In late 2008, the Food and Drug Administration (FDA) issued warnings about bowel cleansing formulas commonly used before medical procedures, such as colonoscopies.

Here's what you need to know.

What's the Warning?

Many bowel cleansing products are made from Oral Sodium Phosphate (OSP). The FDA warns that these phosphate-based preparations may cause rare, but very serious, kidney damage. They can also negatively interact with certain medicines.

Bowel preparation products may be prescription or over-the-counter, where they are most commonly known as laxatives. Common prescription OSP products include Visicol and OsmoPrep.

Who's at Risk?

You may be at risk if you:

  • Are over 50
  • Have kidney disease
  • Have a bowel obstruction or colitis
  • Are taking medications that effect kidney function, such as blood pressure drugs or those for heart or kidney failure
  • Are taking non-steroidal anti-inflammatory drugs such as Ibuprofen

Children under 18 should not use these products.

What is the Result of the FDA Warning?

The FDA has asked manufacturers to include stronger warnings on their packaging and a patient medical guide. It has also instructed manufacturers to conduct additional clinical trials to study the safety of these products.

What Should You Do?

You may undergo colonoscopies or other medical procedures that involve the large intestine. In preparation for these procedures, your physician will provide products and instructions for cleansing, or flushing, your bowel the day before. Furthermore, as a Crohn's patient, you may be taking anti-inflammatory drugs, which as you can see from the list above, is a risk factor.

The incidence of kidney damage following use of these products is rare. However, if you have any of the risk factors, discuss them with your physician before using prescription or over-the-counter Oral Sodium Phosphate bowel cleansing products.