G-CSF (Granulocyte-colony stimulating factor)
What is G-CSF?
G-CSF (granulocyte-colony stimulating factor) is a type of protein called a growth factor.
G-CSF stimulates the bone marrow to make more blood cells, and increases the number of some types of white blood cells in the blood. It can be used with, or after, chemotherapy. It can also be used before and after a stem cell transplant.
G-CSF is made naturally in the body, but it can also be made as a drug. Treatments include:
- lenograstim (Granocyte®)
- filgrastim (Accofil®, Neupogen®, Nivestim®, and Zarzio®)
- lipegfilgastrim (Lonquex®)
- pegfilgrastim (Neulasta®, Pelgraz®, Pelmeg®, and Ziextenzo®).
It is best to read this information with our general information about the type of cancer you have and the treatment you are having.
Your doctor will talk to you about G-CSF and its possible side effects before you agree (consent) to have treatment.
When G-CSF is used
Chemotherapy
G-CSF is often given with chemotherapy. Chemotherapy can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is sometimes called neutropenia.
The number of white blood cells usually goes back up naturally between the cycles of chemotherapy. But some people need G-CSF to help increase their white blood cell count. This can reduce their risk of infection and mean that chemotherapy can be given on time and at the planned dose.
Collecting stem cells for treatment
A stem cell transplant is sometimes used to treat blood cancers.
Stem cells are blood cells at the earliest stage of their development.
You have a course of G-CSF injections for a few days. This stimulates your bone marrow to make more stem cells. These are then collected, stored and given when the transplant is needed.
How G-CSF is given
G-CSF is usually given as an injection under the skin (subcutaneously). It is usually given into your thigh or tummy area. You, or someone who looks after you, may be shown how to give the injections. Or they can be given by a nurse at home or at the GP surgery.
Some people have G-CSF as a drip into a vein, which takes about 30 minutes. You have this at the hospital or clinic.
During your treatment, you will have regular blood tests to check the number of white blood cells in your body. Your doctor or nurse will explain how often you need the injections.
Storing G-CSF
About side effects
We explain the most common side effects of this treatment here. We also include some less common side effects.
You may get some of the side effects we mention, but you are unlikely to get all of them. If you are also having treatment with other cancer drugs, you may have some side effects that we have not listed here. Always tell your doctor, nurse or pharmacist about any side effects you have.
Your doctor can give you drugs to help control some side effects. It is important to take them exactly as your nurse or pharmacist explains. This means they will be more likely to work for you. Your nurse will give you advice about managing your side effects. After your treatment is over, most side effects start to improve.
Serious and life-threatening side effects
Some cancer treatments can cause severe side effects. Rarely, these may be life-threatening. Your cancer doctor or nurse can explain the risk of these side effects to you.
Contact the hospital
Your nurse will give you telephone numbers for the hospital. If you feel unwell or need advice, you can call them at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.
More information
We cannot list every side effect for this treatment. There are some rare side effects that are not listed. You can visit the electronic Medicines Compendium (eMC) for more detailed information.
Side effects while treatment is being given
Some people may have side effects while they are being given this treatment or shortly after they have it.
Allergic reaction
Some people have an allergic reaction while having this treatment. Signs of a reaction can include:
- feeling hot or flushed
- a skin rash
- itching
- shivering
- feeling dizzy
- a headache
- feeling breathless.
If you feel unwell or have any of these signs, tell a doctor or nurse straight away. Do not take any more of this treatment until you have spoken to them.
Injection site
You may get pain, itching or redness where the injections are given. Having the injection in a different place each time can help with this.
Common side effects
Bone pain
This is caused by your bone marrow making blood cells. You might feel a dull ache in your pelvis (between your hips), your back, arms or legs. Tell your doctor or nurse if you have this. They may suggest medicines to help.
Headaches
This treatment may cause headaches. If you have headaches, tell your doctor. They may give you painkillers to help.
Bruising and bleeding
This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot.
If the number of platelets is low, you may bruise or bleed easily. You may have:
- nosebleeds
- bleeding gums
- heavy periods
- blood in your urine (pee) or stools (poo)
- tiny red or purple spots on the skin that may look like a rash.
Tell your doctor if you have any unexplained bruising or bleeding. You may need a drip to give you extra platelets. This is called a platelet transfusion.
Anaemia (low number of red blood cells)
This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may have symptoms such as:
- pale skin
- lack of energy
- feeling breathless
- feeling dizzy and light-headed.
Tell your doctor or nurse if you have these symptoms.
If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.
Fever and chills
You may get fever and chills as a side effect of G-CSF. If you notice this, tell your doctor or nurse. They may suggest medicines to help.
If you are having chemotherapy
G-CSF is often given with chemotherapy. Chemotherapy can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is sometimes called neutropenia.
An infection can be very serious when the number of white blood cells is low. It is important to get any infection treated as soon as possible. Contact the hospital straight away on the 24-hour contact number you have been given if:
- your temperature goes over 37.5°C (99.5°F)
- you suddenly feel unwell, even with a normal temperature
- you have symptoms of an infection
- your temperature goes below 36°C (96.8°F).
