Common side effects of treatment

The type of side effects and their severity varies from person to person, depending on the type of treatment used and how an individual responds to it. There is no doubt that side effects can be very unpleasant at times, but it’s good to remember that most of them are temporary and reversible. It is important that you report any side-effects you are experiencing to your nurse or doctor because many of them can be treated successfully, reducing any unnecessary discomfort for you. It is important that you contact your doctor or the hospital for advice immediately (at any time of the day or night) if you are feeling very unwell.

Side effects of chemotherapy

Chemotherapy kills cells that multiply quickly, such as cancer cells. It also causes damage to fast-growing normal cells, including hair follicles, and cells that make up the tissues in your mouth, gut and bone marrow. The side effects of chemotherapy occur as a result of this damage. Chemotherapy in tablet form is tolerated well by most people and side effects tend to be few and mild. Intravenous chemotherapy can have more side effects, the type and severity of which will vary from one person to another, depending on what chemotherapy is used and how an individual responds to it.

Side effects of radiation therapy

Radiation therapy is always carefully planned so that it avoids as much healthy tissue as possible. However, there will always be some healthy tissue that is affected by the treatment and this will cause side effects. Side effects of radiation therapy vary depending on how much treatment you have and the area being treated. Your treatment team will discuss with you what side effects you might expect and how to manage them appropriately.

Side effects of corticosteroids

The types of side effects seen with corticosteroids depend largely on how long they are used for, and the dose given. If you are using them for a short time you may notice that your appetite increases or you may feel more restless than usual. Some people find it more difficult to get to sleep at night and sleeping tablets or other natural therapies are sometimes recommended.

Sometimes corticosteroids can affect your mood and concentration as well. Corticosteroids can cause a rise in the blood sugar. Diabetics may find they need more of their diabetes medication while they are taking these drugs and some people who are not normally diabetic may require treatment to keep their blood sugar at acceptable levels. It is important to keep a check on the blood sugar and keep a diary of the levels and the amount of diabetic medication being taken. Diabetics will already know how to do this. People whose blood sugar only goes up when they are on corticosteroids may be given information on diet and taught how to measure their blood sugar and adjust their medication. Blood sugar levels usually return to normal once the steroids are finished.

Many of the side effects of corticosteroids are temporary and should pass once you finish taking them. Long-term use of corticosteroids may cause some other effects such as fluid retention and an increased susceptibility to infections. Aching joints such as the knees and hips have also been reported.

Effects on the bone marrow

Treatment for a blood condition will affect your bone marrow’s ability to produce normal blood cells. As a result, your blood count (the number of blood cells circulating in your blood) will generally fall within a week of treatment, increasing the risk of infection and bleeding.

Platelets – Your platelet count may also be affected by your disease and by the chemotherapy you are receiving and you may become thrombocytopenic (a reduction in the number of platelets circulating in the blood). When your platelet count is very low you can bruise and bleed more easily. During this time it is helpful to avoid sharp objects in your mouth such as toothpicks, as these can cut your gums. Using a soft toothbrush also helps to protect your gums.

Common bleeding problems include gums, nose and in women prolonged menstruation. If the level drops too low or you are experiencing bleeding you will be given an infusion of platelets. Sometimes other medications or minor procedures will be required to stop any bleeding. Do not take aspirin or ibuprofen in any form as this can increase the risk of bleeding if your platelets are low.

Red cells – If your red blood cell count and haemoglobin levels drop you will probably become anaemic. When you are anaemic you feel more tired and lethargic than usual. If your haemoglobin level is very low, your doctor may prescribe a blood transfusion.

The point at which your white blood cell count is at its lowest is called the nadir. This is usually expected 10 to 14 days after having your chemotherapy. During this time you will be at a higher risk of developing an infection. At this stage you will also be neutropenic, which means that your neutrophil count is low. Neutrophils are important white blood cells that help us to fight infection.

White cells – The point at which your white blood cell count is at its lowest is called the nadir. This is usually expected 10 to 14 days after having your chemotherapy. During this time you will be at a higher risk of developing an infection. At this stage you will also be neutropenic, which means that your neutrophil count is low. Neutrophils are important white blood cells that help us to fight infection.

Sometimes your doctor may decide to use a growth factor such as G-CSF to help the recovery of the bone marrow. This drug works by stimulating the bone marrow to increase the production of neutrophils. G-CSF is given as an injection under the skin (subcutaneous). This is quite a simple procedure and the nurse will teach you or a family member (or friend) to do this at home. Major side effects are uncommon, but occasionally aching bones may occur.


Most people experience some degree of tiredness in the days and weeks following treatment. Having plenty of rest and a little light exercise each day may help to make you feel better during this time. Getting out into the fresh air and doing some gentle exercise is important for your general feeling of wellbeing and it also may help to reduce your fatigue. It is also important to listen to your body and rest when you are tired. Fatigue is a common side effect of treatments and a symptom of cancer itself.

