Side effects
Side effects are unwanted things that happen to you as a result of medical treatment. The side effects that you might have and how severe they are depend on a number of factors including:
the type of treatment you have
the combination of treatments you have
the amount (dose) of the drug or radiotherapy
the way you have a drug – as tablets or capsules, or by injection
your general health
your age
Many people are worried about the possible side effects of treatment. All treatments cause some side effects. But side effects vary from one person to another.
Treatments for leukaemia are continuing to improve. This means that more people are surviving with fewer side effects. There are medicines to help control most side effects that happen during or straight after treatment. Many of these effects stop when the treatment ends.
Side effects might be short or long term.
Short term side effects happen when you have the treatment or very soon after you finish. The side effects depend on which treatments you have.
Some common side effects of treatment include:
an increased risk of infection
breathlessness and looking pale
tiredness and weakness
bruising, bleeding gums or nosebleeds
feeling or being sick
difficulty eating
sore mouth and ulcers
taste changes
diarrhoea
constipation
hair thinning and loss
changes in how your heart words
less interest in sex
periods stopping
breakdown of tumour cells (tumour lysis syndrome)
ALL and its treatment can cause a drop in the number of white blood cells. White blood cells are very important and helping fight infection.
Neutrophils are a particular type of white blood cell that have an important role in fighting infection. Having a very low number of neutrophils is called neutropenia.
If you have neutropenia you are at risk of developing a serious condition called neutropenic sepsis. This can be life threatening. This is more likely to happen with chemotherapy and other treatments that lower the immune system.
After your treatment it may take some time to build up your body’s ability to fight infection. After a it usually takes between 6 months to a year for your immune system to recover.
The symptoms of infection include:
a sore throat
a high temperature
pain when passing urine
a cough or breathlessness
flu-like symptoms, such as aching muscles, tiredness, headaches, and feeling shivery
People shouldn't visit you in hospital or at home if they have any kind of infection. Your healthcare team will let you know if you need to avoid very crowded areas where the risk of picking up an infection is greater. Once the level of your white blood cells recovers, you may be able to socialise more.
After a stem cell transplant, you need to have your vaccinations again. Each hospital has their own guidelines about when to vaccinate following a transplant.
You usually have antibiotic, antifungal and antiviral medicine while having chemotherapy to prevent you from getting an infection. You may also have a medication called a growth factor if your white blood cell count is low. You usually have this as an injection just under the skin.
Treatment can cause a low number of red blood cells. Red blood cells contain haemoglobin which carries oxygen around the body. If the level of haemoglobin in your blood is low this is known as anaemia. You may can feel very tired. You may also become breathless because the amount of oxygen carried around your body is lower. Some cancer drugs can make you anaemic.
You can have a if your red blood cells are very low. After a transfusion you will feel more energetic, less tired and less breathless. Some people worry they may get an infection from a blood transfusion. All blood is now very carefully screened before it is used. The chances of getting an infection from a transfusion are tiny.
ALL and its treatment can cause a low number of platelets. Platelets help to clot the blood to prevent bleeding.
If the number of platelets in your blood is low, you may:
bruise easily
bleed more than usual, even from small cuts or grazes
have nosebleeds
have a rash of small purple or red dots
The rash is called purpura and is caused by bleeding within the skin.
If your platelet count is very low, you need to have a platelet transfusion in hospital. You have a drip of a clear fluid containing platelets into your vein. The new platelets start to work right away.
If you still have periods, you will have medicine to stop them. This is to help lower the risk of bleeding problems.
Feeling or being sick is usually well controlled with anti sickness medicines. 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 treating it once it has started.
Tips:
Avoid eating or preparing food when you feel sick.
Avoid hot fried foods, fatty foods or foods with a strong smell.
Eat several small meals and snacks each day.
Relaxation techniques help control sickness for some people.
Ginger can help – try it as crystallised stem ginger, ginger tea or ginger ale.
Sip high calorie drinks if you can’t eat.
Try fizzy drinks.
Find out more about sickness and cancer drugs
Cancer treatments can affect your appetite and cause problems with eating, drinking and digestion.
There may be times when you won’t have much of an appetite. Try small meals throughout the day and eat whenever you feel like it. Your dietitian will give you high calorie drinks if you can't eat much. Some people having more intensive treatment might have liquid nutrition through a tube into their tummy or through your central line.
Some treatment for ALL can change the cells in the lining of your mouth, making it inflamed and sore (mucositis). You may develop mouth ulcers. This can happen several days after you start treatment. It usually gradually clears up 3 to 4 weeks after your treatment ends.
Tell your doctor or nurse straightaway if your mouth is painful and if you have mouth ulcers. They will talk you through how to look after your mouth and keep it clean. Some people need strong painkillers to help control mouth pain so that they can eat and drink.
Sometimes mouth ulcers can get infected. Your doctor or nurse can give you treatment for this. If you are having drugs that are known to cause mouth ulcers, your nurse may give you mouth washes to help prevent infection. You have to use these regularly to get the most protection.
Tips:
Keep your mouth and teeth clean with a soft toothbrush.
Talk to your doctor or nurse about flossing.
Avoid mouth washes that contain alcohol, your doctor may give you a mouthwash that can help with pain and inflammation.
Drink plenty of fluids.
Eat soft, moist foods and avoid food and drinks that irritate your mouth including alcohol.
Avoid acidic foods such as oranges, lemons and grapefruits.
