Symptoms of Radiation and How to Manage Them

Radiation therapy is an important treatment that specialists use to fight cancer. Doctors target cancer cells with high-energy beams that damage cells and stop cancer from growing. You may have radiation as your only treatment, or you may have radiation along with another cancer therapy.

Using radiation, doctors help destroy cancer and shrink tumors while minimizing damage to healthy parts of your body. But there are some radiation side effects. Here’s what you need to know about radiation therapy.

How Radiation Therapy Works

Depending on the type of cancer you have, your doctor may recommend radiation therapy. They may treat you with:

  • External beam radiation therapy: Doctors use a machine (linear accelerator) to point radiation at areas of the body that need treatment. You won’t feel any pain or discomfort during external beam radiation therapy.
  • Internal radiation therapy: Doctors put a radiation source like beads, pellets, or seeds inside your body. Known as brachytherapy, this treatment uses a high dose of radiation to destroy cancer cells in a specific area.
  • Systemic radiation: Doctors administer some systemic radiation orally (as a pill or liquid you swallow) or through injection of a radioactive substance into your veins. Radiation then travels throughout your body to treat cancer cells.

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Common Radiation Symptoms After Treatment

Cancer treatment symptoms are common in many people. If you have radiation therapy, you may experience radiation symptoms. These symptoms may last for weeks to a few months after you finish all your radiation treatments.

Not everyone will experience radiation side effects. Each person is different. But common radiation symptoms include:


After radiation therapy, you may feel extremely tired (fatigue). If you experience fatigue after treatment, get plenty of rest. Try to get some help with home and childcare duties so you can focus on taking it easy.

Skin changes

It’s common to experience changes to your skin when you’re treated with radiation. You may develop:

  • Blisters.
  • Dark, blotchy skin.
  • Dry skin.
  • Itchy skin.
  • Moist skin, especially in skin folds.
  • Peeling.
  • Redness.
  • Swelling.

Skin changes are especially common with external beam radiation because energy passes through your skin. You may not notice these changes until you’ve had a few weeks of treatment. Skin cells become damaged and new healthy cells can’t grow during frequent radiation treatments.

Your doctor may recommend that you use certain skin products and avoid others. It’s a good idea to:

  • Limit the number of baths or showers you take and keep them short.
  • Protect your skin from the sun.
  • Use gentle soaps without fragrances.
  • Keep your skin from drying out with creams or ointments your doctor recommends.
  • Wear loose clothes made from soft fabrics.

Hair loss

Hair loss is a cancer treatment symptom many people fear. Not everyone experiences hair loss after radiation treatment. Those who do typically lose hair only on the part of their body that’s treated.

Hair typically grows back about three to six months after radiation treatment ends. If you’ve had a high dose of radiation, you may notice your hair is thinner when it grows back. Sometimes, hair may not grow back at all in the treatment area.

Radiation Symptoms by Cancer Type

You may be more likely to experience certain radiation symptoms depending on cancer type. The side effects you have depend on the type of treatment you get and the area of your body where you receive treatment.

Brain fog

If you’re treated with radiation therapy for brain cancer, you may have trouble concentrating or remembering things after treatment. Use a calendar and make lists to help stay on top of things you need to do or remember.

Getting plenty of rest and some exercise may help too. Talk to your doctor about whether physical activity is right for you.

Mouth and throat problems

Treatment for head and neck cancers can impact your mouth and throat. Symptoms may include:

  • Changes in how you taste food.
  • Difficulty with swallowing.
  • Dry mouth.
  • Swollen gums.
  • Tooth decay.

Talk to your care team about how to manage these symptoms. It may help to eat moist, non-spicy foods and drink water frequently. Rinsing gently with baking soda and water, or chewing gum, may also help keep your mouth more comfortable.

Nausea, vomiting, and diarrhea

Nausea, vomiting, or diarrhea can occur when you receive radiation treatment to your:

  • Abdomen
  • Pelvis
  • Stomach
  • Rectum

Let your care team know if you can’t keep food down or if you experience symptoms of dehydration. Losing fluid through vomiting and diarrhea can cause low levels of salt and potassium.

Call your doctor if you have:

  • Dark urine or an inability to urinate.
  • Fever.
  • Dizziness.

Urinary issues

Radiation treatment to your pelvis can cause bladder and urinary tract problems. You may have burning or pain when you pee (urinate). You may feel like you can’t empty your bladder fully.

Pain and inability to urinate may be signs of radiation cystitis. This condition develops when your bladder becomes irritated after radiation treatment.

Sometimes, urinary tract infections (UTI) develop after radiation treatment. Let your doctor know if you have:

  • Bloody urine.
  • Fever.
  • Pain, especially in your back.
  • Trouble urinating.

Your doctor may prescribe medication (antibiotics) if you develop a UTI.

Sexual or fertility problems

Talk to your care team about whether radiation therapy to your pelvis might affect your ability to have children (fertility). Doctors can recommend steps to protect your fertility before treatment begins.

Radiation treatment to the pelvis can also change how you feel during sexual activity. You may experience:

  • Burning, itching, or dryness in vaginal tissue.
  • Nerve changes that make it difficult to have an erection.

Your care team can help you know what to expect after radiation treatment. They can also recommend treatments to help ease these radiation symptoms.

Easing Radiation Side Effects

When radiation symptoms or other cancer treatment symptoms affect your life, you don’t need to suffer in silence. Talk to your cancer care team about what you’re experiencing. Palliative care specialists can help with symptoms of radiation and how to manage them.

American Cancer Society, Radiation Therapy Side Effects,

American Society of Clinical Oncologists, Side Effects of Radiation Therapy,

National Cancer Institute, Radiation Therapy to Treat Cancer,

National Cancer Institute, Memory or Concentration Problems and Cancer Treatment,

National Cancer Institute, Diarrhea: Cancer Treatment Side Effect,

About UPMC Hillman Cancer Center

When you are facing cancer, you need the best care possible. UPMC Hillman Cancer Center provides world-class cancer care, from diagnosis to treatment, to help you in your cancer battle. We are the only comprehensive cancer center in our region, as designated by the National Cancer Institute. We have more than 70 locations throughout Pennsylvania, Ohio, and New York, with more than 200 oncologists – making it easier for you to find world-class care close to home. Our internationally renowned research team is striving to find new advances in prevention, detection, and treatment. Most of all, we are here for you. Our patient-first approach aims to provide you and your loved ones the care and support you need. To find a provider near you, visit our website.