Many cancer chemotherapy medications decrease bone marrow production of red blood cells and white blood cells, an effect called myelosuppression. A low level of white blood cells can leave you vulnerable to serious bacterial infections that may be life threatening. This adverse side effect is countered with medications called myeloid growth factors, which boost the white blood cell count.
Filgrastim
Filgrastim (brand name Neupogen) is a myeloid growth factor, which stimulates bone marrow production of granulocytes--the most abundant of the white blood cell types. This drug is also known as granulocyte colony-stimulating factor or G-CSF. Filgrastim is typically administered as a once daily subcutaneous (under the skin) injection; it can also be given intravenously. It is available in pre-filled syringes ready for injection. The dose and duration of treatment depend on the specific chemotherapy regimen you are on and how your granulocyte count responds to the drug. Common side effects of filgrastim include bone and muscle pain, headache, cough, nausea and vomiting.
Pegfilgrastim
Pegfilgrastim (brand name Neulasta) is a long-acting version of filgrastim. The primary drug, filgrastim, is chemically linked to a chemical called polyethylene glycol, or PEG. The attached PEG keeps the drug in the circulation for a longer period compared to filgrastim, which is rapidly cleared from the body. Like filgrastim, pegfilgrastim boosts bone marrow production and release of granulocytes. The drug is administrered as a subcutaneous injection, typically once per cycle of chemotherapy. Your doctor will determine the timing and dose of the drug. Common side effects of pegfilgrastim include bone and joint pain, muscle pain and constipation.
Sargramostim
Sargramostim (brand name Leukine) is a myeloid growth factor, which stimulates bone marrow production of granulocytes and monocytes (also known as macrophages). Sargramostim is also known as granulocyte-macrophage colony-stimulating factor or GM-CSF. This drug has been approved by the U.S. Food and Drug Administration for use in people undergoing chemotherapy for acute myelogenous leukemia and bone marrow transplants. It may be used in other clinical circumstances as well. Sargramostim is administered intravenously or as a subcutaneous injection. Your doctor will determine the dose and duration of treatment depending on your diagnosis and response to the drug. Common side effects of sargramostim include bone and muscle pain, fever and diarrhea.
