Side effects of cancer treatment

Treatment side effects vary depending on the type of cancer you have, the stage of the cancer, and the type of treatment you are given. The changes can be both physical and emotional. Some side effects resolve quickly; others can take weeks, months or even years to improve.

Your body will cope with the treatment and recovery in its own way. Try not to compare yourself to others. You should talk to your doctor or nurse about possible side effects before your treatment begins. It is important to know what to watch out for or report, and who to contact out of hours if you have immediate concerns.


Fatigue is when you feel very tired, weak, drained and worn out. Cancer-related fatigue is different to normal tiredness because it doesn’t always go away with rest or sleep. Research shows that most people experience fatigue after a cancer diagnosis.

Fatigue can include having little or no energy, muscle aches and pains, weakness or slowness, trouble thinking clearly or concentrating or not being able to do daily tasks.

Fatigue can last throughout the cancer treatment and for some time after it is finished. Energy levels usually improve over time. Feeling fatigued does not usually mean the cancer has advanced. If you are concerned, speak to your doctor or call 13 11 20
Tips for managing fatigue:

  • Plan a loose daily schedule or routine based on how you are feeling and save your energy for what you want or need to do most.
  • If you can, ask family, friends or neighbours to help you.
  • Pace yourself. Try to attend to one thing at a time and include regular short breaks throughout the day. Rest when you need to.
  • Try relaxation or meditation techniques.
  • Be physically active – ask your health care team how to exercise safely for your situation.
  • Eat as well as possible, drink lots of water and avoid smoking and alcohol.

See our factsheet for more information about Fatigue and Cancer

Thinking and memory

Some people diagnosed with cancer notice changes in the way they think and remember information. This is called cancer-related cognitive impairment, but people may also refer to it as “cancer fog” or “chemo brain”.

People with cancer often report a noticeable or sudden decline in cognitive function. Cognitive problems can occur before, during or after cancer treatment. Some people notice small or subtle changes, but for others the effects are more obvious.

Dealing with cancer-related cognitive impairment can be challenging. You may not feel like yourself, which can affect your relationships with your family, friends and colleagues.

See our factsheet for more information about Understanding Changes in Thinking and Memory.

Hair loss

Many people having chemotherapy and radiation therapy worry about hair loss. Some people lose all their hair quickly, others lose it after several treatments, or others may only lose a little hair or none at all. Not all cancer treatment causes hair loss.

Chemotherapy may cause the hair on your head to break off at or near the scalp. Shortly before the hair falls out you might feel some scalp irritation, discomfort or itchiness. You may notice fallen hair on your pillow and sheets and when you brush your hair or wash it. The hair may fall out over a very short period of time (days). It is common for hair loss to begin two or three days after starting treatment. Although losing head hair is most common, you may also lose hair from your eyebrows, eyelashes, arms, legs, chest and pubic region.

If you have hair loss, you may experience a range of emotions including anger, anxiety and acceptance. Some people may feel self-conscious about their appearance and other people find that it is not as bad as they expected. Experiencing a variety of feelings and reactions is very common.

Tips for managing hair loss:

  • Use a gentle shampoo and conditioner.
  • Gentle massage and moisturising of the scalp using a non-perfumed lotion or emollient can help reduce flaky areas.
  • You may like to wear a soft cap, beanie tor turban to keep your head warm.
  • Use a pillowcase made from a smooth fabric such as poly-cotton, cotton sateen or bamboo. If you prefer to leave your head bare, protect it against sunburn and the cold.

We offer a Wig and Turban service for all cancer patients free of charge. Call 13 11 20 to find out more.

See our factsheet for more information on Hair Loss

Peripheral neuropathy

Peripheral Neuropathy is damage to the peripheral nerves. These are the nerves located away from the centre of the body, such as in the hands and feet.

Some types of chemotherapy that  are used to treat cancer can damage the peripheral nerves. If this side effect occurs, your may hear it called chemotherapy-induced peripheral neuropathy. Sometimes, other cancer treatments and the cancer itself can cause peripheral neuropathy.

If you are having chemotherapy that has a high risk of causing nerve damage, your treatment team will monitor you closely for early signs of peripheral neuropathy. In other cases, it may be diagnosed after you report symptoms to your cancer specialist or GP.

If your doctor suspects that you have peripheral neuropathy, they will check how the symptoms affect your daily life and may ask you to complete a symptom checklist. The doctor may check your;

  • awareness of where your body is
  • reflexes
  • balance and coordination
  • blood pressure

See our factsheet for more information on Understanding Peripheral Neuropathy and cancer.


