Side effects of chemotherapy for rectal cancer
Chemotherapy can cause side effects. These can usually be well controlled with medicines.
We’ve described some of the more common ones here and ways of reducing them. They will gradually disappear once your treatment is over.
Chemotherapy can reduce the number of white blood cells, which help fight infection. If the number of your white blood cells is low, you’ll be more prone to infections. A low white blood cell count is called neutropenia.
Always contact the hospital immediately on the 24-hour contact number you’ve been given and speak to a nurse or doctor if:
you develop a high temperature – this may be over 37.5°C (99.5°F) or over 38°C (100.4°F) depending on the hospital’s policy – follow the advice that you have been given by your chemotherapy team
you suddenly feel unwell, even with a normal temperature
you feel shivery and shaky
you have any symptoms of an infection such as a cold, a sore throat, a cough, passing urine frequently (urine infection) or diarrhoea.
If necessary, you’ll be given antibiotics to treat any infection. You’ll have a blood test before each cycle of chemotherapy to make sure your white blood cells have recovered. Occasionally, your treatment may need to be delayed if the number of your white blood cells is still low.
Chemotherapy can also reduce the number of platelets in your blood. These cells help blood to clot. Tell your doctor if you have any bruising or bleeding you can’t explain. This includes nosebleeds, bleeding gums, blood spots or rashes on the skin.
Anaemia (reduced number of red blood cells)
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If chemotherapy reduces the number of red blood cells in your blood, you may become very tired and feel you have no energy. You may also become breathless and feel dizzy and light-headed. These symptoms happen because the red blood cells contain haemoglobin, which carries oxygen around the body.
If your haemoglobin is low, you may be offered a blood transfusion. You’ll feel more energetic and any breathlessness will be eased.
Some chemotherapy drugs can cause diarrhoea. This can start a day or several days after the treatment.
If you’re taking chemotherapy tablets or capsules at home, tell your doctor or nurse if you have diarrhoea. Your treatment may need to be stopped until the diarrhoea is better.
Drink plenty of fluids if you have diarrhoea. It may also help to eat a low-fibre diet. If you have a stoma, your stoma care nurse can give you advice and support.
Some people need to make sure they are close to a toilet throughout their treatment and for a while afterwards. This can be frustrating, but it usually improves gradually a few weeks after treatment has ended. If the diarrhoea continues, it’s important to talk to your cancer specialist or stoma nurse. They can help you find ways of managing it.
Your doctor can prescribe anti-sickness drugs to prevent, or greatly reduce, nausea or vomiting. If the sickness isn’t controlled, or if it continues, tell your doctor – they can prescribe other anti-sickness drugs that may work better for you.
Your mouth may become sore or dry, or you may develop ulcers during treatment. Drink plenty of fluids, and clean your teeth regularly with a soft toothbrush, to help reduce the risk of infections in your mouth. Tell your nurse or doctor if your mouth is sore. They can prescribe mouthwashes and medicine to prevent or clear mouth infections.
We have more information about mouthcare.
You’re likely to become tired and have to take things slowly. Try to pace yourself and save your energy for things that you want to do or that need doing. Balance rest with some physical activity – even going for short walks will help increase your energy levels.
The drug oxaliplatin can sometimes cause a spasm (tightening) in the voice box (larynx). This may happen during treatment or within the few hours after it. It can temporarily affect breathing and swallowing but will settle on its own. Cold temperatures may cause the spasm. Avoid cold drinks, ice cream or ice cubes during and for a few days after treatment. In cold weather, wrap up warmly and cover your nose and mouth when going out.
Most drugs used to treat bowel cancer do not cause total hair loss, but your hair may thin. Hair grows back once the treatment has finished. Your nurse can give you advice about coping with hair loss.
This is sometimes called palmar-plantar, or hand-foot, syndrome. It can be caused by capecitabine or 5FU and will improve when the treatment is finished. Using non-perfumed moisturising creams can help to relieve symptoms. Your doctor can prescribe creams if necessary.
Changes in the way the heart works
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Fluorouracil (5FU) and capecitabine can affect the way the heart works. If you are having one of these drugs, you may have tests to see how well your heart is working. You may have these before, during and sometimes after treatment.
If you have pain or tightness in your chest, feel breathless or notice changes to your heartbeat at any time, tell a doctor straightaway. These symptoms can be caused by other conditions but it’s important to get them checked by a doctor.
Numbness or tingling in the hands or feet
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Oxaliplatin can cause this. You may also notice that you have difficulty doing up buttons or similar fiddly tasks. This is called peripheral neuropathy. It is due to effects of the drug on nerve endings.
These symptoms may be triggered by cold temperatures. If you notice that your symptoms are related to the cold, avoid cold drinks and wrap up warmly in the cold weather.
It is important to tell your doctor about any symptoms you have, as they may be helped by slightly lowering the dose of the drug.
Numbness and tingling can last for several months. In some people, it may be permanent.
It’s not advisable to become pregnant or father a child while having chemotherapy, as it may harm the developing baby. It’s important to use effective contraception during your treatment and for at least a few months afterwards. You can discuss this with your doctor or nurse.
Protecting your partner
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It’s not known whether chemotherapy drugs can be present in semen or vaginal fluids. To protect your partner, it’s safest to use a condom if you have sex within 48 hours after chemotherapy.