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Nausea and Vomiting (PDQ®)

Patient Version
Last Modified: 12/01/2011

Radiation Therapy and Nausea and Vomiting

Key Points for This Section


Radiation therapy may cause nausea and vomiting.

Radiation therapy may cause nausea and vomiting, especially in patients who are receiving radiation therapy to the gastrointestinal tract, liver, or brain. The risk for nausea and vomiting increases as the dose of radiation and the size of the area being treated increase. Nausea and vomiting caused by radiation therapy usually occur one-half hour to several hours after treatment. Patients may have fewer symptoms on days they do not have radiation therapy.



Glossary Terms

dose (dose)
The amount of medicine taken, or radiation given, at one time.
gastrointestinal tract (GAS-troh-in-TES-tih-nul trakt)
The stomach and intestines. The gastrointestinal tract is part of the digestive system, which also includes the salivary glands, mouth, esophagus, liver, pancreas, gallbladder, and rectum.
liver (LIH-ver)
A large organ located in the upper abdomen. The liver cleanses the blood and aids in digestion by secreting bile.
nausea (NAW-zee-uh)
A feeling of sickness or discomfort in the stomach that may come with an urge to vomit. Nausea is a side effect of some types of cancer therapy.
radiation therapy (RAY-dee-AY-shun THAYR-uh-pee)
The use of high-energy radiation from x-rays, gamma rays, neutrons, protons, and other sources to kill cancer cells and shrink tumors. Radiation may come from a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy). Systemic radiation therapy uses a radioactive substance, such as a radiolabeled monoclonal antibody, that travels in the blood to tissues throughout the body. Also called irradiation and radiotherapy.
symptom (SIMP-tum)
An indication that a person has a condition or disease. Some examples of symptoms are headache, fever, fatigue, nausea, vomiting, and pain.
vomit (VAH-mit)
To eject some or all of the contents of the stomach through the mouth.