Nausea and vomiting

Nausea and vomiting are often associated with chemotherapy and some forms of radiation therapy. These days however, thanks to significant improvements in anti-sickness (anti-emetic) drugs, nausea and vomiting are generally very well controlled. You will be given anti-sickness drugs before your treatment, and for a few days after your treatment has finished. Be sure to tell the nurses and doctors if the anti-emetics are not working for you and you still feel sick. There are many different types of anti-emetics that can be tried. A mild sedative may also be used to help stop you feeling sick. This will help you to relax but it might make you a little sleepy. Be sure to tell the nurse if you have a history of travel sickness or nausea and vomiting with pregnancy as more medication may be required.

Some people find that eating smaller meals more frequently during the day, rather than a few large meals, helps to reduce nausea and vomiting. Many find that eating cool or cold food is more palatable, for example jelly or custard. Drinking ginger ale or soda water and eating dry toast may also help if you are feeling sick. Getting plenty of fresh air, avoiding strong or offensive smells, and taking the prescribed anti-sickness drugs as recommended by the nurse and doctor should also help.

Changes in taste and smell

Both chemotherapy and radiation therapy can cause changes to your sense of taste and smell. This is usually temporary but in some cases it lasts up to several months. During this time you may not be able to enjoy the foods and drinks that you used to love and this can be very disappointing, but it will pass. Some people find that adding a little more sugar to sweet foods and salt to savoury foods can help.

Mucositis (sore mouth)

Mucositis is an inflammation of the lining of the mouth, throat or gut and is a common and uncomfortable side effect of chemotherapy, and some forms of radiation therapy. It usually starts about a week after the treatment has finished and goes away once your blood count recovers. During this time your mouth and throat could get quite sore. Soluble paracetamol and other topical drugs (ones which can be applied to the sore area) can help. If the pain becomes more severe, stronger pain killers might be needed. Having ice chips or an ice block to suck on can be other ways of relieving the discomfort caused by mucositis. Ask your doctor or nurse for help if mucositis is a problem for you.

It is important to keep your mouth as clean as possible while you are having treatment to help prevent infection. It is particularly important to attend to mouth care regularly while your mouth is sore. Your nurse will show you how to care for your mouth during this time. This may include using a soft toothbrush and mild toothpaste. Avoid commercial mouthwashes, like the ones you can buy at the supermarket as these are often too strong, or they may contain alcohol which will hurt your mouth. Your doctor will supply an appropriate gentle mouth wash. Keep your lips moist with a lip balm or chapstick to avoid cracking.

Occasionally mouth pain or mouth ulcers may develop as a result of infection e.g. thrush (candida albicans), cold sores (Herpes simplex). These need specific treatment which will be prescribed by your doctor.

Bowel changes

Chemotherapy and radiation therapy can cause damage to the lining of your bowel wall. This can lead to cramping, wind, abdominal swelling and diarrhoea. Be sure to tell the nurses and doctors if you experience any of these symptoms. If you develop diarrhoea, a specimen will be required from you to ensure that the diarrhoea is not the result of an infection. After this you will be given some medication to help stop the diarrhoea and/or the discomfort you may be feeling.

It is also important to tell the nurse or doctor if you are constipated or if you are feeling any discomfort or tenderness around your anus when you are trying to move your bowels as haemorrhoids can be a problem. You may need a gentle laxative to help soften your bowel motion.

Hair loss

For most of us, the thought of losing our hair is very frightening. Hair loss is unfortunately a very common side effect of chemotherapy and some forms of radiation therapy. It is, however, usually only temporary. The hair starts to fall out within a couple of weeks of treatment and tends to grow back three to six months later. In the meantime there are lots of things that you can do to make yourself feel more comfortable. Hair loss will affect all bodily hair but in varying degrees from thinning out to complete loss.

Avoiding the use of heat or chemicals and only using a soft hair-brush and a mild baby shampoo can help reduce the itchiness and scalp tenderness which can occur while you are losing your hair. When drying your hair, pat it gently rather than rubbing it with a towel. Some people find it more comfortable to simply have a short hair cut when they notice their hair starting to fall out.

You need to avoid direct sunlight on your exposed head (by wearing a hat or similar head covering) because chemotherapy (and radiation therapy) makes your skin even more vulnerable to the damaging effects of the sun (i.e. sunburn and increased risk of developing skin cancers). Remember that without your hair, your head can get quite cold, so a beanie might be useful, especially if you are in an air-conditioned environment like a hospital. Hair can also be lost from your eyebrows, eyelashes, arms, legs and pubic area.

Skin reactions

Chemotherapy can make your skin dry and sensitive while radiation therapy can cause a reddening of the skin which may also flake and become itchy. Using moisturisers regularly can help. While you are having radiation therapy you should avoid any creams or moisturisers that contain traces of metals. Gentle washing (avoiding perfumed products like scented soaps) and drying (patting rather than rubbing) is often recommended if having radiation therapy. Chemotherapy and radiation therapy makes your skin more vulnerable to the damaging effects of the sun (i.e. sunburn and increased risk of developing skin cancers), so regular sun protection is recommended.