Indications
Filgrastim is used to raise the number of neutrophils (infection-fighting white blood cells). It is given to shorten the time neutrophils stay low after cancer chemotherapy and so lower the risk of serious infection, after a bone marrow transplant, and to move stem cells from the bone marrow into the blood so they can be collected for transplant. It is also used for severe long-term neutropenia (low neutrophils) and in some people with advanced HIV infection.
How It Works
Filgrastim is a laboratory-made copy of a natural protein called granulocyte colony-stimulating factor (G-CSF). It signals the bone marrow to make more neutrophils and release them into the blood.
Dosage and Administration
Filgrastim is given as prescribed by a specialist. It is injected under the skin or given as a drip into a vein. The dose depends on body weight and the reason for treatment. After chemotherapy it is usually started at least 24 hours after the chemotherapy dose and given daily until blood counts recover. It is given by a doctor or nurse, or at home by a patient or carer who has been trained. Regular blood tests are needed to check the counts.
Interactions
Do not give it in the 24 hours before or after chemotherapy, because rapidly dividing bone marrow cells are more sensitive to chemotherapy. Lithium may increase the release of neutrophils. Tell the doctor about all other medicines you take.
Contraindications
- Allergy to filgrastim, other G-CSF medicines (such as Pegfilgrastim), or to any ingredient.
Side Effects
Common: bone or muscle pain, back pain, headache, fever, tiredness, nausea, and redness or pain where it is injected. Bone pain can usually be eased with Paracetamol.
Get urgent medical help if you have pain in the upper left side of the tummy or at the tip of the left shoulder (this can mean an enlarged or ruptured spleen), cough, fever and difficulty breathing, swelling of the body, rapid weight gain or passing less urine, red or dark urine, or signs of allergy such as rash, swelling of the face or difficulty breathing.
Pregnancy and Lactation
There is limited information about use in pregnancy, so it is used only if the doctor decides the benefit outweighs the risk. It is not known whether it passes into breast milk; the doctor will advise whether to breastfeed during treatment.
Precautions and Warnings
People with sickle cell disease may have sickle cell crises and need close monitoring. Long-term use may affect bone density. Your blood counts and spleen size may be checked regularly. Tell the doctor if you have ever had lung problems or kidney disease.
Overdose
Too much filgrastim can raise the white cell count very high and may cause bone pain. The doctor will stop or adjust treatment and monitor blood counts.
Therapeutic Class
Haematopoietic growth factor (granulocyte colony-stimulating factor, G-CSF).
Storage
Store in a refrigerator at 2 to 8°C in the original carton to protect from light. Do not freeze and do not shake. If it is accidentally frozen or left out of the fridge longer than the leaflet allows, ask the pharmacist before use. Keep out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.