Potential side effects

Most transplant side effects are caused by having low numbers of blood cells. Your team will monitor you and tell you what to expect. Side effects include increased risk of infection, anaemia and bruising or bleeding. Your blood will be tested every day to check your blood count. Side effects improve as you make new blood cells.

You usually stay in a single room to protect you from infection. The nurses will help you and give you advice on hygiene, mouth care and foods to avoid because of the risk of infection. You will be given drugs to prevent and treat infection and to reduce other side effects.

Other side effects include:

  • tiredness
  • sickness and diarrhoea
  • hair loss.

Some less common problems may happen later after the transplant. Because your immune system isn’t working well you are at more risk of viral infections. You will have blood tests to check for this.

If you still have some of your own blood cells after transplant, you may need white cells from your donor to destroy them. This is called a donor lymphocyte infusion.

The side effects of treatment

The side effects will depend on the type of conditioning treatment you had. People having a reduced-intensity transplant may have less severe side effects. Your transplant team will tell you more about what to expect.

Most side effects are caused by having low numbers of blood cells. This will gradually improve as you start making new blood cells. You will have your blood tested every day to check your blood count.

You will be given drugs to prevent or reduce side effects. Always let your nurse or doctor know about the side effects you have. There are often ways they can be controlled or helped.

Risk of infection

The number of white blood cells (your neutrophils) will be very low for some time. This is called being neutropenic. Neutrophils are very important in fighting infection.

During this time, you are at risk of infection, even from the normal bacteria that live on your skin and in your digestive system. These bacteria are usually useful to our bodies but can cause infections when your immune system is not working well.

You will be given drugs to prevent and treat infections. Your nurses and doctors will take your temperature regularly and check for signs of infection. They will also ask you to tell them if you have symptoms that could be a sign of infection. These include:

  • feeling cold and shivery
  • having a sore throat
  • having a cough or runny nose
  • pain when passing urine.
  • having diarrhoea

The hospital staff try to protect you from possible infections. But most people will need antibiotics at some point while their immune system is recovering.


You will usually stay in a single room with your own toilet and shower to protect you from infection. This is sometimes called protective isolation. Sometimes the room may have a special air conditioning system to keep the air in your room very clean.

Your room, toilet and shower are cleaned every day. Your bed sheets will also be changed every day.

Your nurse will give you advice about personal hygiene, such as showering and washing your hands. They can help you with this if you are feeling very tired. They also show you how to look after your mouth.

Being careful with food

During your time in hospital, there will be rules about what you can eat. This is to help you avoid food that may contain bacteria. Each hospital has its own guidelines. Your nurse or dietitian can explain them to you.

The rules may include:

  • Avoid soft cheeses, pâté and unpasteurised foods.
  • Do not eat lightly cooked or uncooked eggs.
  • Wash and peel fruit and vegetables.
  • Hot meals should be freshly prepared and well cooked (not reheated).
  • Avoid probiotic or bio foods, drinks or supplements.
  • Avoid takeaway foods.


Hospitals may have different rules about visitors. You may be restricted to only a few visitors each day. The ward nurses will tell your visitors how to help protect you from infections. For example, they must wash their hands before going into your room and may be asked to wear a plastic apron. People who feel unwell or have an infection should not visit you.


The number of red blood cells in your blood will be low at times. This is called anaemia. It can make you feel tired and short of breath. You may need blood transfusions until your body starts to make enough red blood cells again.

Irradiated blood

For several months after your transplant, any blood or platelet transfusions you are given are first treated with radiation (irradiated). This is to prevent problems caused by white blood cells called lymphocytes, which are in the donated blood. Irradiated blood is not radioactive and will not harm you or anyone you come into contact with.

Some people may need any blood or platelet transfusions to be irradiated for the rest of their lives. Your doctor will talk to you about this. You will be given a medical alert card to carry in case you need blood in an emergency.

Bruising and bleeding

The number of platelets which help the blood to clot will be low after the transplant. You are likely to need platelets as a drip (infusion) to reduce the risk of bleeding or bruising. The platelets will be irradiated before they are given to you.

The doctors and nurses will examine you regularly for bruises or little red spots on the skin (petechiae). Let them know straight away if you have a nosebleed, bleeding gums or notice blood in your stools (bowel motions) or urine.

Tiredness (fatigue)

You will probably feel extremely tired and spend a lot of time sleeping. Sometimes you may feel too tired to concentrate on reading or even watch television.

At times, you may not feel able to have visitors, or see them for too long. Let them know how you are feeling so they do not disturb you if you want to rest.


Even though you are tired, it is a good idea to try to do some gentle exercise, such as stretching. A physiotherapist will show you how. This helps reduce the chances of getting a blood clot, and it keeps your muscles working and toned.

Some transplant units may have an exercise bike that you can use when you are feeling better and your blood counts have improved.

Feeling sick

The nurses will give you anti-sickness drugs (anti-emetics) regularly. If you still feel sick, tell your nurse or doctor. They can change the anti-sickness drug to one that works better for you.

Sore mouth

The treatment can cause a sore mouth and throat. You may also get painful mouth ulcers. The nurses will show you how to look after your mouth and teeth to reduce the risk of side effects. They will check your mouth regularly. If your mouth is sore, your doctor will prescribe painkillers to help. You may be given gels that can help.

Keeping your mouth clean is very important to prevent infections. Gently clean your teeth or dentures in the morning, at night and after meals. Use a soft toothbrush. You may be given mouthwashes to take, or asked to rinse your mouth regularly. Follow any advice you are given and drink plenty of fluids.

Eating difficulties

Treatment causes different side effects that can make eating difficult. These may include a sore mouth, sickness, loss of appetite or taste changes.

