Managing side effects of cancer treatment

Chemotherapy treatment can cause different side effects. The side effects you get will depend on the chemotherapy drugs you are having. We have listed some common side effects below and advice on how to manage them.


Nausea and vomiting

Some chemotherapy drugs will make you feel sick (nauseas) or cause you to be physically sick (vomit).  In most cases anti sickness medicines, known as anti-emetics will be given to you prior to your chemotherapy.

It is important to take these medications on time and as prescribed, so that they can work in the most effective way. Setting an alarm or keeping a log of when certain medicines are due can help give you a sense of control. It can also help to keep a record of timings of when nausea and vomiting is worse.

If vomiting persists for more than 24 hours, and doesn’t improve, contact your clinical team or your registered GP, as prolonged vomiting can lead to dehydration and a dip in blood sugar levels. There are a wide range of different types of anti-sickness medications that can be prescribed by your doctor, and it may be a matter of finding the best combination for you.

For further help and information please contact the patient helpline:

Monday to Friday 8.30am - 5pm:  07833 435 950 or 07795 612 236

Outside of these times and on bank holidays, please call: 020 7188 3754


Coping with a small appetite

Loss of appetite during cancer treatment is very common and can be related to the physical effects of cancers, or the side-effects of your surgery or treatment. Often a loss of appetite can make it difficult to eat as much as normal and can result in weight loss.

When your appetite is low or you have lost weight without trying you may need to make different food choices to what you are used to. When you are eating less, it is important to make sure what you do eat is as high in nutrients, calories (energy), and protein as possible. This can help to avoid weight loss and help you feel as well as you can.

Tips for coping with a small apetite:

  • Keep a food diary so that you can assess better and worse days. It is helpful to bring this to appointments with your clinical team

  • Set an alarm to remind you to eat

  • Eat less and more frequently.

You can speak to your Clinical Nurse Specialist or clinical team for referral to dietician.

More information is available on our nutrition and eating well page.


Sore mouth and throat

If eating and drinking is painful, or you are experiencing an uncomfortably dry mouth during or following cancer treatment, speak with your clinical team. They may be able to recommend or prescribe mouthwashes or medications such as artificial saliva to help ease the discomfort. Some of these are best taken 20-30 minutes before eating but always follow the advice of a healthcare professional.


Changes in taste

Some chemotherapy drugs and cancer treatments interventions can alter taste. Previous food preferences may change but in most cases this will pass. 


Changes in bowel habit

Change of bowel habit during cancer treatment can be caused by some chemotherapy drugs, or can be a side effect of your surgery.

If you are concerned about diarrhoea or constipation please discuss this with your clinical team or GP.


Further information

The Macmillan website is updated regularly with information and advice about chemotherapy side effects.