Radiotherapy Side Effects

What type of side effects will the patient experience?

The side effects will depend on the type of radiotherapy treatment, the part of the body that is being treated and how much treatment is received. The therapy radiographers who operate the radiotherapy machines are highly skilled professionals trained to give information, support and advice on how to manage side effects. Everyone reacts differently to treatment – and therefore side effects vary from person to person, however most are temporary and rarely severe.  Some patients experience the effects of treatment early on, many will not feel any effects until it has finished.

Before a consent form is signed, the doctor will discuss any possible temporary or permanent side effects so that a patient can make an informed decision, but to give you some idea, these are the main ones to look out for.

Tiredness – Radiotherapy can make a patient feel more tired than usual. If possible they can continue normal activities but they should always listen to their body and rest if needed. There is plenty of advice you can look at on ways to save energy and cope with everyday activities. This website has some good information –

Nausea and vomiting – Depending on which part of the body is being treated, some people feel sick during radiotherapy. This will usually cease after a day or two but if it is persistent, a doctor can prescribe drugs to control it (without having to suspend the radiotherapy treatment)

Eating and drinking – It is important that patients eat well and drink plenty of fluids every day (about 2 litres). A dietician or nutritionist can help plan meals and ensure that the right foods are eaten to maintain good health whilst undergoing treatment.

Hair loss – Radiotherapy can cause hair loss but only in the area being treated. Most will be temporary and will grow back within 2-3 months of treatment finishing.

Sore skin – During treatment the skin can become red and sore and it is important that it is not irritated. Shaving, deodorants, perfumes or lotions should be avoided unless they have been recommended by the team caring for the patient. Protection from sun and extreme temperatures is also important. The affected area can be washed gently using a mild unperfumed soap (e.g. baby soap) and patted dry. If a skin reaction is observed, a doctor may prescribe or suggest a suitable cream or lotion.

N.B. There has been little research into the effects of radiotherapy on different ethnic skin types. However, anecdotal evidence suggests that people with darker skin may develop greater skin reactions during treatment than people with lighter skin.

Clothing – It is recommended that loose, casual clothing made from natural fibres should be worn during treatment. Depending on the type of treatment, there may be ink marks on the skin which may rub off onto clothes. These stains can be removed using a biological washing powder, but it may be advisable to wear clothing that doesn’t matter too much during treatment.

Joint or muscle stiffness – Occasionally stiffness to joints or muscles can occur at any time up to two years after treatment has finished. Regular exercise to these joints and muscles can prevent stiffness.

Late side effects – Some side effects can develop much later on and these are called ‘long term’. For some people these can be permanent. This will depend on the part of the body that has been treated, the dose of radiotherapy received and other factors such as why radiotherapy was used in the first instance. The doctor will be able to explain these side effects and also the likelihood of them occurring.

During the course of radiotherapy, patients may require regular blood tests to monitor general health. Radiotherapy has been known along with other cancer therapies to cause blood levels to drop meaning it may be necessary for a blood transfusion. All patients are closely monitored by the specialist team of doctors, nurses and radiographers.