Side effects of a stem cell or bone marrow transplant

The main side effects of a stem cell or bone marrow transplant are caused by:

  • chemotherapy
  • targeted drugs if you have them

You might have extra side effects if you also have whole body radiotherapy as part of the treatment. Whole body radiotherapy is also called total body irradiation or TBI.

You may have fewer side effects if you have reduced intensity conditioning. But these can still be serious and difficult to cope with.

There are also side effects of having your transplant. For example, if you have a donor transplant there is a risk of developing a condition called graft versus host disease (GvHD).

Side effects are at their worst when you have just had chemotherapy and for a few weeks after. When your blood counts start to rise (engraftment) you will start to feel better. Let your team know if you have any side effects. They can do a lot to help you.

In the longer term, these treatments may cause infertility. This means it might be difficult to become pregnant or father a child in the future. Some people who have had a transplant do go on to have children, but this is still quite unusual. 

Risk of infection

You have a low white blood cell count after your intensive treatment. So you are at more risk of getting an infection. This can be from normally harmless bacteria that we have in our digestive system and on our skin.

To try and stop this from happening you might have:

  • antibiotics
  • anti-fungal medicines
  • mouthwashes

You need to have a shower every day to reduce the risk of infection. If you are finding it hard to shower, let your nurse know and they can help. Your room is cleaned and your bedsheets are changed every day.

Your visitors should wash their hands before they come into your room. They might need to wear gloves and aprons like the nurses and doctors. They shouldn't visit if they have coughs or colds.


You are also at risk of infection from some foods. The rules about what you can eat can be different in different hospitals. While you are an inpatient and if you need it, you have meals that are less likely to cause an infection. It can be difficult to find a balance between what you fancy eating and what might cause an infection. Your dietitian or nurse can help you with this.

When you go home you might need to take some precautions. For example:

  • heat all hot meals thoroughly and eat them fresh
  • wash and peel all fruit
  • carefully wash all salad leaves
  • avoid lightly cooked eggs
  • avoid soft cheese

Ask your medical team if you need to follow a special diet at home and how long this should be for.

Even with these precautions, you are very likely to get an infection at some point. You will need antibiotics to treat the infection.


After a transplant you lose immunity to diseases you were vaccinated against as a child. Your transplant team will let you know which vaccinations you need to have again after your treatment. It's important that all your family have the flu vaccine. And any children in your close family have their childhood immunisations.

Some pre school and primary school children have the flu vaccine as a nasal spray. If your immune system is severely weakened, you should avoid close contact with children who have had the nasal spray for 2 weeks following their vaccination. Speak to your doctor if you are not sure whether this applies to you.

Low red blood cell count (anaemia)

Your red blood cell count will fall after treatment. Your transplant team will check your red blood cell count every day. If it gets too low you might feel:

  • tired
  • lacking in energy
  • breathless

You might need a blood transfusion to top up your red blood cells. This will make you feel better almost straight away.

Sometimes people have an allergic reaction to a blood transfusion. Let your nurse or doctor know as soon as possible if you feel hot and shivery, or itchy. You will have medicines to stop the reaction. Your nurse may also slow down the transfusion rate.

More rarely, some people have:

  • chest or kidney pain (pain in your back or side)
  • a flushed face
  • chills
  • burning along the vein that your drip goes into

Tell your doctor or nurse straight away if you have any of the above. Your nurse will need to treat your reaction and might stop the infusion.

Risk of bleeding

Your platelet level will fall after your treatment. Platelets help the blood to clot. A low platelet level means you are at risk of bleeding. You might find you are bruising more easily than normal.

Tell your nurse or doctor straight away if you notice:

  • nosebleeds
  • bleeding gums when you clean your teeth
  • very heavy periods
  • blood in your urine or poo
  • bruises or small dark red spots on your skin

Your treatment team will arrange for you to have a platelet transfusion. You have the platelets as a drip into your vein. It takes about half an hour.

