Radiotherapy side effects
Radiotherapy targets cancer by using radiation (usually x-rays) on the area that needs treatment. This damages the DNA in the cancer cells. Healthy cells in the area are also damaged but they are better at recovering.

Depending on where your treatment is needed, radiotherapy can affect your body in different ways. Your doctor will be able to let you know more about your specific treatment but here are a few common side effects and what you can do to make them easier to deal with.
Tiredness Show/Hide

The damage to your healthy cells can leave you feeling tired or weak while your body repairs them. You red blood cells can also be affected which makes it harder for your body to transport oxygen to your muscles.
  • Rest and take breaks - Set aside regular times during your day when you can pause and catch your breath. You might be tempted to keep going but pushing yourself too hard will wear you down over time and leave you feeling worse later.
  • Get plenty of sleep - This seems simple but some anti-sickness drugs can upset your sleep patterns. You might need to put more planning into your bedtime routine than you normally do. Take some time to wind down at the end of the day, avoid drinking tea or coffee in the afternoon, and give yourself a regular bedtime. Keeping a routine is one of the best ways to make sure you get enough sleep every day.
  • Exercise lightly - You might not feel like it but gentle exercise will build your stamina and make you less tired in the long run. Just be sure to take it easy.
If you are constantly feeling exhausted, it could be a sign of anaemia. Talk to your doctor as they may prescribe something to treat it.

Feeling sick Show/Hide

Radiotherapy treatment can damage the soft tissue in your digestive system. This often leads to mucositis as well as feeling ill, vomiting and diarrhoea.

Your doctor might prescribe some anti-sickness medication but there are some things that you can do to make things easier.
  • Avoid fatty foods, spicy foods and acidic drinks
  • Get someone else to prepare/cook your food if the smell bothers you
  • Eat small meals several times through the day
  • Keep taking your anti-sickness medication, even if you don't feel ill
Tell a doctor if your sickness becomes severe or if you get flu-like symptoms, such as headaches, aching joints and a high temperature.

Flu symptoms usually settle within a couple of days. Just make sure to rest and drink plenty of fluids.

Problems eating Show/Hide

As well as sickness, you may find eating and drinking difficult. This can be especially true if your treatment is around your head and neck. The lining of your mouth is sensitive to radiation and can be left sore by treatment. Oral sores usually last during treatment until a few weeks after.

It's important to deal with mouth sores and any cuts early as a weakened immune system can leave you vulnerable to infection.
  • Use an alcohol free mouth wash
  • Sip drinks regularly
  • Eat soft or moist foods
  • Chew gum to increase saliva
  • Use a soft tooth brush
  • Treat any cuts or sores straight away
Skin reactions Show/Hide

Your skin may get redder or darker during treatment. It might also become dry and itchy.
  • Avoid using chemicals on your skin
  • Avoid perfumed soaps
  • Avoid shaving
  • Try using baby products like soap and shampoo as this is often milder
  • Wear loose fitting clothes during treatment
Hair loss Show/Hide

Patients usually lose hair around the treatment area and will usually grow back within a few weeks of treatment.
  • Think about cutting your hair before starting treatment
  • Don't colour your hair or use harsh chemicals
  • Wash your hair with baby shampoo
  • Brush with a soft comb
This animation shows how Gelclair can help to relieve the pain of oral lesions and ulcers caused by oral mucositis.
Apply for a free sample of Gelclair, which helps to relieve the pain oforal mucositis, a painful inflammation and ulceration of the lining of the mouth and throat.
Tell friends about Gelclair which helps to relieve the pain of oral lesions and ulcers from oral mucositis.
Healthcare Professionals click here for more information on Gelclair and oral mucositis
Healthcare Professionals click here for more information on Gelclair and oral mucositis
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