Side effects of a stem cell transplant

Side effects can happen with any type of treatment, but everyone’s experience is different. Some people may have many side effects. Others have fewer.

Side effects can happen any time during, immediately after or days to months after a stem cell transplant. Short-term (acute) side effects generally develop during the first 100 days after a stem cell transplant. Long-term (chronic) side effects generally develop 100 or more days after the transplant. Most side effects go away on their own or can be treated, but some side effects can last a long time or become permanent.

Side effects of a stem cell transplant will depend mainly on:

  • the type and dose of chemotherapy drugs used as conditioning therapy before the transplant
  • the dose of radiation therapy if it was given before the transplant
  • the type of transplant done
  • how good a match the donor stem cells are
  • your age and overall health

A stem cell transplant is very complex. It can take 6 to 12 months or longer for your blood counts to be back to normal and your immune system to work well. Side effects of a stem cell transplant can be very serious or even life-threatening. The healthcare team will watch you closely during this time. They will take measures to prevent side effects and will quickly deal with any side effects that develop.

Children usually have less severe side effects than adults and will often recover from them faster. But it’s hard to say exactly which side effects a child will have, how long they will last and when the child will recover.

Many common side effects, such as nausea, vomiting, fatigue and temporary hair loss, are from the chemotherapy or radiation therapy given before the transplant. Other side effects are related to the stem cell transplant.

Low blood cell counts

You will have low blood cells counts after a stem cell transplant. It takes time for stem cells to make their way to the bone marrow and start making new blood cells (called engraftment).

  • A low white blood cell count (neutropenia or leukopenia) increases the risk for infection.
  • A low platelet count (thrombocytopenia) increases the risk for bruising and bleeding.
  • A low red blood cell count (anemia) causes fatigue, dizziness, shortness of breath and malaise.

You will have daily blood tests to check the number of different types of blood cells until doctors see a steady increase in blood cell counts.


Infection is one of the most common early side effects of a stem cell transplant. It happens because the white blood cell count is very low and the immune system is weak. Bacterial infections are most common. Viral or fungal infections can also happen.

The risk of infection for all types of transplant is high until the bone marrow starts to make white blood cells. The risk is highest after an allogeneic transplant because you may be taking medicines to suppress the immune system to prevent graft-versus-host disease (GVHD).

Infection can also happen a long time after a stem cell transplant. The risk of late infection depends on how quickly your immune system recovers, whether you have GVHD and if you are taking medicines to suppress your immune system.

Fever is often the first sign of infection. Even if there is no sign of infection, most people are given medicines to prevent infection until their white blood cell counts start to rise. Doctors may also prescribe a colony-stimulating factor (CSF) such as filgrastim (Neupogen) following a stem cell transplant to help lower the risk of infection and speed up the process of making new blood cells.


Bleeding can happen after a stem cell transplant because the platelet count is very low and it reduces the blood’s ability to clot. Some people get serious bleeding problems (hemorrhage). If the red blood cell count is too low, it can lead to anemia. You may need platelet transfusions until the transplanted stem cells start to work, especially during the first month after the transplant.


Anemia is a low red blood cell count and a lower concentration of hemoglobin in blood cells. Hemoglobin is the part of the red blood cell that carries oxygen. When hemoglobin levels are low, body tissues don’t get enough oxygen and can’t work properly. Colony-stimulating factors, such as epoetin alfa (Eprex, erythropoietin) or darbepoetin (Aranesp), may be given to help increase red blood cell counts. If the red blood cell count is too low, blood transfusions may be needed.

Graft-versus-host disease (GVHD)

Graft-versus-host disease (GVHD) might happen after an allogeneic stem cell transplant. Healthy stem cells from the donor (person who gives the stem cells) attack the cells of the recipient (person receiving the stem cells). The cells from the donor see the recipient’s cells as foreign and start to destroy them. GVHD can permanently damage an organ.

You may have to take immune-suppressing drugs for months or years after an allogeneic transplant to prevent or treat GVHD.

Veno-occlusive disease (VOD)

Veno-occlusive disease (VOD) happens when small blood vessels that lead to the liver become blocked. VOD is more common after an allogeneic transplant. It can develop in the first few weeks after a stem cell transplant and can lead to liver damage.

Symptoms include jaundice, tenderness of the liver and fluid buildup in the abdomen. Medicine may be used to prevent or treat VOD.

Digestive system problems

Digestive problems happen because tissues in the mouth, stomach and intestines are sensitive to the chemotherapy drugs given before the transplant. Digestive problems can also be caused by infection, GVHD or side effects of medicines.

Digestive system problems include:

Your healthcare team may give you special mouthwashes or lozenges and pain medicines for a sore mouth. They will also talk to you about good mouth care during and after treatment. You may have medicines to control diarrhea, nausea and vomiting.

If you have trouble eating, the healthcare team may suggest that you eat small meals and snacks instead of big meals or take food supplements.

For severe eating problems, you may be given nutrition through the central venous catheter (tube). This is called parenteral nutrition or total parenteral nutrition (TPN).

