Possible side effects of radiotherapy

If you’re having radiotherapy, it’s possible that you will have some side effects.

Some side effects will be specific to the area of the body that is being treated. And some (like tiredness) are more general. Side effects can be mild or more troublesome depending on the strength of the radiotherapy dose and the length of treatment. Ask your doctor to explain the potential side effects before you have treatment. Lung cancer radiotherapy can cause:

  • problems with swallowing
  • tiredness
  • skin reactions
  • hair loss
  • flu-like symptoms.

If you need help and advice about dealing with certain side effects, speak to your doctor, nurse or radiotherapy staff.

Side effects of radiotherapy to the chest

You may develop side effects over the course of your treatment. These usually disappear gradually over a few weeks or months after treatment finishes. Your doctor, nurse or radiographer will discuss this with you so you know what to expect. Let them know about any side effects you have during or after treatment, as there are often things that can be done to help.

It’s not unusual to feel worse before you start to feel better. Some people can find this a very difficult time and they may feel low or even depressed for a while. The clinical oncologist can advise you about what to expect.

Problems with swallowing

After 2–3 weeks you may have difficulty swallowing, heartburn or indigestion. This is because radiotherapy can cause inflammation in the gullet (oesophagus).

These side effects can be uncomfortable but your doctor can prescribe medicines to reduce them. If you don’t feel like eating, or have problems with swallowing, you can replace meals with nutritious, high-calorie drinks. You can get these from most chemists and some can be prescribed by your GP.

We have information on eating problems and a building up diet which may help.

Tiredness (fatigue)

Not everyone feels tired during radiotherapy treatment but many people do.

Tiredness can continue for weeks to months after your treatment has finished. It can often be made worse by having to travel to hospital each day, or by other treatments such as surgery or chemotherapy.

Some people are able to continue with their day-to-day activities, but others may find they need to rest more.

Managing tiredness

Get plenty of rest but balance this with some gentle exercise, such as short walks. This will give you more energy and help to keep your muscles working. Save some energy for doing the things you enjoy. You can also ask others for help doing chores if these are tiring you out.

We have more information about coping with tiredness (fatigue).

Skin reactions

You may develop a skin reaction while having external radiotherapy. If this happens, it usually begins after about 10 days.

How your skin reacts will vary depending on the amount of radiotherapy you have. Some people may find that the skin in the treatment area becomes red and sore or itchy. Or, it may become darker with a blue or black tinge. Sometimes the skin will get very sore and it may break and leak fluid, although this doesn’t happen very often. If your skin gets very sore, your treatment may have to be delayed for a short time to allow the area to recover, although this is very rare.

If you have a skin reaction, it will usually settle down 2–4 weeks after your treatment has finished. But the area may stay slightly darker than the surrounding skin.

Managing skin reactions

During your treatment, you will usually be advised to:

  • wear loose-fitting clothes made from natural fibres, such as a cotton T-shirt
  • wash your skin gently with soap, or aqueous cream, and water and gently pat it dry (aqueous cream should not be used as a moisturiser)
  • avoid rubbing the skin
  • avoid heating and cooling pads
  • avoid shaving, if possible
  • not use hair-removing creams or products, including wax
  • use a moisturiser that is sodium lauryl sulphate-free (your radiographer can give you more information about this)
  • use normal deodorant, unless your skin is broken
  • avoid the sun and use a high sun protection factor (SPF) sunscreen (your radiographer can give you more information about this).

If you develop a skin reaction such as soreness or a change in skin colour, let the radiotherapy staff know as soon as possible. They will advise you on the best way to manage it.

After your treatment has finished, you’ll need to protect the skin in the treated area from strong sunshine for at least a year.

Once any skin reaction has settled down, you should use a suncream with a high SPF of at least 30.

You should also wear close-weave clothing and a wide-brimmed hat if your head and neck area has been treated. It’s important to remember that you can burn through clothing if you’re out in hot sun for a long time. Your radiographer can give you more information about this.

You can usually go swimming once any skin reaction has settled down. This is usually within a month of finishing treatment. Remember to use a waterproof suncream if you’re swimming outdoors.

Hair loss

This will only happen within the treatment area, so it’ll include chest hair for men or head hair if you are given prophylactic cranial radiotherapy. The hair usually grows back, although sometimes hair loss is permanent.

Late effects of radiotherapy for lung cancer

Sometimes radiotherapy for lung cancer may cause long-term side effects. These are side effects that begin during treatment but don’t go away, or side effects that develop months or years later.

The lungs may become inflamed or the tissue can become scarred (fibrosis). Let your cancer doctor or specialist nurse know if you have a cough or are short of breath.

Sometimes the gullet can become narrower, causing difficulty in swallowing. In some people, the bones in the chest area may become thinner and this may cause pain in that area.

Most people won’t get late effects. But if you notice any symptoms, always tell your cancer doctor or nurse.

Back to Radiotherapy explained

What is radiotherapy?

Radiotherapy uses high-energy rays to destroy cancer cells. This treatment aims to treat cancer or relieve symptoms.

Possible long-term effects

Side effects of radiotherapy for lung cancer can happen many months or years after treatment. These are known as long-term effects.

Who might I meet?

You will meet many different specialists before, during and after radiotherapy treatment.