Cancer drugs A to Z list
Fludarabine is a type of chemotherapy drug. You pronounce it as flu-dar-ah-bin.
It is a treatment for some types of and . You usually have it in combination with other cancer drugs.
Fludarabine is one of a group of chemotherapy drugs known as . These stop cells making and repairing . Cancer cells need to make and repair DNA in order to grow and multiply.
Find out more about how chemotherapy works
You can have fludarabine as a drip into your bloodstream (intravenously). Or you take it as tablets.
You swallow the tablets whole with plenty of water. You do not chew or break them. You can take them on an empty stomach or with food.
You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:
central line
PICC line
portacath
You should take the right dose, not more or less.
Talk to your healthcare team before you stop taking a cancer drug, or if you miss a dose.
How often you have fludarabine depends on what lymphoma or leukaemia you have. Your doctor or nurse will tell you more about this.
Your doctor will adjust the dose depending on how well the treatment is working. They may lower the dose or stop the treatment if you are experiencing too many side effects.
You have blood tests before and during your treatment. They check your levels of and other substances in the blood. They also check how well your liver and kidneys are working.
Before treatment starts you may have a blood test to check for viruses such as hepatitis B, hepatitis C, and HIV. This is called a viral screen.
It’s important for your doctor to know if you have had any of these viruses. This is because this treatment can weaken your and can cause the virus to become active again (reactivation).
Side effects can vary from person to person. They also depend on what other treatments you're having.
Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:
you have severe side effects
your side effects aren’t getting any better
your side effects are getting worse
Early treatment can help manage side effects better.
We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.
Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.
These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:
Increased risk of getting an infection is due to a drop in . Symptoms include a change in temperature, aching muscles, cough, headaches, feeling cold and shivery, pain or a burning feeling when peeing or generally feeling unwell. You might have other symptoms depending on where the infection is.
Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection.
You might be breathless and look pale due to a drop in . This is called anaemia.
This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs. This is known as petechiae.
You might feel very tired and as though you lack energy.
Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.
Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also help.
It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treat it once it has started.
Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a , you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.
Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain . But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables.
Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.
Tell your healthcare team straight away if you get a high temperature. Ask them if you can take paracetamol to help lower your temperature.
You might develop a cough or breathing problems. This could be due to infection, such as pneumonia or inflammation of the lungs (pneumonitis).
These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:
numbness or tingling in fingers or toes (peripheral neuropathy)
a sore mouth
a skin rash
loss of appetite
fluid build up (oedema)
a second cancer such as and . Talk to your doctor if this of concern for you
changes to eyesight (vision), rarely this drug can cause blindness, inflammation or damage to the . Let your doctor or nurse know if you have eye pain, loss of vision, faded colour, flashing lights or blurred vision
chills
generally feeling unwell (malaise)
inflammation of the lining of the inside of your (mucosa) – symptoms depend on where the inflammation is, but they can include pain, bleeding, feeling or being sick, diarrhoea, blood or mucus in your poo and difficulty swallowing
These side effects happen in fewer than 1 in 100 people (less than 1%). You might have one or more of them. They include:
changes to how the liver works picked up on blood tests
a disorder where the body’s immune system attacks its own blood cells (an autoimmune disorder) such as autoimmune haemolytic anaemia, Evans syndrome and thrombocytopenic purpura. Talk to your doctor if this is of concern for you
bleeding from the stomach or bowel – symptoms can include blood in your poo or vomit, you might pass dark black tarry looking poo, you might be short of breath, tired and feel lightheaded
changes to the levels of chemicals in your blood due to the breakdown of tumour cells (tumour lysis syndrome). You have regular blood tests to check for this.
confusion
changes to how the works picked up on blood tests
seizure (fits)
feeling agitated
being unresponsive or unable to wake up (coma)
heart problems such as an irregular rhythm or the heart muscle not pumping properly. Symptoms of heart problems include shortness of breath, feeling light-headed, dizzy, swelling of your ankles or feet
a skin cancer
Stevens Johnson syndrome (SJS) or toxic epidermal necrolysis - a severe skin reaction that may start as tender patches. Depending on your skin tone this may look red, brown, grey, blue, purple or darker than your normal skin. This can lead to peeling or blistering of the skin. You might also feel feverish and your eyes may be more sensitive to light. This is serious and could be life threatening
There isn't enough information to work out how often these side effects might happen. You might have one or more of them. They include:
bleeding in the brain – symptoms include a severe sudden headache, confusion, weakness on one side of the body and vomiting
changes in the brain that are usually reversible, causing a sudden onset of symptoms including headaches, dizziness, confusion, fits (seizures) and changes to your vision
bleeding in the lungs – symptoms include coughing up blood, shortness of breath and feeling very tired
inflammation of the bladder – symptoms can include changes to how often you pee, it might be painful, you might pass blood or blood clots pain
We have more information about side effects and tips on how to cope with them.
Cancer drugs can interact with medicines, herbal products, and some food and drinks. We do not list these interactions on this page. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.
Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know if you have any other medical conditions or allergies.
After having this treatment you should only have blood or that are first treated with radiation (irradiated). The radiation lowers the risk of a reaction between your blood cells and the cells in the transfusion. No harm comes from the irradiated blood.
In your medical records there is a note saying you should only have irradiated blood. You have a card to carry with this information. This is in case you need treatment at another hospital.
This drug may harm a baby developing in the womb. It is important not to become pregnant or get someone pregnant while you are having treatment with this drug and for at least 6 months after treatment.
Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner become pregnant while having treatment.
You may not be able to become pregnant or get someone pregnant after treatment with this drug. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.
Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.
It is not known whether this drug comes through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment.
If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.
Do not have live vaccines while you’re having treatment and for up to 12 months afterwards. For some people, it may be longer than this. The length of time you need to avoid live vaccines depends on the treatment you’ve had.
Ask your doctor or pharmacist how long you should avoid live vaccinations.
In the UK, live vaccines include rubella, mumps, measles, chickenpox, BCG, and yellow fever. You can usually have non-live vaccines. But they might not give you as much protection as usual. These include the:
flu vaccine, as an injection
coronavirus (COVID-19) vaccine
Talk to your doctor or pharmacist about the best time to have a vaccine in relation to your cancer treatment.
You can be in contact with other people who have had live vaccines as injections. If someone has had a live vaccine by mouth or nasal spray there may be a small risk the vaccine virus can be passed onto you if your is weakened.
Your healthcare team will let you know if you need to take any precautions if you are in close contact with someone who has had a live vaccine.
For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.
You can report any side effect you have to the Medicines and Healthcare products Regulatory Agency (MHRA) as part of their Yellow Card Scheme.
Last reviewed: 05 Nov 2026
Next review due: 05 Nov 2029
Chemotherapy is a standard treatment for some types of cancer. It uses anti cancer drugs to destroy cancer cells.
Most chemotherapy side effects are temporary, but some people are affected months or years after treatment.
We have specific treatment information for each cancer type. Choose the cancer type you want to find out about the treatment from this A-Z list of treatments by cancer type.
Coping with cancer can be difficult. There is help and support available. Find out about the emotional, physical and practical effects of cancer and how to manage them.