Skin and hair problems

The therapy given before the transplant and GVHD can cause skin problems. This side effect is common when certain chemotherapy drugs and total body irradiation (TBI) are used. Skin problems include rashes, itching, blisters and peeling skin. The healthcare team will tell you how to care for your skin. Medicated creams or ointments and other medicines may be given to help manage skin problems.

Temporary hair loss can also happen after therapies given before the transplant. Hair loss is rarely permanent. It usually grows back within 3 to 6 months after the transplant.


Pain occurs when tissues or nerves are inflamed. Pain can be caused by the chemotherapy and radiation therapy given before the transplant and by infection, medicine, mouth sores and skin problems.

Pain medicines and other therapies, such as relaxation or visualization, are used to help relieve pain. The healthcare team will help prevent and manage your pain.

Kidney problems

Kidney problems can happen when the kidneys are damaged by chemotherapy drugs given before the transplant, by antibiotic therapy or by medicine used to suppress the immune system. Sometimes kidney problems become so serious that they can lead to kidney failure, which is a long-term problem.

To prevent kidney problems after a transplant or to treat kidney problems that happen, your healthcare team may limit the amount of fluids you drink and change some of your medicines. The healthcare team will closely check the amount of fluids you take in and put out as urine. They will take measures to prevent and reduce damage to the kidneys as much as possible during treatment.

Lung problems

Lung problems can happen when the lungs are damaged by the chemotherapy and radiation treatments given before the transplant, by infection or by drinking too much fluid after the transplant. Lung problems are common in people with GVHD and include the following:

  • Pulmonary edema is a buildup of fluid in the lungs that causes shortness of breath.
  • Pneumonia is infection of the lungs caused by bacteria, viruses or fungi.
  • With restrictive lung disease, the lungs can’t expand fully when you breathe in. It is hard to take a full breath and can be a long-term problem.
  • With obstructive lung disease, the airway is blocked. It is hard to empty all the air from the lungs when you exhale, and air is left in the lungs. It can be a long-term problem.

The healthcare team will check you with chest x-rays and lung function tests. You may be given medicines to prevent infection after the transplant or to treat lung problems if they develop.

Heart problems

Heart problems are not common after a stem cell transplant but they can happen. Certain chemotherapy drugs given before the transplant can cause the heart not to work as well. They can also cause the tissue around the heart to become inflamed (called pericarditis).

A multigated acquisition (MUGA) scan to check how well your heart is working and assess any damage to the heart muscle is often done before chemotherapy is given. Chemotherapy drugs that are less damaging to the heart may be used before a stem cell transplant. Medicines can be used to treat heart problems that develop after a transplant.

Central nervous system (CNS) problems

The central nervous system (CNS) is made up of the brain and spinal cord. Brain tissue can be damaged by radiation treatments given before a stem cell transplant, by chronic GVHD, by infection or by a return of the cancer.

CNS problems can develop months or years after a stem cell transplant. CNS problems can include damage to the brain that results in problems with mental (cognitive) function. Other CNS problems include:

  • sleepiness
  • poor concentration
  • memory problems
  • problems learning new tasks
  • confusion and disorientation
  • loss of balance and fine motor control

Report changes in your mental function to the healthcare team. You may see a neurologist and have therapy to help with these changes.

Eye problems

Eye problems usually develop a year after a stem cell transplant, but they can also happen several years later. Eye problems can happen if total body irradiation is given before a stem cell transplant. Chemotherapy and steroids may also increase the chance of developing eye problems.

The most common eye problem is cataracts. A cataract clouds the lens of the eye and can cause vision loss. You will be encouraged to have regular eye exams and report any vision changes. Cataracts are removed with surgery.

Another eye problem is ocular GVHD. It causes eye dryness with a gritty or sandy feeling. Ocular GVHD is treated with eye drops for comfort and to help the eyes produce tears. You may also be given medicine to prevent infection.

Bladder problems

Bladder problems can happen when chemotherapy and radiation treatments given before the transplant scar the bladder wall. This can lead to frequent urination, blood in the urine and bladder spasms. Drugs that suppress the immune system can cause recurring bladder infections. You may be given medicines to decrease bladder spasms and treat infections. You will be encouraged to drink extra fluids.

Thyroid problems

The risk of developing thyroid problems is quite high when total body irradiation is used before a stem cell transplant. Hypothyroidism is the most common thyroid problem. This is where the thyroid does not make enough thyroid hormone. Symptoms of hypothyroidism include fatigue, weight gain, hair loss, brittle nails, dry skin and feeling cold.

For adults, thyroid function may be checked each year after a stem cell transplant. Some people may need thyroid hormone replacement therapy if the thyroid doesn’t make enough thyroid hormone.

If children do not have enough thyroid hormone, it slows their physical and mental development. It usually develops a few years after treatment and can become a long-term problem. The thyroid function will be checked often. Some children may need thyroid hormone replacement every day to regulate the thyroid gland.

