Most of the side effects of radiation therapy are limited to the area that received radiation. For example, a breast cancer patient may notice skin irritation on her chest, like a mild to moderate sunburn, while a patient with cancer in the mouth may have soreness when he swallows. Some patients who are having their midsection treated may report feeling sick to their stomach or diarrhea.
These side effects are related to damage to rapidly dividing cells. They are usually temporary and can be treated by your doctor. Side effects usually begin by the second or third week of treatment, and they may last for several weeks after the final radiation treatment. In rare instances, serious side effects develop after radiation therapy is finished. It is important to tell your doctor or radiation oncology nurse about any side effect.
The side effect most often reported by patients receiving radiation is fatigue, sometimes described as an "overall blah feeling." The tiredness patients experience is usually mild or moderate and it different for each patient. Fatigue may also relate to the area being treated and the other therapies, such as chemotherapy, the patient is receiving. Patients may be able to continue all or a portion of their normal daily activities. However, treating cancer often requires considerable mental and physical effort. Whenever possible, try to take time during your treatment to rest and relax. Ask your doctor about the specific side effects you should look for regarding your exact treatments.
If you experience discomfort or other symptoms during or after treatment, be sure to tell your radiation oncologist or radiation oncology nurse. They may be able to recommend strategies, prescribe medication or suggest changes to your diet to help.