Radiation therapy is a proven effective cancer treatment, and one that is improving all the time, but there are some radiation therapy side effects that patients might experience.

Radiation therapy directs high-energy particles or waves, such as X-rays, gamma rays, or electron beams, at a tumor. These beams damage the DNA molecules inside cancer cells so they can no longer grow and divide. This type of treatment can cause side effects because while the radiation kills cancer cells, it may also harm nearby healthy cells.

Radiation therapy side effects are caused by healthy cells or organs being exposed to radiation in addition to the cancer cells. At Rocky Mountain Cancer Centers, we use the most advanced, state-of-the-art radiation therapy machines, including image-guided radiation therapy (IGRT), that helps reduce any exposure to non-cancerous cells, organs, and tissue. In addition, we employ various techniques proven through research to help reduce exposure, such as having you breathe in specific ways or lie in certain positions to move organs away from the radiation site.

As with any medical treatment, radiation side effects vary from patient to patient with some experiencing highly unpleasant symptoms and others barely having any at all.

The good news is that radiation therapy is becoming more precisely targeted, reducing the damage to healthy cells.

Common Side Effects of Radiation Therapy

As with any medical treatment, radiation may cause side effects in some people, but not others. Likewise, those side effects can vary. In some people, they may seem very unpleasant, while others will barely notice them. Fatigue and skin reactions are the most common radiation side effects.

Cancer Treatment-Related Fatigue

The most common side effect of any type of cancer treatment, including radiation, is fatigue, or feeling extremely tired or worn out. The majority of patients undergoing cancer treatment will experience fatigue to some degree, and it’s different than the fatigue people feel when they are healthy. Cancer-related fatigue tends to be worse and might not be alleviated with rest. It can come on slowly throughout treatment or all at once and may be exacerbated by other side effects, such as anemia and pain. Treatment-related fatigue typically resolves in the weeks after treatment has ended.

Because radiation is localized to the area of the tumor, most other side effects occur at the radiation site. That means, unless you’re getting radiation directed to your head, you probably won’t lose your hair.

Common Side-Effects

Specific radiation therapy side effects vary depending on where you receive radiation, and most will go away when treatment is completed. Some of the more common radiation side effects include:

  • Radiotherapy skin reactions. During treatment, your skin around the area receiving radiation may become red or swollen. After a few weeks, the skin may become dry, itchy, or flaky.
  • Radiation recall. Rarely, when a patient has certain types of chemotherapy along with or soon after radiation, a rash that resembles a severe sunburn may develop at the radiation site.
  • Constipation
  • Hot Flashes
  • Mouth sores, difficulty swallowing, frequent

Radiation Site-specific Side Effects

You may experience radiation therapy side effects that are specific to the type of treatment you are receiving based on the type of cancer you have.

  • Head and neck: Nausea, headaches, difficulty swallowing, mouth sores or swelling
  • Chest: Difficulty swallowing, shortness of breath, breast or nipple soreness, shoulder stiffness
  • Stomach and abdomen: Nausea and vomiting, diarrhea
  • Pelvic area: Diarrhea, rectal bleeding, incontinence, or bladder irritation

In addition, men and women may experience different side effects such as sexual dysfunction in men or disruptions in the menstrual cycle in women. Women should not become pregnant during radiation treatment because it may harm the unborn child.

Coping with Common Side Effects of Radiation

There are ways to help you ease your discomfort.

  • Get plenty of rest.
  • Eat healthily. Depending on the part of your body getting radiation, your care team may suggest changes in your diet.
  • Tell your care team about all the medicines you’re taking. Be sure to include aspirin, vitamins, or herbs and things you take only as needed, such as sleep aids, antacids, headache remedies, and antihistamines

Radiation Therapy Skin Irritation

To care for your skin in the treatment area:

  • Don’t wear elastic, or clothing that is tight or made of rough fabric.
  • Don’t rub or scratch the treated area.
  • Don’t put heat or cold — such as a heating pad or ice pack — on the treatment area without talking to your care team first. Even hot water may hurt, so showering in lukewarm water may be best.
  • Do cover the treated area when you’re outside. Ask your cancer care team about using sunscreen, and if they advise it, use a broad-spectrum sunscreen with a sun protection factor (SPF) of at least 50, and re-apply it often. Continue to protect your skin from sunlight, even after your treatment ends.
  • Don’t shave the treated area until you’ve checked with your cancer care team.
  • Do ask your cancer care team before using anything — including lotions, powders, perfumes, and deodorant — on your skin in the treatment area. 

Many skin products can leave a coating on the skin that can cause irritation, and some may even affect the dose of radiation that enters the body. There are special medical product for radiotherapy skin side effects such as Immufen cream or very effective Immufen skin gel, to keep the skin well moisturised before starting chemotherapy and throughout treatment.

Worsening Side Effects

If you are a patient and are experiencing worsening symptoms from your treatment, such as those listed below, our medical professionals are available 24 hours a day, 7 days a week to help. We can assess signs and symptoms, schedule you for an in-office, same or next day appointment and help you avoid a trip to Urgent Care, ER or unplanned hospitalization. In the event of a life-threatening emergency, always call 911. Call us if you are experiencing:

  • Chills or fever greater than 100.4
  • Burning with urination, frequency, urgency, lower back pain (UTI)
  • Productive cough with green, yellow, red, brown sputum
  • Unmanaged diarrhea, constipation, nausea, vomiting
  • Unmanaged pain
  • Swelling, redness and pain on extremities
  • Shortness of breath/chest pain
  • Dizziness with changing position or lightheadedness
  • Dark urine, less urine than normal, thirst, dry mouth (dehydration)
  • Mouth sores, difficulty swallowing, frequent or severe heartburn
  • Severe fatigue