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.

On this page you will find details about the following common side effects:

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

Fatigue

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.

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.

When hair loss does occur, it usually starts 2–3 weeks after the first treatment. Before and while your hair is falling out, your scalp may feel hot, itchy, tender or tingly. Some people find that the skin on their head is extra sensitive and they may develop pimples on the scalp. Although losing head hair is most common, you may also lose hair from your eyebrows, eyelashes, arms, legs, chest and pubic region.

Many people find losing their hair very difficult. You may feel your hair is part of your overall image and its loss can make you feel physically unattractive, vulnerable or sad. It’s natural to feel this way. Talking to your medical team may be helpful.

Tips for managing hair loss:

  • Keep your hair and scalp very clean.
  • Use a mild shampoo like baby shampoo.
  • If you want to use lotion on your head, use sorbolene. Check with your nurse before using any other hair or skin care products.
  • Wear a light cotton turban or beanie to bed if you are cold at night, or to collect hair.
  • Use a cotton, polyester or satin pillowcase as nylon can irritate your scalp. If you prefer to leave your head bare, protect it against sunburn and the cold.
  • Wear a wig, hat, scarf or turban, or go bareheaded, whatever feels best to you.

Cancer Council offers a Wig and Turban service for all cancer patients free of charge. Submit an enquiry online or phone 13 11 20 to find out more.

For more information, read our hair loss fact sheet.

Lymphoedema

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.

For more information on lymphoedema, please refer to the Understanding Lymphoedema factsheet

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.

For more information on appetite changes, please refer to the Nutrition and Cancer booklet.

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.

For more information on managing nausea and vomiting, please refer to the Nutrition and Cancer booklet.

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

For more information on managing bowel changes, please refer to the Nutrition and Cancer booklet.

Sexuality, intimacy and fertility

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.

Some cancer treatment can cause infertility. If fertility is important to you, talk to doctor about ways to preserve or protect your fertility before cancer treatment begins. It may be possible to store your sperm or eggs for use in the future.

Adapting to changes to sexuality, intimacy and fertility:

  • 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.

For more information view our Sexuality, Intimacy and Cancer or Fertility and Cancer booklet.