Filgrastim

Filgrastim, sold under the brand name Neupogen among others, is a medication used to treat low neutrophil count. Low neutrophil counts may occur with HIV/AIDS, following chemotherapy or radiation poisoning, or be of an unknown cause. It may also be used to increase white blood cells for gathering during leukapheresis. It is given either by injection into a vein or under the skin. Filgrastim is a leukocyte growth factor. Common side effects include fever, cough, chest pain, joint pain, vomiting, and hair loss. Severe side effects include splenic rupture and allergic reactions. It is unclear if use in pregnancy is safe for the baby. Filgrastim is a recombinant form of the naturally occurring granulocyte colony-stimulating factor (G-CSF). It works by stimulating the body to increase neutrophil production. Filgrastim was approved for medical use in the United States in 1991. It is on the World Health Organization's List of Essential Medicines. Filgrastim biosimilar medications are available.