The nurses will give you advice, and you may also talk to a dietitian. It is important you do not lose too much weight. They will encourage you to try to eat small meals and snacks. You may need drinks that give you extra calories and nutrients until you can eat properly again.

If you lose too much weight, you may need extra support to get the nutrition you need. This may involve having liquid food through a thin, soft tube that goes up the nose down into the stomach. Or, some people may be given specially prepared nutrition into a vein through their central line.

Hair loss

This is a common side effect of chemotherapy. You usually lose all the hair on your head. Your eyelashes, eyebrows and other body hair may also thin or fall out. It is almost always temporary and your hair will grow back after chemotherapy ends. Your nurse can give you advice about coping with hair loss. After treatment, it is important to cover your head to protect your scalp when you are out in the sun until your hair has grown back.


This can sometimes be severe. You will be given drugs to control diarrhoea. The nurses will take samples to check for an infection, and you will be given antibiotics if you need them.

Try to drink at least two litres (three and a half pints) of fluids every day. Some people may need to have fluids through a drip until the diarrhoea improves. Let the nurses know if it does not get better, or if the skin around your bottom gets sore.

Bladder irritation

Some chemotherapy drugs may irritate your bladder and cause discomfort when you pass urine. You may be given fluids through a drip (infusion) and some drugs to help prevent bladder irritation. Drink at least two litres (three and a half pints) of fluids each day. It is also important to empty your bladder regularly and try to pass urine as soon as you feel the need to go.

Tell your doctor or nurse straight away if you feel any discomfort or stinging, or if you notice any blood when you are passing urine.

Effects on the lungs

Treatment can sometimes cause changes to the lungs. This is more likely if you already have lung problems. Always tell your doctor if you notice wheezing, a cough, or feel breathless. You should also tell them if any of these problems get worse.

Treatment may also cause side effects that develop months or years after treatment. These are called late effects.

Virus infections

There are some other less common problems that may happen after the transplant. Your doctors and nurses will monitor you closely for any of these complications.

Because your immune system is not working well, you are more at risk from infections caused by different viruses. Some viral infections you had before may become active again. Your doctors will check for certain viruses that may cause more serious problems.

Cytomegalovirus (CMV)

Most people will have had CMV by the time they are an adult. It rarely causes symptoms, so you will not usually know you have had it. It stays in your body and your immune system keeps it under control. This means it is not active and does not cause problems. But if your immune system is weakened, the CMV virus may become active again and cause problems.

Before your transplant, you and your donor are checked for CMV. If you are CMV negative doctors try to match you with a donor who is the same.

After your transplant, even if you have not had CMV, you have regular blood tests to check for it. People who have not had CMV may catch it after transplant.

Doctors monitor CMV levels carefully to pick up changes early. If levels start to rise quickly after your transplant or become too high, you may need treatment. This is usually with tablets or sometimes drugs through a drip.

Epstein-Barr Virus (EBV)

Most people have EBV at some time during their lives, but it can become active again after a transplant. If EBV infection gets out of control, there is a very low risk it may lead to developing another cancer after transplant. Because of this, you have regular blood tests to check for EBV and treatment if needed. Your doctor will tell you more about this.


All blood in the UK is screened for hepatitis B and C. People having a donor stem cell transplant now have blood or platelet transfusions checked for hepatitis E virus (HEV).

HEV is not easily passed from person to person, but it can be passed on through a blood transfusion. It can also be present in pork products, shellfish and other meat. Look at our advice on eating and drinking after you go home.

HEV is usually a very mild infection that goes away by itself. But if your immune system is weak, it may not be able to get rid of it. So over time it may lead to liver problems.

Donor lymphocyte infusions (DLI)

There are some other less common problems that may happen after the transplant. Your doctors and nurses will monitor you closely for any of these complications.

People who still have some of their own blood cells (called mixed chimerism) after transplant may need an infusion (drip) of white blood cells from their original donor. This is called a donor lymphocyte infusion.

Chimerism is a word doctors use to describe how well your donor’s cells have engrafted. After transplant, the aim is for total chimerism (100%). This is when all your blood and bone marrow are from your donor.

Mixed chimerism means some of your own cells are still there. This is more likely if you had reduced-intensity conditioning. Because you had lower doses of chemotherapy, some of your own blood cells survive.

Sometimes mixed chimerism gradually improves on its own. If it does not get better, doctors can treat it by giving you white blood cells (lymphocytes) from your donor. The donor white cells destroy any of your remaining cells. The aim is to increase the chimerism level to 100%.

The lymphocytes are given to you by a drip into your line. If these cells were not saved when your donor had their first collection, they can donate more cells. They will not need injections of growth factors for this. The lymphocytes are collected in the same way as the stem cells were.

The main risk of a donor lymphocyte infusion is that you might develop GVHD. Your doctor will talk to you about any risks.

Starting to recover

When your blood count has reached a safe level, you’ll be able to go home, as long as a relative or friend stays with you. You’ll be given a 24-hour telephone contact number in case you have any worries. You’ll need to go back to the hospital regularly as an outpatient for check-ups.

How you can help yourself

Being involved in your care can help you feel more in control. You could try to:

  • Get up every day, have a shower and change your clothes.
  • Eat regularly even if you don’t have much of an appetite.
  • Do any exercises you have been shown and walk around your room. When your blood counts are up, you might be able to take short walks around the unit. Some units have exercise bikes you can use.
  • Ask for regular updates on your progress and record it in a notebook or on your phone.

Understanding your illness and treatment makes it easier to cope with. If there is anything you do not understand about your treatment, its side effects and possible outcomes, it is important to ask. Tell the doctors and nurses if you have new side effects or changes in your mood.

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