Cancer Health Center

Anticipatory Nausea and Vomiting

Treatment of anticipatory nausea and vomiting is more likely to be successful when symptoms are recognized and treated early. Although antinausea drugs do not seem to be effective, the following may reduce symptoms:

• Guided imagery.
• Hypnosis.
• Relaxation.
• Behavioral modification techniques.
• Distraction (such as playing video games).

Acute/Delayed Nausea and Vomiting

Acute and delayed nausea and vomiting are most commonly treated with antinausea drugs. 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 frequently. Blood levels of the drug(s) must be kept constant to control nausea and vomiting effectively.

The following drugs are commonly given alone or in combinations to treat nausea and vomiting:

• prochlorperazine
• droperidol, haloperidol
• metoclopramide
• ondansetron, granisetron, dolasetron, palonosetron
• aprepitant
• dexamethasone, methylprednisolone
• marijuana
• dronabinol, nabilone
• lorazepam, midazolam, alprazolam
• olanzapine

Nausea and Vomiting Related to Constipation and Bowel Obstruction in Advanced Cancer

In patients with advanced cancer, constipation is one of the most common causes of nausea. To prevent constipation and decrease the risk for nausea and vomiting, it is important that a regular bowel routine be followed, even if the patient isn't eating. High-fiberdiets and bulk-forming laxatives with psyllium or cellulose require large amounts of fluid, however, and are not well tolerated by patients with advanced cancer. Laxatives that soften the stool or stimulate the bowel may be prescribed to prevent constipation, especially if the patient is being treated with opioids for cancer pain. The use of enemas and rectalsuppositories is limited to 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 require suppositories for regular bowel emptying. Enemas and rectal suppositories should not be used in patients who have damage to the bowel wall. (Refer to the Constipation section in the PDQ summary on Gastrointestinal Complications and the Side Effects of Opioids section in the PDQ summary on Pain.) Severe constipation may result in bowel obstruction.

Malignant Bowel Obstruction

Patients who have advanced cancer may develop a bowelobstruction that cannot be removed with surgery. The doctor may insert a nasogastric tube through the nose and esophagus into the stomach to temporarily relieve a partial obstruction. If the obstruction completely blocks the bowel, the doctor may insert a gastrostomy tube through the wall of the abdomen directly into the stomach to relieve fluid and air build-up. A gastrostomy tube also allows medications and liquids to be given directly into the stomach by pouring them down 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; or an expandable metal tube called a stent may be inserted into the bowel to open the blocked area. Injections or infusions of medications may be prescribed to relieve pain and/or nausea and vomiting.

Alternative Therapies for Nausea and Vomiting

Nausea and vomiting may be controlled without using drugs. The following may be helpful in relieving symptoms, especially for anticipatory nausea and vomiting, and may improve the effectiveness of antinausea drugs.

• Nutrition (see the Nausea section in the PDQ summary on Nutrition in Cancer Care for more information).
• Hypnosis.
• Acupuncture (see the PDQ summary on Acupuncture for more information).
• Acupressure.
• Guided imagery.