Sometimes people have a reaction to platelets. This is uncomfortable at the time but soon passes. Let your nurse or doctor know as soon as possible if you feel:

  • hot
  • shivery
  • itchy

Your platelet count can take a while to get back to normal after a stem cell or bone marrow transplant. It might take longer to recover if you have had your own stem cells (rather than a donor's stem cells).

Sickness and diarrhoea

You might feel sick after your chemotherapy and radiotherapy. But you should start to feel better after a couple of weeks. Other medicines, such as antibiotics, can also make you feel sick.   You can have anti sickness medicines for as long as you need them.

Diarrhoea can be caused by:

  • chemotherapy and radiotherapy
  • infection
  • graft versus host disease (GvHD)

Tell your team if your diarrhoea is severe. They will give you medicine that will help. You will also need treatment for the underlying cause of the diarrhoea.

A sore mouth

A sore mouth and mouth ulcers are very common after a transplant. You can have mouthwashes and lozenges to suck to try to prevent infection. Ask for painkillers if you need them. Sucking on ice cubes can sometimes help to reduce the pain.

Difficulty eating and drinking

You won't have much appetite just after your transplant. 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. Or you might have liquid nutrition through a tube into your tummy or through your central line.

Feeling tired and run down

You will feel very tired and run down after your transplant. This will be at its worst during the second and third weeks when your blood cell counts are at their lowest.

Slowly you will feel that you have more energy. But you will feel more tired than usual for quite a long time after your transplant. This could last for up to a couple of years.

Loss of fertility

A longer term side effect of a transplant is infertility. This means you will no longer be able to become pregnant or father a child naturally. This is caused by total body irradiation and the high doses of chemotherapy in full intensity conditioning.

Some people who have had a transplant do go on to have children naturally, but this is unusual. Sometimes it is possible for men and teenage boys to store sperm before they start their chemotherapy. This is called sperm banking.

Treatment can cause an early menopause for women. You might have hormone replacement therapy (HRT) to help with the symptoms. Some women are able to store embryos or eggs before starting cancer treatment, but this is not always possible. Research is going on all the time to try to help women have children after cancer treatment.

Graft versus host disease (GvHD) with a donor transplant

If you have had a transplant from a relative or a matched unrelated donor, you are at risk of GvHD. This is because the donor stem cells contain immune cells from the donor. These cells can sometimes attack some of your own body cells.

GvHD can cause:

  • diarrhoea
  • weight loss
  • yellowing of the eyes and skin (jaundice)
  • sore eyes or mouth
  • skin rashes
  • shortness of breath

GvHD can be severe and even life threatening for some people. But mild GvHD can also be helpful for some. It is an immune system reaction and can help to kill off any cancer cells left after your treatment.

Let your healthcare team know if you have any signs of GvHD. You can have treatment with immunosuppressant drugs to help reduce the reaction.

  • The European Blood and Marrow Transplantation Textbook for Nurses. Under the Auspices of EBMT
    M Kenyon and A Babic (Editors)
    Springer Open, 2018

  • Late effects of blood and marrow transplantation
    Y Inamoto1 and SJ Lee
    Haematologica, 2017. Volume 102, 4, pages 614–625

  • Infection-control interventions for cancer patients after chemotherapy: a systematic review and meta-analysis
    A Schlesinger and others
    The Lancet - Infectious Diseases, 2009. Volume 9, Issue 2, Pages 97-107

  • Diagnosis and management of chronic graft-versus-host disease
    F Dignan and others
    British Journal of Haematology, 2012. Volume 158, Pages 46-61

  • Diagnosis and management of acute graft-versus-host disease
    FL Dignan and others
    British Journal for Haematology, 2012. Volume 158, Pages 30-45

  • The information on this page is based on literature searches and specialist checking. We used many references and there are too many to list here. Please contact with details of the particular issue you are interested in if you need additional references for this information.

Last reviewed: 
29 Nov 2022
Next review due: 
28 Nov 2025

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