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 should not be used in patients who have damage to the bowel wall.
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.