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Managing Side Effects of Radiation Therapy: Care Instructions


Radiation is often used to treat cancer. Radiation therapy uses high-energy rays or radioactive material to kill cancer cells or keep them from growing. Radiation is very good at killing cancer cells. But it can also affect normal cells. This can lead to side effects.

The most common side effects of radiation therapy are feeling very tired and having sensitive skin in the treated area. Some people lose their appetite, feel sick to their stomach (nauseated), or have other problems. It depends on the area treated. For example, treating your lungs may lead to a cough. Radiation therapy for brain cancer can cause hair loss, but the hair usually grows back.

Your doctor can give you medicine to ease some side effects. You also can do a lot at home to relieve symptoms. To feel as well as possible, get plenty of rest, drink plenty of fluids, and eat a healthy diet. Most side effects will go away within a few weeks after you finish your therapy. Some side effects last longer or may not show up until much later. And in some cases, a side effect may be permanent.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse advice line (811 in most provinces and territories) if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

How can you care for yourself at home?


  • Be safe with medicines. Take your medicines exactly as prescribed. Do not stop or change a medicine without talking to your doctor first.
  • Ask your doctor before taking any medicine, including natural health products and over-the-counter medicines.

Appetite problems and nausea

  • Try to eat a variety of healthy foods, like fruits, vegetables, whole grains, and lean protein If you don't feel like eating, drink liquid meal replacements for extra calories and protein.
  • Try to eat your main meal early.
  • Ask your doctor if you can take an over-the-counter medicine, such as dimenhydrinate (Gravol), to help with nausea.
  • If you are vomiting or have diarrhea:
    • Drink plenty of fluids to prevent dehydration. Choose water and other clear liquids. If you have kidney, heart, or liver disease and have to limit fluids, talk with your doctor before you increase the amount of fluids you drink.
    • When you are able to eat, try clear soups, mild foods, and liquids until all symptoms are gone for 12 to 48 hours. Other good choices include dry toast, crackers, cooked cereal, and gelatin dessert, such as Jell-O.

Rest and activity

  • Try to get some physical activity every day, but don't get too tired.
  • Get plenty of rest, and sleep as often as you feel the need. You may feel tired for several weeks.
  • Ask for help with daily errands and tasks.
  • Keep doing the hobbies you enjoy as your energy allows.

Managing stress

  • Consider joining a support group. Sharing your feelings with your partner, a good friend, or other people with similar problems is a good way to reduce tension and stress.
  • Practice some relaxation techniques. Methods like deep breathing, muscle relaxation, and meditation are all ways to lower your stress level.
  • Express yourself through art. Try writing, crafts, dance, or art to relieve stress. Some dance, writing, or art groups may be available just for people who have cancer.
  • Be kind to your body and mind. Getting enough sleep, eating a healthy diet, and taking time to do things you enjoy can contribute to an overall feeling of balance in your life and help reduce stress.
  • Get help if you need it. Discuss your concerns with your doctor or counsellor.

Mouth sores

  • If your mouth is sore and dry, sip cool water or suck on ice chips.
  • Eat soft, bland foods that are easy to swallow, such as applesauce, cottage cheese, soft-cooked eggs, and yogurt.
  • Avoid spicy and salty foods. And avoid coarse foods such as raw vegetables, dry crackers, and nuts.
  • If you had radiation to your mouth area, clean your mouth and teeth often, because you have a greater chance of getting cavities. Use an extra-soft toothbrush and a mild toothpaste.
  • Do not smoke. Smoking can make your symptoms worse. If you need help quitting, talk to your doctor.

Skin care

  • Use lukewarm water for showers or quick baths. Pat yourself dry with a soft towel, being careful not to rub off any ink marks that are used for your radiation.
  • Be gentle with your skin in the treatment area. Wash skin gently, using only lukewarm water.
  • Avoid putting heating pads or cold packs or anything that is hot or cold on this skin.
  • Avoid rubbing or scratching the treated area, even if it is itchy.
  • Wear soft, loose fabrics.
  • Ask your doctor which soap and lotion products you can use.
  • Always wear sunscreen on exposed skin. Make sure to use a broad-spectrum sunscreen that has a sun protection factor (SPF) of 30 or higher. Use it every day, even when it is cloudy.
  • Avoid exposing the treated area to the sun.

When should you call for help?

Call 911 anytime you think you may need emergency care. For example, call if:

  • You passed out (lost consciousness).

Call your doctor or nurse advice line now or seek immediate medical care if:

  • You have a fever.
  • You have abnormal bleeding.
  • You have new or worse pain.
  • You think you have an infection.
  • You have new symptoms, such as a cough, belly pain, vomiting, diarrhea, or a rash.

Watch closely for changes in your health, and be sure to contact your doctor or nurse advice line if:

  • You are much more tired than usual.
  • You have swollen glands in your armpits, groin, or neck.
  • You do not get better as expected.

Where can you learn more?

Go to

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Care instructions adapted under license by your healthcare professional. If you have questions about a medical condition or this instruction, always ask your healthcare professional. Healthwise, Incorporated disclaims any warranty or liability for your use of this information.