Radiation therapy is used to treat cancer. Radiation occurs in nature, both as cosmic radiation from outer space and from naturally occurring radiation sources. The average chest x-ray, which uses radiation to take an internal picture of the body, exposes a person to the same amount of radiation a person is exposed to naturally in 10 days. This is considered a low dose of radiation, about 0.1 millisieverts. The radiation used in radiation therapy uses much higher doses, enough to kill cells in the body. Radiation therapy produces side effects, and it can be helpful to patients to understand and prepare for them.
Urinary and Bladder Effects
Patients receiving radiation therapy on the prostate or bladder may start experiencing problems after three to five weeks of radiation treatment and continue to experience symptoms two to eight weeks after its conclusion. These problems include trouble starting to urinate, problems with emptying the bladder, a burning pain while urinating or after emptying the bladder, incontinence, swelling in the urinary tract, bladder spasms and blood in the urine.
Throat Effects
People who receive radiation therapy to the chest or neck area can have side effects in their throats. These side effects are noticed two to three weeks after radiation therapy starts. Patients typically recover four to six weeks after radiation therapy ends. These changes include soreness in the lining of the throat, an inflamed throat, the feeling of having a lump in the throat and problems with swallowing.
Skin Effects
The side effects that affect skin can start a few weeks after therapy begins and usually end a few weeks after its conclusion, although some changes can last longer. Common changes include redness, an itchy feeling, dry and peeling skin or swollen skin. Radiation therapy can also kill skin cells faster than they can grow back, causing sores and ulcers to form.
Fertility and Sexual Effects
Infertility and sexual side effects can occur when there is radiation therapy to the pelvic area. Some effects can end after treatment, and some can be permanent. Men can experience impotence and infertility. Women can become infertile, also. Women can experience symptoms of menopause, pain or discomfort during sex, and vaginal itching and dryness.
Nausea and Vomiting
Radiation treatment to the stomach, colon, intestines or parts of the brain can cause nausea and vomiting. Nausea and vomiting can begin 30 minutes after the start of radiation therapy and last hours after the end of a radiation therapy session.
Mouth Effects
Radiation therapy to the mouth or neck can cause mouth sores---which can heal when therapy ends---and changes in taste, which can be permanent. Side effects also include dry mouth, mouth sores, thick saliva, tooth decay, jaw stiffness and infections of the teeth, tongue or gums.
Hair Loss
Hair loss from radiation therapy occurs only in the area receiving radiation therapy. Hair loss can begin two to three weeks after the start of radiation therapy. Hair can begin regrowing three to six months after the end of treatment, although in some cases the hair loss is permanent.
Fatigue
Fatigue is a common side effect of radiation therapy. While the onset of fatigue depends on many factors, including age, the period of fatigue can last six weeks to 12 months after the end of radiation therapy.
