Side-Effects of Radiation Therapy for Cancer Treatment

Radiation Therapy Side-Effects For Cancer Treatment

Radiation therapy for cancer, administered by a radiation oncologist, radiation physicist, or another trained medical professional, is a type of cancer treatment where high-energy waves are used to target cancer cells. These may be gamma rays, X-rays, protons, or electron beams. Radiation therapy targets fast-growing cancer cells and cleaves their DNA to destroy and kill them. Although some normal cells are affected after radiation, they usually proliferate when the therapy stops.

Radiation therapy is different from chemotherapy and other similar treatments in that it exposes the body to radiation locally. In chemotherapy, the whole body is exposed to drugs. In some cases, radiation may affect the whole body when the radioactive substance is injected in a vein or administered through the mouth to localize in the region of the tumor.

Radiation Therapy Administration and Side Effects

Radiation therapy for cancer is administered in about 50% of the cases. It may or may not involve the use of other treatments depending on the stage and type of cancer. Radiation is generally helpful as far as the cancer is located in a specific region and has not become systemic. It may also be useful when cancer recurs or reaches a more advanced stage.

Three types of radiation therapy are administered depending on the cancer type:

  • External administration by directing the waves to the tumor over several weeks such as in the case of radiation therapy for breast cancer or colon cancer
  • Internal administration by placing a radioactive source inside the body (brachytherapy) such as in the uterus, prostate, head, or neck
  • Systemic therapy using radioactive drugs administered through the vein or mouth

Early-stage cancer is a good candidate for radiation therapy. When administered at the right time, it may cause the tumor to shrink and resolve. Sometimes, your doctor may prescribe the use of anti-cancer drugs. In other cases, radiation may be used before surgery to prevent cancer recurrence after surgery. When radiation is applied to a localized occurrence of cancer, it may prove to be less damaging when compared to other therapies. Radiation may also be combined with drugs known as radiosensitizers that make cancer cells more sensitive to radiation.

Radiation therapy comes with side effects, but their nature and extent depend on the degree of radiation you receive, the type of therapy, and the part of your body which was affected by cancer. When radiation is combined with drugs, the side effects of chemotherapy and radiation may be worse. The outcome and side effects also depend on your overall health status.

Radiation may have mild to severe side effects depending on your specific case. An individual may experience either early or late side effects. Fatigue, skin problems, hair loss (in some cases),  and nausea are the early side effects and start immediately after the treatment is initiated. The early side effects may last several weeks even after the treatment ends, gradually improving over time.

Handling Common Early Side Effects of Radiation

Common early side effects of radiation therapy include skin damage, fatigue, mouth problems, stomach problems, hair fall, and fertility issues.


Fatigue is a common radiation therapy side effect and bothers most individuals as it can last for a long time without improvement even after resting. It prevents an individual from engaging in healthy work and family life. Sometimes, a person may experience heart and lung problems, which may persist for years. It may take a few weeks for the fatigue to go away after radiation therapy.

Skin Conditions

A person may experience skin conditions that are similar to what one may experience from sun exposure. Tanning, darkening, and redness is a common occurrence. Some individuals may also experience inflammation and blisters. Dryness, flakiness, peeling, and itching of the skin may also occur. To minimize the damage, one should abstain from wearing tight clothing.

It is essential to cover the area to protect it from sun damage, but with loose clothing. Bandage, tape, and gauze may also be avoided. Your doctor must be consulted before using sunscreen. When washing the area, use a mild soap with lukewarm water. Do apply excessive heat or cold to the area. Use only prescribed medications and lotions for local application. In some cases, cornstarch also helps relieve itching.

Mouth Problems

Consult your dentist prior to starting your therapy. One of the primary radiation therapy side effects is changes in salivation, such as having thick saliva or a lack of saliva. Other side effects include difficulty in swallowing, stiffness of the jaw, and mouth sores. Your cancer specialist can give you the right advice to manage these conditions. When faced with mouth problems, it is a good idea to restrict acidic and spicy foods, tobacco, and alcohol. Further, brush your teeth thoroughly with a soft brush two times a day.

