A kinder, gentler colonoscopy
Preparation for a colonoscopy could soon be substantially easier if research by a Detroit gastroenterologist is confirmed. Dr. Chetan Pai of the Henry Ford Hospital reported Sunday at the Digestive Diseases Week meeting in New Orleans that it may not be necessary to consume the large amounts of unpleasant liquids now required to prepare for the procedure, which will be a major relief to anyone contemplating it.
Colonoscopies are a highly effective method of both detecting and preventing colorectal cancer. A flexible tube is inserted through the rectum and a miniature television camera is used to view the entire inside of the colon. Polyps, precursors of tumors, can be snipped out when they are found. This procedure is relatively painless because it is typically done under sedation and the patient doesn't feel a thing. An estimated 146,000 cases of colorectal cancer are diagnosed each year in the United States and nearly 50,000 die from it. But early detection can sharply reduce the mortality.
Ah, but getting ready for it is another story. For the procedure to be effective, it is important to clear out all the fecal matter from the intestines. That is done by inducing diarrhea. In the past, that was done with phosphosoda, which was unpleasant to drink, but didn't require more than a couple glassfuls. But doctors found out that phosphosoda was dangerous, so now the laxative of choice is Go Lightly, a solution of polyethylene glycol. Generally, physicians recommend at least a gallon of the solution. But the solution is hard to swallow in adequate quantities, especially for older people. "Even my own family don't want to get colonoscopies" because the preparation is so unpleasant, Pai said.
Anecdotal evidence suggests that the problem can be avoided in part by using lubiprostone, a pill that is normally used to overcome constipation. Pai decided to conduct a clinical trial to see if it worked.
He enrolled 102 patients with an average age of 57 who were scheduled to have a colonoscopy. Half were given lubiprostone--one tablet two days before the procedure and one tablet with each meal the day before the procedure--and half a placebo. All were also given Go Lightly and told to continue drinking it until they achieved a clear bowel movement.
Those who took the lubripristone, sold under the brand name Amitiza, drank significantly less Go Lightly, Pai said. Some were able to consume as little as one 8-ounce cup. Physicians who didn't know which regimen the patients received found that the preparation quality was virtually identical for the two groups and that there was not any difference in the detection of polyps.
The study was funded by Sucampo Pharmaceuticals Inc., which manufactures Amitiza.
-- Thomas H. Maugh II