Lymphoedema is swelling (oedema) that develops when lymph fluids build up in the tissues under the skin or sometimes deeper in the abdomen and chest areas. This happens because the lymphatic system in not working properly in that part of the body. It usually occurs in an arm or leg but can also affect other parts of the body. Lymphoedema can be either primary (when the lymphatic system has not been developed properly) or secondary.

Secondary lymphoedema results from damage to the lymphatic system, including from cancer or cancer treatment. Sometimes lymph nodes and lymph vessels are removed or damaged during surgery or radiotherapy, which can stop the lymphatic system from working properly. This means that the lymph fluid doesn’t drain as it should and instead builds up in the tissues, causing swelling.

Because lymphoedema is easier to manage and treat in its early stages, it is important to look out for any signs you are developing lymphoedema.

Signs may begin gradually in the affected area and they may come and go. You may have one or more of the following signs;

  • Feeling of tightness, heaviness or fullness
  • aching in the affected area
  • swelling that comes and goes or is more noticeable at the end of the day
  • clothing, shoes or jewellery feel tighter than usual
  • not being able to fully move the affected limb
  • pitting on the skin (where gentle pressure leaves an indent on the skin?

Your doctor will ask you about your medical history and examine the affected area. They will assess the level of swelling and any pitting, thickening or damage to the skin. Many doctors will refer you to a trained lymphoedema practitioner for a full assessment.

See our factsheet for more information on Understanding Lymphoedema

Appetite changes

You may lose your appetite because of the effects of cancer itself, the treatment, or side effects, such as feeling sick, not enjoying the smell of food, or feeling upset. This is a common issue for people diagnosed with cancer, but it is important to keep trying to eat well so your body gets the nourishment it needs to maintain your weight.

How to manage loss of appetite:

  • Eat small meals frequently, e.g. every 2-3 hours.
  • Use a smaller plate – a big plate of food may put you off eating
  • Eat what you feel like, when you feel like it.
  • Include a variety of food in your diet as this may improve your overall intake.
  • Sip fluids throughout the day, and replace water, tea and coffee with drinks that add energy (kilojoules/calories), such as milk, milkshakes, smoothies or soup.
  • Relax dietary restrictions. During treatment, maintaining your weight or regaining weight you have lost is more important than avoiding full-fat and other high-energy or high-sugar foods.
  • Gentle physical activity can stimulate appetite.
  • Make meals as enjoyable as possible.

See our booklets and factsheets for more information on Nutrition and Cancer and Understanding Changes in Taste and Smell

Nausea and vomiting

If you are having chemotherapy, you will be given anti-nausea medicine with your treatment and to take home afterward. In many cases, this will prevent severe nausea (feeling sick) and vomiting, but some people do still feel sick and many vomit. Radiation therapy, other medicines and the cancer itself can also cause nausea and vomiting.

Nausea and vomiting can also be triggered by stress, food odours, gas in the stomach or bowel, motion sickness, or even the thought of having treatment (known as anticipatory nausea or vomiting).

How to cope with nausea and vomiting:

  • Take anti-nausea medicines as prescribed, paying special attention to the timing. Let the doctor know if the medicines don’t seem to be working, as they can offer you a different one to try.
  • Have a light snack before chemotherapy and wait a few hours before eating again.
  • Eat small meals frequently (every 2-3 hours) during the day.
  • Snack on dry or bland foods, and choose cold foods or foods at room temperature instead of hot, fried, greasy or spicy foods.
  • Eat and drink slowly, and chew your food well.
  • Try drinks and food with ginger, e.g. ginger biscuits or non-alcoholic ginger beer.
  • Avoid foods that are overly sweet, fatty, fried, spicy or oily, or that have strong smells.
  • Brush teeth regularly and rinse mouth to help reduce unpleasant tastes that may make you feel nauseated.
  • Don’t eat your favourite food when feeling nauseated, otherwise you may develop a permanent dislike.
  • Sip small amounts of fluids as often as possible. Try dry ginger ale, cold flat lemonade, soda water, Lucozade, sports drinks or chilled tomato juice.
  • Try sucking on a hard lolly, crushed ice cubes or an iceblock – this can be soothing.
  • See your doctor if you are unable to keep fluids down, or if the vomiting lasts more than 24 hours, as there is a danger that you may become dehydrated.
  • Introduce drinks slowly once the vomiting has stopped, e.g. clear cool drinks, diluted fruit drinks, Bonox/Bovril, clear broth and weak tea.
  • Start eating small amounts of plain foods once vomiting is under control.
  • Introduce milk gradually and in small amounts or have yoghurt which is more easily digested.
  • Gradually increase your food intake until your eating returns to what is normal for you. Your doctor or dietitian may advise you to take a nutritional supplement on your good days to make up for when you can’t eat properly.

