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This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http://cancer.gov or call 1-800-4-CANCER.
Nausea and vomiting are serious side effects of cancer therapy.
Nausea is an unpleasant wavelike feeling in the back of the throat and/or stomach that may lead to vomiting. Vomiting is throwing up the contents of the stomach through the mouth. Retching is the movement of the stomach and esophagus without vomiting and is also called dry heaves. Although treatments have improved, nausea and vomiting are still serious side effects of cancer therapy. Some patients are bothered more by nausea than by vomiting.
Nausea and vomiting must be controlled to maintain the patient's treatment and quality of life.
It is very important to prevent and control nausea and vomiting in patients with cancer, so that they can continue treatment and perform activities of daily life. Uncontrolled nausea and vomiting can cause the following:
There are four types of nausea and vomiting that are caused by cancer therapy:
Anticipatory nausea and vomiting: If a patient has had nausea and vomiting after the previous three or four chemotherapy treatments, he or she may have anticipatory nausea and vomiting. The smells, sights, and sounds of the treatment room may remind the patient of previous times and may trigger nausea and vomiting before a new cycle of chemotherapy has even begun.
Acute nausea and vomiting: Usually happen within 24 hours after beginning chemotherapy
Delayed nausea and vomiting: Happen more than 24 hours after chemotherapy. Also called late nausea and vomiting.
Chronic nausea and vomiting: In patients with advanced cancer, chronic nausea and vomiting may be caused by the following:
Chemotherapy and radiation therapy are the most common causes of nausea and vomiting in patients being treated for cancer.
Nausea is controlled by a part of the central nervous system that controls involuntary body functions (like the heart beating). Vomiting is a reflex controlled by a vomiting center in the brain. Vomiting can be triggered by smell, taste, anxiety, pain, motion, poor blood flow, irritation, or changes in the body caused by inflammation.
The most common causes of nausea and vomiting are:
Many factors increase the risk for nausea and vomiting.
Nausea and vomiting are more likely if the patient:
Anticipatory nausea and vomiting may occur after several treatment sessions.
Anticipatory nausea and vomiting occur in some patients after they have had several courses of treatment. This is caused by triggers, such as odors in the therapy room. For example, a person who begins chemotherapy and smells an alcohol swab at the same time may later have nausea and vomiting at the smell of alcohol alone. The more chemotherapy sessions a patient has, the more likely it is that anticipatory nausea and vomiting will develop. The following may make anticipatory nausea and vomiting more likely:
The earlier that anticipatory nausea and vomiting is identified, the more effective treatment may be.
Treatment of anticipatory nausea and vomiting is more likely to work when symptoms are treated early. Although antinausea drugs do not seem to help, the following types of treatment may decrease symptoms:
Psychologists and other mental health professional with special training in these treatments can often help patients with anticipatory nausea and vomiting.
Acute and delayed nausea and vomiting are common in patients being treated for cancer.
Chemotherapy is the most common cause of nausea and vomiting that is related to cancer treatment.
How often nausea and vomiting occur and how severe they are may be affected by the following:
Acute nausea and vomiting are more likely in patients who:
Delayed nausea and vomiting are more likely in patients who:
Acute and delayed nausea and vomiting are usually treated with drugs.
Acute and delayed nausea and vomiting are usually treated with antinausea drugs. Some types of chemotherapy are more likely to cause acute nausea and vomiting. Drugs may be given before each treatment to prevent nausea and vomiting. After chemotherapy, drugs may be given to prevent delayed vomiting. Some drugs last only a short time in the body and need to be given more often. Others last a long time and are given less often.
Ginger is being studied in the treatment of nausea and vomiting.
The following table shows drugs that are commonly used to treat nausea and vomiting caused by cancer treatment:
Nausea and vomiting in advanced cancer has many causes.
Patients with advanced cancer commonly have chronic nausea and vomiting, which can decrease the quality of life. Nausea and vomiting related to advanced cancer may be caused by the following:
Treatment of nausea and vomiting in advanced cancer includes ways to keep bowel habits regular.