Use lip balm and chew gum to keep your lips and mouth moist.
Find out more about your mouth and cancer drugs
Some cancer drugs can make food taste strange or may give you a metallic taste in your mouth. Food may taste:
salty
bitter
metallic
Your taste usually gradually goes back to normal when your treatment is over, but it may take a few weeks.
Find out about ways to help cope with taste changes
Diarrhoea is when you need to poo more often than you usually do in one day. And your poo is more loose and watery than usual. You can become dehydrated if you have severe diarrhoea. So it’s important to drink plenty of fluid. Ask your healthcare team whether you need to make any changes to your diet.
You may also want to apply soothing cream around your back passage (anus). The skin in this area can get very sore and even broken if you have severe diarrhoea.
Constipation is easier to sort out if you treat it early. Drink plenty of fluids and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your doctor or nurse if you are constipated for more than 3 days. They can prescribe a laxative.
Find out more about constipation
Some cancer drugs may cause:
mild thinning of your hair
partial hair loss or loss of patches of hair
complete hair loss (alopecia)
Generally, chemotherapy is the type of cancer drug treatment most likely to cause hair loss or hair thinning. But it is also a possible side effect with some targeted and immunotherapy drugs. Whether you will have this depends on:
the type of drug or combination of drugs you have
the amount (dose)
your individual sensitivity to the drug
your drug treatment in the past
If your hair is going to fall out, it usually begins within 2 to 3 weeks after treatment starts. It usually falls out gradually rather than suddenly.
The good news is that your hair will grow back once your chemotherapy treatment has finished. This may take 4 to 6 months. It might come back a different colour and may be more curly than before.
Find out more about hair loss and cancer treatment
Some cancer drugs can affect the way that your heart works. The drugs most likely to affect your heart are some chemotherapy drugs. The effect may be temporary but can sometimes be permanent.
Your doctor checks how well your heart works before you start treatment as well as during and after treatment ends.
Find out more about cancer drugs and the heart
Women might stop having periods (amenorrhoea) but this may be temporary.
Cancer drugs might lower your sex drive for a while. They can also be due to other reasons such as:
tiredness
stress and anxiety about having ALL
loss of confidence and self esteem
Your sex drive will usually go back to normal sometime after the treatment ends. Let your nurse or doctor know if this is worrying you.
Find out more about sex, sexuality and cancer
Tumour lysis syndrome (TLS) can be a serious complication of having cancer drugs for leukaemia. It can happen when the drugs kill large numbers of cancer cells very quickly.
When the body breaks down these dead cells they release large amounts of substances into the bloodstream. This can cause problems with your kidneys, heart and other areas of the body.
You will have frequent blood tests to closely monitor the level of:
uric acid
potassium
phosphate
calcium
If you are at risk of tumour lysis syndrome, you usually have:
extra fluids as a drip into your bloodstream
medications such as allopurinol or rasburicase to help keep the levels of uric acid in your blood stable
You are at higher risk of developing tumour lysis syndrome if you have a very high white blood cell count at diagnosis. The risk is greater at the beginning of treatment.
Your healthcare team will explain this to you before you start treatment.
Find out more about the general side effects of cancer drugs
You might develop long term side effects weeks, months or years after treatment has ended.
Some of these include:
heart problems
not being able to have children ()
early
developing another type of cancer
bone problems
diabetes
cognitive changes (chemo brain)
lung problems
thyroid problems
clouding of the eye lens (cataracts)
Different types of treatment cause different problems. And doctors can't tell who will get a long term side effect and who won't.
Because treatments have improved over the years, the treatment that people have now is less likely to cause long term problems than treatment in the past.
Find out more about the long term side effects of ALL treatment
Go to our cancer drug A to Z list to read about the possible side effects of specific cancer drugs
It can be difficult to cope with ALL and its treatment. There are medicines to help reduce side effects and other ways to help relieve them. There are also people who can support you and help you with the practical and social effects of ALL.
Some people find that talking through these issues can help them to cope.
Keeping as healthy as possible can help to reduce the chance of some problems developing. This includes not smoking, eating a well balanced diet, keeping a healthy weight and doing regular physical activity.
Talk to your healthcare team about any symptom that worries you. You don't have to wait for your next appointment.
Last reviewed: 20 Nov 2024
Next review due: 20 Nov 2027
After some types of ALL treatment, you might develop long term side effects. Some of these include problems with infertility, tiredness and cognitive changes.
The main treatment for ALL is chemotherapy. But you may also have a targeted cancer drug, immunotherapy, or a stem cell transplant. Find out how your doctor chooses your treatment, treatment side effects and follow up.
Get practical, physical and emotional support to help you cope during and after acute lymphoblastic leukaemia (ALL) treatment, including information on diet, physical activity, sex, fertility and life after a stem cell transplant.
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.
Acute lymphoblastic leukaemia (ALL) starts from young white blood cells called lymphocytes in the bone marrow. Find out about symptoms, tests to diagnose, treatments and how to cope.
Find out about childhood acute lymphoblastic leukaemia, how it is diagnosed and treated, and resources and organisations that can help you cope.

About Cancer generously supported by Dangoor Education since 2010. Learn more about Dangoor Education
Search our clinical trials database for all cancer trials and studies recruiting in the UK.
Meet and chat to other cancer people affected by cancer.
Questions about cancer? Call freephone 0808 800 40 40 from 9 to 5 - Monday to Friday. Alternatively, you can email us.