Filgrastim is a white blood cell growth factor known as granulocyte colony-stimulating factor (G-CSF). Growth factors are substances that are produced naturally in the body but can also be made using certain technology for it to be used as a medicine.
This medicine stimulates the growth of neutrophils, a type of white blood cell that helps your body to fight infections. It is used to increase neutrophil counts and help reduce the risk of infection in various conditions, such as when:
- undergoing chemotherapy for certain cancer
- receiving certain medical procedures e.g. bone marrow transplant
- having certain types of severe long-term neutropenia (abnormally low white blood cells called neutrophils)
- having advanced HIV infection
Filgrastim may be used to treat other conditions as decided by your doctor.
Filgrastim is to be injected subcutaneously (into the fatty layer under the skin, usually in the thigh or abdomen area). If you or your caregiver had been given the proper training on the preparation and injection techniques of this medicine, you or your caregiver may do the administration.
It may also be given intravenously (into the vein) as an infusion. When given intravenously, your doctor or nurse will administer the injection for you.
The dose and schedule of administration of this medicine will be decided by your doctor. Your doctor will advise you on the course of treatment depending on your condition and response to the medication.
If you are given the intravenous injection, ensure that you keep all appointments with your doctor so that you do not miss any doses. Your doctor also needs to regularly monitor your response to Filgrastim.
If you miss an appointment or miss an injection, alert your doctor or nurse. A replacement appointment or injection should be given as soon as possible.
If you or a caregiver had been trained to administer the subcutaneous injection and missed a dose, inject the missed dose as soon as you remember and return to your normal dosing schedule.
DO NOT double a dose under any circumstances.
Inform your doctor or pharmacist immediately if you forgot to administer your dose.
Do not use Filgrastim if you ever had an allergic reaction (e.g. rashes, breathlessness, swollen eyes) to this medicine or similar medicines such as pegfilgrastim.
Alert your doctor if you have severe congenital neutropenia (a rare inherited blood disorder characterised by severely low neutrophil counts) then developed any signs of leukaemia (cancer of the blood) as Filgrastim may not be suitable for you.
Inform your doctor if you have the following conditions:
- cancer of the bone marrow or blood
- sickle-cell disease (inherited condition in which the haemoglobin in red blood cells are damaged and unable to carry oxygen throughout your body)
- recent history of pneumonia (infection and inflammation of the lungs)
- osteoporosis (thinning and weakening of the bone)
Let your doctor know if you are pregnant or breastfeeding.
Do not switch between different brands unless advised by your doctor.
If you are going to undergo certain medical procedures or tests (e.g. bone imaging), inform your doctor that you are being treated with Filgrastim.
Why is it important to keep my appointments with the doctor?
Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly.
- Routine tests (e.g. complete blood count, bone marrow tests, spleen size) may be done while you are being treated with this medicine. Your doctor will advise you about how often you will need to have these tests.
- Monitoring for signs and symptoms of allergic reactions may also be needed.
Filgrastim may cause dizziness. If affected, do not drive or take part in any activity in which you need to be alert.
Other side effects include any of the following: headache, cough, nosebleeds, diarrhoea, nausea, vomiting, constipation, tiredness or weakness, decreased appetite, muscle pain or spasm, bone pain, difficulty sleeping, and hair loss.
Some side effects may need immediate medical help. Alert your doctor quickly if you experience any of the following:
- rashes, breathlessness, swelling of the face, eyes, mouth or throat
- pain in the upper left side of the stomach, left shoulder pain
- difficulty breathing, fever, persistent cough
- dark-coloured urine, blood in the urine, swelling of the ankles or feet, decreased urination
- unusual bleeding or bruising
Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Inform your doctor and pharmacist if you are taking or using any of these medicines:
- medicines for cancer e.g. bleomycin, cyclophosphamide, fluorouracil, topotecan
- lithium (medicine for mood disorders)
This list does not include all medicines that may interact with Filgrastim.
Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
Store in the refrigerator, between 2-8°C.
Store away from the reach of children. Protect from light or direct sunlight.
If you notice that the injection has changed colour or has become cloudy, do not use it. Throw it away and use a new injection.
Medicines must not be used past the expiry date.