In patients with advanced cancer, constipation is one of the most common causes of nausea. To prevent constipation, it is important that a regular bowel routine be followed, even if the patient isn't eating. Laxatives that soften the stool or stimulate the bowel may help prevent constipation, especially if the patient is being treated with opioids for cancer pain. Patients with advanced cancer usually cannot handle high-fiber diets or laxatives with psyllium or cellulose that need to be taken with a lot of fluids.
Enemas and rectal suppositories are used for short-term, severe episodes of constipation. Patients who have a loss of bowel function because of nerve damage (such as a tumor pressing on the spinal cord) may need suppositories for regular bowel emptying. Enemas and rectal suppositories are not used in patients who have damage to the bowel wall. (See the Constipation section in the PDQ summary on Gastrointestinal Complications and the Side Effects of Opioids section in the PDQ summary on Pain.)
Nausea and vomiting are sometimes caused by a blocked bowel.
Patients who have advanced cancer may have a blocked bowel caused by a tumor. If the bowel is partly blocked, the doctor may put a nasogastric tube through the nose and esophagus into the stomach to make a temporary passage. If the bowel is completely blocked, the doctor may insert a gastrostomy tube through the wall of the abdomen directly into the stomach to relieve the build-up of fluid and air. Also, medicines and liquids can be given directly into the stomach through the tube.
Sometimes, the doctor may create an ileostomy or colostomy by bringing part of the small intestine or colon through the abdominal wall to form an opening on the outside of the body. For certain colorectal blockages, an expandable metal tube called a stent may be put in, to open the blocked area.
Medicines may also be used to treat nausea and vomiting and relieve pain.
Treatment without drugs is sometimes used to control nausea and vomiting.
Non-drug treatments may help relieve nausea and vomiting, and may help antinausea drugs work better. These treatments include:
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.
The PDQ cancer information summaries are reviewed regularly and updated as new information becomes available. This section describes the latest changes made to this summary as of the date above.
Editorial changes were made to this summary.
Physician Data Query (PDQ) is the National Cancer Institute's (NCI's) comprehensive cancer information database. The PDQ database contains summaries of the latest published information on cancer prevention, detection, genetics, treatment, supportive care, and complementary and alternative medicine. Most summaries come in two versions. The health professional versions have detailed information written in technical language. The patient versions are written in easy-to-understand, nontechnical language. Both versions have cancer information that is accurate and up to date and most versions are also available in Spanish.
PDQ is a service of the NCI. The NCI is part of the National Institutes of Health (NIH). NIH is the federal government's center of biomedical research. The PDQ summaries are based on an independent review of the medical literature. They are not policy statements of the NCI or the NIH.
Purpose of This Summary
This PDQ cancer information summary has current information about the pathophysiology and treatment of nausea and vomiting (emesis) (N&V). It is meant to inform and help patients, families, and caregivers. It does not give formal guidelines or recommendations for making decisions about health care.
Reviewers and Updates
Editorial Boards write the PDQ cancer information summaries and keep them up to date. These Boards are made up of experts in cancer treatment and other specialties related to cancer. The summaries are reviewed regularly and changes are made when there is new information. The date on each summary ("Date Last Modified") is the date of the most recent change.
The information in this patient summary was taken from the health professional version, which is reviewed regularly and updated as needed, by the PDQ Supportive and Palliative Care Editorial Board.
Clinical Trial Information
A clinical trial is a study to answer a scientific question, such as whether one treatment is better than another. Trials are based on past studies and what has been learned in the laboratory. Each trial answers certain scientific questions in order to find new and better ways to help cancer patients. During treatment clinical trials, information is collected about the effects of a new treatment and how well it works. If a clinical trial shows that a new treatment is better than one currently being used, the new treatment may become "standard." Patients may want to think about taking part in a clinical trial. Some clinical trials are open only to patients who have not started treatment.
Clinical trials are listed in PDQ and can be found online at NCI's Web site. Many cancer doctors who take part in clinical trials are also listed in PDQ. For more information, call the Cancer Information Service 1-800-4-CANCER (1-800-422-6237).
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National Cancer Institute: PDQ® Nausea and Vomiting. Bethesda, MD: National Cancer Institute. Date last modified <MM/DD/YYYY>. Available at: http://cancer.gov/cancertopics/pdq/supportivecare/nausea/Patient. Accessed <MM/DD/YYYY>.
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Last Revised: 2013-08-23
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