Radiation therapy can cause after effects because the radiation can damage healthy tissue near the area being treated, according to the National Cancer Institute. The occurrence and severity of after effects vary on an individual basis. The odds of having severe problems are increased if radiation is combined with chemotherapy; some patients develop problems months or years after completing therapy.
Skin Problems
Skin problems can occur and can include dry skin, peeling, itching and blistering in the area being treated, according to the NCI. This is due to the radiation damaging healthy skin. Skin problems typically develop a few weeks after treatment begins and clear up a few weeks after treatment is over. The use of prescription creams and careful skin care can help manage or prevent some of these problems. In some cases, however, the skin may never return to normal and may remain darker and thicker than surrounding skin, according to the American Cancer Society. Some patients also have difficulty healing wounds in the treated area.
Fatigue
Fatigue can be mild or extreme and include feelings of weakness, exhaustion or slowness, according to the NCI. It can be caused by anemia, infection, medication, stress, depression and anxiety. It typically develops during treatment and lasts six weeks to a year after treatment. But some patients never recover their previous energy levels, according to the American Cancer Society. Patients can sometimes manage fatigue with additional sleep and rest during the day and by increasing exercise. Some patients need to treat fatigue with medication.
Other After Effects
Depending on where the radiation treatment is targeted, some patients may also experience other after effects, according to the NCI. These can include diarrhea, nausea and vomiting, urinary problems, hair loss in the area being treated, mouth problems like dry mouth or cavities, difficulty swallowing, sexual changes, and swelling. These difficulties usually clear up about two months after radiation treatment ends.
Late Effects
Some after effects do not occur until six months or more after treatment has ended, according to the NCI. These can include infertility, joint problems, swelling in the arms and legs due to damaged lymph nodes and mouth problems. The kinds of late effects that occur depend on what part of the body was treated and how high a dose of radiation was used. There is also a risk that the radiation will cause a second cancer to develop years down the road.
