neutrophil count is low, you may be neutropenic. Injections of Neulasta can boost production of your neutrophils, a special type of white blood cell that helps your body fight infections.

Usually, your body produces a protein that stimulates the production of neutrophils. But during chemo for breast cancer, your body may not make enough of this protein. Your CBC may reveal that your neutrophil blood counts are low and that you are neutropenic. The proper dose of this drug will boost production of your neutrophils.

You will get an injection of Neulasta about 24 hours after your chemotherapy infusion. It may not be given sooner because it may be less effective. Unlike Neupogen, which must be given repeatedly until your neutrophil counts rise, Neulasta is given just once per a 2- or 3-week chemotherapy cycle. You can have this injection in your upper arm, abdomen, thigh, or buttocks.

Not everyone has side effects from Neulasta, but here are the most commonly known:

• bone pain
• fever

If you do have these side effects, you can take Tylenol (acetaminophen) or Advil (ibuprofen) to help reduce pain and fever. Soaking in a hot bath can also help with bone pain from Neulasta.

• unusual fatigue and lethargy
• chest pain
• heart palpitations
• mouth sores

Urgent symptoms include:

• allergic reaction (hives; problems breathing; swelling of face, lips, tongue or throat; rash spreading over your body)
• abdominal pain
• shoulder pain

Neulasta is a very safe drug used for many types of neutrapenia. There are usually no ill effects from this drug. Any side effects you experience will taper off and cease when you stop receiving Neulasta shots. There have been cases of spleen rupture resulting in death, though this is exceedingly rare.

Do not take this drug if:

• you are pregnant or breastfeeding
• you are allergic to Neulasta
• you are allergic to products made using the bacteria E. coli

Before your first injection of Neulasta, your doctor will order regular CBCs to get the levels of your platelets and red and white blood cells, with special attention to your neutrophils. As treatment progresses, you will have more blood tests to check the effectiveness of Neulasta.

If you are nursing or pregnant, discuss this with your doctor before taking Neulasta. There have not been enough studies done to determine the effect of this drug on breast milk or the human fetus.