Symptoms of an infection include:
- feeling shivery and shaking
- a sore throat
- a cough
- breathlessness
- diarrhoea
- needing to pass urine (pee) a lot, or discomfort when you pass urine.
It is important to follow any specific advice your cancer treatment team gives you.
Feeling sick and loss of appetite
You may feel sick or not feel like eating while having G-CSF treatment. If this happens, talk to your doctor or nurse. They can give you anti-sickness drugs to help.
Constipation
This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:
- Drink at least 2 litres (3½ pints) of fluids each day.
- Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
- Do regular gentle exercise, like going for short walks.
If you have constipation, contact the hospital for advice. Your doctor can give you drugs called laxatives to help.
Diarrhoea
This treatment may cause diarrhoea. Diarrhoea means passing more stools (poo) than is usual for you, or having watery or loose stools. If you have a stoma, it will be more active than usual.
If you have diarrhoea:
- try to drink at least 2 litres (3½ pints) of fluids each day
- avoid alcohol, caffeine, milk products, high-fat foods and high-fibre foods
- contact the hospital for advice.
Tummy pain
Pain in left side of tummy or shoulder
The spleen is on the left side of the tummy (abdomen), just under the ribs. The spleen helps fight infection and also stores and breaks down blood cells.
G-CSF can cause your spleen to grow bigger. This is usually mild and goes away after you stop treatment. Symptoms of an enlarged spleen include discomfort on the left side of the tummy or shoulder, and feeling full quickly when eating. If you notice this, tell your doctor or nurse.
Skin changes
This treatment may affect your skin. It may cause a rash, which might be itchy. Your doctor or nurse can tell you what to expect. If your skin feels dry, try using an unperfumed moisturising cream every day.
Always tell your doctor or nurse about any changes to your skin. They can give you advice and may prescribe creams or medicines to help. Skin changes usually improve when treatment finishes.
Very rarely, this treatment may cause a more serious skin condition. You may have a skin rash which then blisters and your skin can peel. You may also feel unwell with flu-like symptoms such as a high temperature and joint pain. If this happens, contact the hospital straight away.
Less common side effects
Effects on the liver
This treatment may affect how your liver works. This is usually mild. You will have blood tests to check how well your liver is working.
Effects on the kidneys
This treatment can affect how your kidneys work. This is usually mild and goes back to normal after treatment finishes. You will have blood tests to check how well your kidneys are working. You may also have urine tests. Tell your doctor or nurse if you have blood in your urine (pee) or you are passing urine less than usual.
It is important to drink at least 2 litres (3½ pints) of non-alcoholic fluid each day to help protect your kidneys.
Build-up of fluid
This may lead to swelling of the ankles or feeling breathless. Talk to your doctor or nurse if you notice this. They may give you medicines to help.
Effects on the lungs
This treatment can cause changes to the lungs. Tell your doctor if you develop:
- a cough
- wheezing
- breathlessness.
You should also tell them if any existing breathing problems get worse. You may have tests to check your lungs.
Dizziness
Sleep problems
Other information
Blood clot risk
Cancer and some cancer treatments can increase the risk of a blood clot. Symptoms of a blood clot include:
- throbbing pain, redness or swelling in a leg or arm
- suddenly feeling breathless or coughing
- sharp chest pain, which may be worse when you cough or take a deep breath.
If you have any of these symptoms, contact the hospital straight away on the 24-hour contact number you have been given. If you cannot get through to your doctor, call the NHS urgent advice number on 111.
A blood clot is serious, but it can be treated with drugs that thin the blood (anticoagulants). Your doctor or nurse can give you more information.
You can help reduce the risk of developing a blood clot by:
- staying active during treatment
- drinking plenty of fluids, especially water.
You may be given anticoagulants to help prevent a clot.
Other medicines
Some medicines can affect how this treatment works or be harmful when you are having it. Always tell your cancer doctor about any drugs you are taking or planning to take, such as:
- medicines you have been prescribed
- medicines you buy in a shop or chemist
- vitamins, herbal drugs and complementary therapies.
Tell other doctors, pharmacists or dentists who prescribe or give you medicines that you are having this cancer treatment.
You can visit the electronic Medicines Compendium (eMC) for more detailed information about your treatment.
Sorbitol
Contraception
Your doctor will advise you not to get pregnant or make someone pregnant while having this treatment. The drugs may harm a developing baby. It is important to use contraception during your treatment and for a while after treatment finishes. Your doctor, nurse or pharmacist can tell you more about this.
Breastfeeding
You are advised not to breastfeed while having this treatment, or for some time after treatment finishes. This is because the drugs could be passed to the baby through breast milk.
Your doctor or nurse can give you more information.
Medical and dental treatment
If you need medical treatment for any reason other than cancer, always tell the doctors and nurses you are having cancer treatment. Give them the contact details for your cancer doctor so they can ask for advice.
If you think you need dental treatment, talk to your cancer doctor or nurse. Always tell your dentist you are having cancer treatment.
About our information
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References
Visit the electronic Medicines Compendium (eMC) to download a Patient Information Leaflet (PIL) for more detailed information. The leaflet lists all known side effects.
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Reviewers
This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert health professionals and people living with cancer.
Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.
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