See our booklets and factsheets for more information on Nutrition and Cancer and Understanding Changes in Taste and Smell

Constipation and diarrhoea

Cancer treatments may cause constipation and/or diarrhoea.

Tips for managing constipation:

  • Drink plenty of fluid, 8-10 glasses a day.
  • Eat foods high in fibre
  • Ask your doctor about using a laxative
  • Exercise every day – check with your doctor about the amount and type of exercise that is right for you
  • If you have had surgery for bowel cancer, speak to your health care team about specific dietary advice.

Tips for managing diarrhoea:

  • Drink plenty of fluids to avoid becoming dehydrated.
  • Choose low-fibre foods
  • Avoid foods that increase bowel activity
  • Try soy milk or lactose-free milk if you develop a temporary intolerance to lactose
  • Don’t eat too many raw fruit and vegetable skins and wholegrain cereals

See our booklets and factsheets for more information on Nutrition and Cancer

Sexuality and intimacy

Whether or not we have a partner, we are sexual beings – having cancer does not change that. Cancer can, however, affect your sexuality and your ability to be intimate in both physical and emotional ways.

Adapting to changes in sexuality and intimacy

  • Plan sexual activity for the time of day when your pain is lowest. If you are using pain medication, take it shortly before sex so it will have maximum effect.
  • Discuss changes in your libido with your partner so they understand how you’re feeling and don’t feel rejected.
  • Ask your doctor about having a hormonal assessment to check your hormone levels. Ask your doctor about taking tablets or having injections to help with erections.
  • To manage low mood, try to be as active as possible. Plan activities for each day such as exercise, spending time with other people, or reading.

See our booklet for more information on Sexuality, Intimacy and Cancer


Cancer and its treatment may cause fertility problems. This will depend on the type of cancer and treatment you have. Infertility can range from difficulty having a child to the inability to have a child. Infertility after treatment may be temporary, lasting months to years, or permanent.

It is best to talk about ways to preserve or protect your fertility before cancer treatment begins. It may be possible to freeze your eggs, embryos or sperm for use in the future. Fertility is something your treatment team should discuss with you, but you can also bring up the topic yourself.

If you aren’t offered the opportunity to see a fertility specialist before treatment, ask your GP or cancer specialist for a referral.

See our booklet for more information on Fertility and Cancer

Side effects by treatment type

For more information on the specific side effects of each cancer treatment please refer to the Understanding Cancer Treatment booklet series.

Some useful resources about different side effects

Fatigue and Cancer

This fact sheet will help you understand more about fatigue, a common side effect of cancer and cancer treatments. Fatigue is when you feel very tired, weak, drained or worn out

View more

Hair Loss

This factsheet provides information on hair loss that may result as a side effect of cancer treatment. Any treatment which acts on rapidly dividing cancer cells can also affect other rapidly dividing cells such as hair follicles

View more

Understanding Lymphoedema

This factsheet will help you understand more about secondary lymphoedema, a possible side effect of cancer treatments. Lymphoedema is the swelling that develops when lymph fluid builds up in the tissues under the skin or sometimes deeper in the abdomen and chest areas.

View more

Nutrition and Cancer

This booklet will help you understand more about nutrition and how to eat well before, during and after cancer treatment. We cover the guidelines for healthy eating and some of the common eating problems caused by cancer or its treatment

View more

Understanding Taste and Smell Changes

This fact sheet will help you understand more about the possible effects of cancer treatments on your experience of eating. Some treatments can change the taste and smell of your food, or the feeling of food in your mouth

View more

Sexuality, Intimacy and Cancer

This booklet will help you understand the ways cancer and its treatment may affect your sexuality, sex life and relationships

View more

Fertility and Cancer

This booklet is for people who have questions about the impact of cancer treatments on their fertility

View more

Understanding Peripheral Neuropathy

This fact sheet will help you understand more about the nerve condition known as peripheral neuropathy, which sometimes happens as a result of cancer or cancer treatment

View more

If you are a patient, family or friend and would like to order a copy of any of these resources, please call 13 11 20. If you would like to see what other resources we have available, please visit our Download Resources page