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Late side effects of chemotherapy

Most chemotherapy side effects are temporary and disappear once your treatment is over. For some people chemotherapy can cause long term changes in the body months or years after treatment.

Many people feel more tired than usual for a long time after chemotherapy treatment. This is most likely to happen after a lot of treatment, or very intensive treatment. For example, after high dose chemotherapy or if you are having a bone marrow or stem cell transplant. 

After intensive treatment, you are likely to have a lower resistance to infection for quite a long time. This will gradually get back to normal, but can take some months.

In some cases chemotherapy can cause infertility.

Problems with different organs

Some chemotherapy drugs can cause long term problems with specific body organs. 

There are drugs that can cause heart damage or lung damage. But cancer doctors are aware of this. You will have tests before and during your treatment so your doctor can keep an eye on your reaction to the drug.

There may be some chemotherapy drugs your doctor won't use, if you have a heart condition. Your doctors will also check you for these effects for some years after your treatment.

Second cancers

A long term side effect of some drugs is a risk of getting another cancer in the future. This is called a second cancer.

For your own peace of mind, it is important to remember that this is a very small risk, and only occurs with some chemotherapy drugs. Your doctor will talk to you about the specific risk with the drugs you are having. The risk of a second cancer is less of a risk to you than the cancer you are having treatment for.

Chemo brain

After cancer treatment, some people notice changes in their memory, concentration and the way they think. These changes are called mild cognitive impairment (MCI) or cognitive dysfunction. Some people call them 'chemo brain' or 'chemo fog'.

It's not clear exactly what causes these memory and concentration changes in people with cancer. So calling them chemo brain may not be accurate.

Its possible that these problems might be due to other cancer treatments. Or more recent research has shown that some people with cancer have similar problems before they start any treatment. So these changes could be due to the cancer itself. 

Researchers are trying to find out:

  • what causes chemo brain
  • how health professionals and people with cancer can best manage the symptoms of cognitive impairment

What to do if you are worried

There are many different chemotherapy drugs and they all have different side effects. Ask your doctor or specialist nurse about the drugs you are having if you are worried about long term effects from your treatment.

The National Survivorship Initiative (NCSI) is a partnership between NHS England and Macmillan Cancer Support. They are looking at the issues people have when they finish cancer treatment, including long term side effects, so that they get the support they need to lead as healthy and active life as possible.

Last reviewed: 
17 Nov 2017
  • Electronic Medicines Compendium

    Accessed, 2015

  • Handbook of Cancer Chemotherapy (8th edition)
    R T Skeel and S N Khleif
    Lippincott, Williams and Wilkins, 2011

  • Handbook of Systemic Treatments for Cancer (8th edition)

    L Doughtery, A McWhiter and P Jones

    Lilly Oncology 2014

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