Popular Colonoscopy Prep Solution May Pose Kidney Risks

Mar. 28 -- TUESDAY, March 25 (HealthDay News) -- One of the most common bowel-cleansing preparations used by people who are about to have a colonoscopy can trigger both acute kidney failure and long-term renal damage in otherwise healthy patients.

New research suggests the risks of oral sodium phosphate solution and some oral sodium phosphate tablets are rare but real, particularly for elderly patients.

"People should be very cautious in the use of these agents because of their potential of causing kidney damage," said study author Dr. Anand Khurana, of the department of nephrology with the Scott & White Clinic at Texas A&M University in Temple, Texas.

The findings were published in the March 24 issue of the Archives of Internal Medicine.

Another popular prescription colonoscopy preparation -- polyethylene glycol solutions (PEG) -- was not the subject of the current study and does not appear to be associated with similar risks. Neither was the oral sodium phosphate tablet OsmoPrep, which has a lower sodium phosphate content than other tablets.

In 2006, the U.S. Food and Drug Administration put out an alert on oral sodium phosphate products, excluding OsmoPrep, recommending that they be "used with caution" among patients with impaired kidney function due to its high phosphate content.

The latest finding extends the concern to patients with no previous history of kidney trouble.

According to the American Cancer Society, colorectal cancer ranks third in the United States in terms of cancer diagnoses among both men and women. The organization estimates that about 150,000 people will develop the disease this year alone.

Typically, a colonoscopy is recommended for men and women over the age of 50 every 10 years as an effective way to screen for small growths called polyps and other signs of colorectal cancer. Some high-risk groups are encouraged to begin undergoing screenings at an earlier age.

The procedure involves the insertion of a slender and flexible lighted tube, fitted with a video camera, throughout the entire colon. A sigmoidoscopy relies on a similar but shorter tube to examine just the lower colon. Medication ensures that most patients feel no pain, and the screening is usually conducted on an outpatient basis.