Developmental problems

In children, total body irradiation can cause long-term developmental and growth delays. This can happen because radiation to the head affects the hypothalamus in the brain. The hypothalamus controls the release of growth hormones. Low levels of growth hormones will result in shorter height, shortened limbs and less overall physical development. Steroid medicines and GVHD can also affect growth. Treatment with growth hormones may be needed.

Fertility problems

Fertility problems can happen because of chemotherapy or radiation therapy given before a stem cell transplant. When the reproductive organs (gonads) stop working, it is called gonadal dysfunction.

Children receiving treatment, especially those close to or during puberty, have the greatest chance of having long-term or permanent gonadal dysfunction, called gonadal failure. Children treated before puberty have fewer problems with reproductive organ function and fertility.

Most women who have a stem cell transplant will experience treatment-induced menopause. Men and women may regain gonadal functioning and fertility, but gonadal dysfunction may become permanent and cause infertility.

Hormone replacement therapy may be given for gonadal dysfunction.

Talk to your healthcare team about fertility problems. They can suggest ways to help women cope with symptoms of menopause. They can also provide information about ways you can preserve your fertility. Women may choose to freeze and store fertilized eggs (embryos) to be implanted after the transplant and recovery. Men may choose to freeze and store their sperm for future use.

Liver problems

Liver problems that can develop include veno-occlusive disease (VOD), graft-versus-host disease, infection or damage due to the medicines given before the transplant. Treatment is supportive and includes medicines for VOD, infection and pain. If kidney function is also affected, treatment includes limiting the amount of fluids you drink and changing some medicines.

Oral and dental problems

Graft-versus-host disease is the most common cause of late oral and dental problems. Symptoms range from mild tenderness of the mouth, throat, esophagus and stomach to severe pain. Decreased saliva production results in tooth decay (cavities). Infections can also contribute to oral problems.

Mouth rinses, steroid dental pastes and medicines are used to treat oral and dental problems. You will be taught about careful and thorough care of your teeth and mouth. You will be encouraged to have regular visits to your dentist. You may be given fluoride treatments to help prevent cavities.

Graft failure

Primary graft failure means that transplanted stem cells have not started making new blood cells in the first 3 to 4 weeks after the transplant. Treatment for primary graft failure is a second stem cell transplant.

Secondary graft failure happens after new blood cells start appearing. Treatment includes a combination of growth factors such as erythropoietin and G-CSF. If an allogeneic transplant has been done, medicines to suppress the immune system are stopped. Lymphocytes from the donor or a second transplant may be needed.

Graft rejection

Graft rejection (stem cell rejection) happens if the body rejects the transplanted stem cells. This is more common in allogeneic transplants, especially when the donor is unrelated or less well matched. Graft rejection may be treated with growth factors. Sometimes a second transplant can be done.


Osteoporosis is a loss of bone density. It makes the bones weak. It can develop late after a stem cell transplant because of medicines, gonadal dysfunction or lack of physical activity. Treatment includes taking extra vitamin D and calcium. Medicines called bisphosphonates may be given for severe osteoporosis. Women who have treatment-induced menopause may consider hormone replacement therapy to keep bones from becoming weaker.

Quality of life

Quality of life can be greatly affected by the problems caused by the transplant, the long-term side effects and the medicines needed to treat some of the long-term effects.

Some factors that can affect quality of life include depression, anxiety and changes in body image. Relationships with your family and friends can be affected by the stress of having cancer and getting a stem cell transplant for cancer. Also, the duration of the transplant and the long time it takes to recover may make you feel socially isolated.

Transplant centres and hospitals often have plans of care that will improve quality of life, including education for you and your family. Counselling about your work, rehabilitation programs, support groups and psychological counselling may help decrease the negative effects on quality of life.

Second cancers

Other cancers can develop because of the amount of chemotherapy and radiation therapy given before the transplant.

  • Myelodysplastic syndrome (MDS) can happen after an autologous stem cell transplant. MDS can also lead to acute myelogenous leukemia (AML).
  • A second solid organ cancer (such as melanoma, sarcoma or brain cancer) happens more often after an allogeneic stem cell transplant.
  • Post-transplant lymphoproliferative disorder (PTLD) can happen after both autologous and allogeneic transplants and most often happens after a solid organ transplant.

The chance of getting a second cancer increases over time. Doctors will check for a second cancer at all follow-up appointments.

Expert review and references

  • American Cancer Society . Stem Cell Transplant for Cancer . 2016 :
  • Anderson-Reitz L . Complications of hematopoietic cell transplantation. Yarbro CH, Wujcki D, Holmes Gobel B, (eds.). Cancer Nursing: Principles and Practice. 8th ed. Burlington, MA: Jones and Bartlett Learning; 2018: 18: 591 - 609.
  • British Columbia Ministry of Health . HealthLink BC: Allogeneic Stem Cell Transplant . 2016 :
  • US National Library of Medicine. MedlinePlus Medical Encyclopedia: Bone Marrow Transplant. 2016:

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