Hair Fall

Hair loss is one of the radiation treatment side effects when the treatment is administered to the scalp. Other types of cancer do not result in hair loss. Hair loss happens suddenly with hair coming out in clumps. Hair loss is reversible and hair grows back after therapy. The hair that grows back is thinner and with a different texture. Individuals who lose hair at the top of their heads may wear a hat or a wig to cover the exposed scalp and protect it from the sun.

Nausea, Vomiting, and Diarrhea

Nausea and vomiting is a common side effect after radiation exposure to the neck, head, and digestive tract. Inform the doctor of your condition, who may be able to prescribe medication and relaxation techniques to overcome the condition. Sometimes, your doctor may use biofeedback to control your nausea. Further, diarrhea may occur after a few weeks following therapy. Diarrhea can also be controlled using medication. Other techniques to control your diarrhea include avoiding high-fiber foods, getting enough potassium, and eating small meals frequently.

Problems with Eating

Radiation exposure to the neck, head, and digestive system may cause a loss of appetite. Even despite the loss of appetite, it is important to eat healthy to stay strong. It is necessary to consume five to six meals a day after radiation therapy. Further, adding healthy snacks and new recipes to your diet helps to maintain a good level of vitamins and minerals.

Fertility and Sexual Problems

Fertility problems are a common occurrence after radiation exposure to the pelvis. It may adversely affect your ability to have a child. Consulting your doctor about what to expect after the therapy is a good idea. Further, radiation therapy is not suitable for pregnant women and may cause harm to the growing fetus. Radiation to the pelvis may also stop periods or cause menopause problems.

Men who are exposed to radiation may suffer from low sperm count and sperm quality. A consultation with the doctor may help predict the outcome to determine whether it is advisable to use a sperm bank before the commencement of radiation therapy. In general, radiation to the pelvis affects its blood vessels and nerves in different ways, and only a doctor can help you predict the precise outcome and understand the best course of action.

Dealing with the Late Side Effects of Radiation Therapy

Late side effects take months and years and may not resolve spontaneously. However, late side effects are apparent only in some individuals. Some of these side effects include:

  • Patients may develop scar tissue that may affect the function of the lungs or heart.
  • Following pelvic radiation, side effects may include problems with the bowel and bladder, in addition to problems with fertility and sexual problems.
  • Radiation is one of the causal factors for cancer and may raise the risk of a second form of cancer. The nature of cancer developed after radiation depends on the area that was treated and the radiation that was applied to the area.

How to Help your Specialist to Improve Outcomes after Radiation

Whether you are planning on an external radiation therapy session or brachytherapy, it is important to see your doctor and discuss your health and treatment plan. You will then plan your simulation session with a radiation oncologist or radiation therapist. When administering radiation, your therapist may put marks on the skin to define the specific site for radiation, use body molds to keep your body in place, and use a face mask to keep the head and neck in the right position when administering treatment.

A specialist can answer most questions on what to expect from radiation therapy. Patients can help physicians achieve better outcomes for them by understanding and communicating the nature of their side effects:

  • Inform specialists about the side effects of radiation therapy accurately and on time.
  • Take medications as advised.
  • Rest adequately, maintain an active lifestyle, and eat healthy foods.
  • Strike the right balance between taking rest and pursuing the activities that interest you the most.
  • Make necessary adjustments to your schedule by informing your health status to your friends and family at home, and the HR department in your office.
  • Manage fatigue by speaking with a counselor to understand how to reduce stress, prevent focusing on fatigue, and conserve energy.
  • Prioritize your tasks and save energy so that you are in a position to tackle the important tasks before the other tasks.       
  • Discuss the long-term side effects of radiation therapy and weigh the risks and benefits of radiation therapy to achieve a better prognosis.

Even though radiation therapy has several side effects, it may be the best available option to treat some forms of cancer such as early-stage cancer. Sometimes, it may have to be combined with other treatments. In any case, the best approach is to discuss the pros and cons of the treatment strategy. A second opinion can help determine the risks and benefits of possible treatment plans in your specific case and assist in evidence-based healthcare decision-making.


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