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Macmillan and Cancerbackup merged in 2008. Together we provide free, high quality information for people affected by cancer through our publications, website and phone service. Find out more|.
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This information is about G-CSF (granulocyte-colony stimulating factor). It describes G-CSF, how it is given and some of its possible side effects. It should ideally be read with our general information about your type of cancer|.
G-CSF is a special type of protein called a growth factor. It stimulates the bone marrow| to make white blood cells. The bone marrow is a spongy material inside the bones where all of our blood cells are made.
Growth factors are made naturally in the body. They can also be made outside the body and used as treatments.
There are three different types of G-CSF:
These treaments all work in similar ways.
G-CSF may be used during treatment with chemotherapy| to shorten the length of time that your white blood cell numbers are low.
One of the main side effects of chemotherapy is a reduction in the number of white blood cells in the body. White blood cells help us fight infections. So during the time your white blood cells are low, you're less able to fight infection|. And, if you develop an infection, it may make you more ill than it normally would.
White blood cell numbers are usually back to normal by the time the next dose of chemotherapy is due. But sometimes, if the levels of white blood cells are still low, the chemotherapy has to be postponed or the dose lowered.
G-CSF may be used to reduce the risk of infection and help make sure chemotherapy treatments are given on time and at the planned dose. It isn't needed with all types of chemotherapy, as white blood cell numbers usually recover on their own.
G-CSF may sometimes be used before high-dose chemotherapy to stimulate the bone marrow to make more stem cells. Stem cells are a special type of blood cell from which all other blood cells are made. The stem cells are collected from the blood and stored. They can then be given back to you after high-dose chemotherapy treatment and will make new blood cells to replace those you have lost. You might find it helpful to see our information about high-dose chemotherapy with stem cell support|.
G-CSF comes as a white powder to be dissolved in sterile water, or as a colourless fluid in a small glass bottle. It's also available in a pre-filled syringe.
G-CSF is usually given as an injection under the skin (subcutaneously). You, or the person caring for you, can be taught how to inject G-CSF so that you can continue the treatment at home. Alternatively, the injections may be given by a district nurse or GP practice nurse.
The levels of white blood cells in your body will be tested regularly while you're having growth factor injections.
G-CSF is usually started a few days after chemotherapy and given daily for up to 14 days. Pegylated filgrastim stays active in the body for longer, so it only needs to be given once with each cycle of chemotherapy.
After a G-CSF injection you'll have a much higher amount of it in your body than normal. You may have some side effects as a result, even though G-CSF is a natural substance. However, side effects aren't usually severe and get better after G-CSF treatment ends.
People react to drugs in different ways, so it isn't possible to predict who is going to have side effects or which they will have. We have outlined the most common side effects here but haven't included those that are rare and therefore unlikely to affect you.
If you notice any effects that aren't listed here, discuss them with your doctor or specialist nurse.
You may have some discomfort or a dull ache in the bones of your pelvis, back, arms or legs. Your doctor can prescribe painkillers if needed.
Your skin may become red and itchy around the area in which the injection is given.
Your doctor may prescribe painkillers, such as paracetamol to help reduce your temperature and prevent chills.
This may lead to swelling of the ankles or breathlessness|.
It's important to let your doctor know straight away if you feel unwell or have any severe side effects, even if they're not mentioned above.
Filgrastim and pegylated filgrastim should be stored in the fridge. Lenograstim can be stored at room temperature. Follow any storage instructions given by your pharmacist.
This section has been compiled using information from a number of reliable sources including:
British National Formulary. 60th edition. 2010. British Medical Association and Royal Pharmaceutical Society of Great Britain.
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