Side effects of B-ALL treatment

• Treatments for B-ALL do cause side effects, but everyone reacts to treatment differently.
• Side effects can range from mild to severe and can affect your mind as well as your body.
• Your hospital team can help you manage side effects.
• You can often stop many side effects from getting worse if you deal with them early,
• It’s very important to know about your risk of getting infections and take steps to avoid these.
• Most side effects of B-ALL treatment improve after treatment ends.

You may experience some short-term side effects from chemotherapy treatment. They could include:

• an achy flu-like feeling
• difficulty pooing (constipation)
• frequent watery poos (diarrhoea)
• bruising and bleeding
• extreme tiredness (fatigue)
• hair loss
• infections
• rashes
• a sore mouth or mouth ulcers (mucositis)
• feeling and being sick (nausea and vomiting)
• headache (this can also happen after a lumbar puncture)
• a blood clot – this could cause leg or chest pain, redness, or swelling
• damage to the nerves (peripheral neuropathy) which causes a burning feeling or pins and needles, or a loss of feeling, often in the hands and feet
• abnormal changes in your liver − this does not usually result in any symptoms, but sometimes causes the build-up of a substance called bilirubin in your body, which makes your skin look yellow (jaundice).

It’s important to remember that most side effects you get are only temporary.

If you do have side effects, tell your hospital team, as they may be able to help you manage them. For example, there are medicines you can take to help with feeling sick.

Find more information about coping with side effects.

Having B-ALL makes it more likely you’ll get infections, because the condition and the treatment affect your immune system.

If you do get an infection, it can become serious, because your body might not be able to fight it off. In some cases it can turn into sepsis, which is life-threatening.

It’s important to be aware of this. If you act fast when you have an infection, it can be treated before it gets worse.

There are simple things you can do to lower your risk of infection such as washing your hands often, staying away from anyone who is unwell and avoiding crowds and busy places.

There are two important things to do from the start:

• Find out who you can contact urgently (and out of hours) if you think you have an infection.
  
• Make sure you know the symptoms of infection and call your emergency contact number straight away if you have any of these symptoms.

Symptoms of an infection

These are common symptoms of an infection, but tell your hospital team straight away if you just don’t feel quite right.

• feeling hot or cold
• a cough producing green mucus
• sickness or frequent watery poos (diarrhoea)
• dizziness, headaches or a stiff neck
• skin that’s red, hot or swollen
• stinging when you wee or passing a small amount of wee
• generally not feeling well.

Asparaginase is a very important chemotherapy drug in the treatment of B-ALL. It kills the leukaemia cells by starving it of a key nutrient “asparagine”. Leukaemia cells need asparagine to grow and survive, so without it, they die off.

Asparaginase can sometimes cause side effects including:

• allergic reactions
• issues with the liver
• inflamed pancreas (pancreatitis)
• problems with blood clotting.

Sometimes, the side effects caused by asparaginase can be serious. Your hospital team will plan your treatment doses carefully, to try to reduce the risk of these side effects as much as possible. They’ll check your blood often and monitor you closely so they can catch any side effects early. They can tell you the sorts of signs and symptoms to look out for. Let them know if you have any concerns at any point.

Like any type of cancer treatment, blinatumomab can cause side effects. Your hospital team should give you information about the possible side effects and the symptoms to watch out for.

They’ll also tell you what to do and who to contact if you notice any side effects, or if you have any worries at all.

You’ll be monitored closely when you first start taking this treatment.

Below are just some of the side effects that can be caused by blinatumomab. Your hospital team can give you information on how likely these side effects may be for you individually.

Cytokine Release Syndrome (CRS)
Blinatumomab can cause something called Cytokine Release Syndrome (CRS). When your immune system attacks the leukaemia cells, it releases chemicals called cytokines. Sometimes, the immune system releases too many cytokines at once, and this can cause the body to become inflamed.

In most cases, CRS causes mild symptoms, like fever, feeling very tired and headaches. It’s rare, but some people having blinatumomab may have more severe symptoms that may require intensive care in hospital.

Neurotoxicity
Blinatumomab can affect how your brain and nerves work. This is called neurotoxicity. Symptoms can include headaches, shaking (tremors), confusion, problems with your thinking, memory or movement, or finding it difficult to talk or write. In some cases, it can cause serious neurological problems, like weakness on one side of the body, weakness in the legs, or seizures.

If you develop neurotoxicity, your hospital team may stop your blinatumomab infusion. This usually quickly reverses symptoms. Most people recover fully without it causing long-term problems.

Steroids can cause side effects such as:

• increased appetite
• mood changes and feeling irritable
• weight gain
• muscle weakness (especially in the legs).

If you have any of these side effects it’s worth discussing this with your hospital team, as they may be able to help.

Active treatment for B-ALL can cause side effects and make people feel unwell. The aim of supportive care is to support your body through some of the side effects and problems caused by B-ALL and active treatment, to help you feel as well as possible.

Everyone on active treatment will be offered supportive care, whether they're having intensive or less intensive treatment.

Supportive care can include:

Complementary therapies are treatments that are used at the same time as active treatment. Complementary therapy doesn’t replace medical treatment. The aim of complementary therapy is to help you feel better by easing symptoms and side effects of blood cancer and its treatment, and boosting your energy levels. Some people find that complementary therapies also helps them sleep better and feel less stressed.

Complementary therapies include things like:

• massage
• reiki
• reflexology
• aromatherapy
• meditation
• mindful breathing
• acupuncture.

If you are interested in trying complementary therapies, always talk to your hospital team or GP first, as some types of therapy may not be right for you.

Your hospital team may be able to refer you to complementary therapies within your hospital or tell you of a local cancer support centre that is trained to offer this service. You might have to join a waiting list before you can access these services.

Most side effects that people get from treatment for B-ALL are short-term. They usually improve after your treatment has finished. Some, however, will last longer, and some may even be permanent (not go away).

Side effects which start during treatment, or shortly afterwards, and last months or years after treatment has finished, are called "long-term side effects". Side effects that develop months or sometimes years after blood cancer treatment has finished, are called "late effects".

Your risk of getting long-term side effects or late effects can depend on factors like:

• the type and intensity of treatment you received
• whether you had a stem cell transplant as part of your treatment.
• your age at the time of treatment – those treated at a younger age have more time to develop certain late effects throughout their life
• other health conditions you may have

These days, treatment for B-ALL is risk-adapted, meaning that treatment is more tailored to individual need. This means that the long-term and late effects of B-ALL treatment in adults are becoming less common, because people are not being given more treatment or higher doses of treatment than they need. However, some people will still experience long-term side effects and late effects, including

• extreme tiredness (fatigue)
• problems with the thyroid (a gland in your neck)
• changes to how the heart or lungs work
• weakening of the bones
• hormonal changes
• changes to the mind and memory (sometimes called “brain fog”)
• changes to fertility.

Your hospital team can tell you if there are certain long-term side effects or late effects that you may be more likely to experience. They will also talk to you about how they will monitor you for these after you finish your treatment.

This information has been accredited with the PIF TICK, the UK's only quality mark for trusted health information.

Last full review June 2026. Next full review due June 2029. We may make factual updates between reviews.

Thank you to Consultant Haematologists Professor Adele Fielding and Dr Clare Rowntree for checking the clinical accuracy of our adult B-cell acute lymphoblastic leukaemia (B-ALL) information.

Thank you also to Karis, Ricky, Binu, Harry, Keri and Jesús for sharing their experiences and for helping with the creation of this information.