Are there risks to colonoscopy prep procedures?
There are very few serious side effects to colonoscopies, a procedure in which a doctor examines the inside of the colon with a lighted scope, or viewing tube. But the commonly recommended preparations for the test, which is usually done under light sedation, can cause nausea, vomiting, painful cramping, dehydration, kidney damage, and fainting.
Colonoscopies save lives by catching precancerous polyps and removing them before they can become dangerous, said Dr. Anthony Kalloo, chief of gastroenterology and hepatology at Johns Hopkins Hospital. Overall, an estimated 155,290 Americans will be diagnosed with colorectal cancer this year, and 56,290 will die.
To prepare for the examination, patients must clean all fecal material out of the colon, a process many people find more unpleasant than the exam.
There are several ways to do this. One way is to drink a gallon of prescription solution such as GoLytely, Colyte, or NuLytely. They are effective at cleaning out the colon but can sometimes cause gastrointestinal upset, said Dr. Rosaline Barron, a gastroenterologist at Mount Auburn Hospital in Cambridge.
A second approach, which many patients find easier but which doesn't always cleanse the colon quite as well, Barron said, is to use Fleet Phospho-Soda, an over-the-counter liquid that the patient takes in two 3-tablespoon doses mixed with ginger ale. This method can cause problems for people who have kidney disease or congestive heart failure, making it ''basically a young and healthy person's prep," she said.
A third method is HalfLytely, which calls for drinking only a half-gallon, not a full gallon, of solution as well as taking two to four Dulcolax tablets. Again though, the colon may not get clean enough.
For people who really can't stand drinking the solution, there is a pill-only prep. The patient takes 28 to 32 pills of Visicol, but this carries the some risks and may not yield a clean enough colon.
JUDY FOREMAN
E-mail health questions to foreman@globe.com.
