Most of my co-workers in the supplement industry would never suggest psyllium (the active ingredient in Metamucil) for IBD suffers. It is known in the industry to cause "plugging" in the GI tract. In other words it can cause temporary blockages, sometimes in healthy people. I suppose it could contribute a bleed, if it plugged in the wrong place (like near existing scaring or ulcerations) and distressed the gut. There is a good amount of info at the following link, but keep in mind that this web site sells Heathers products, and may not be very objective.
That said, my personal experience seems to fall in line with this, and my customers with Crohn's, UC, and other GI issues swear by this product. We discontinued this at our store and had to bring it back by popular demand.
Any dietary fiber can and will cause plugging if you are deficent in Magnesium. Magnesium is necessary to draw moisture to the bowel. I have sold colon cleanse products to customers who have returned them because of bloating and gas combined with "C". They swear to me that they are drinking the 6-8 glasses of water a day that the products require. Some take the products back home with them, and add a Magnesium tablet at bedtime then do fine. An apple every day is a good choice for anyone who cannot or won't use supplements.
Post Edited (Margie11) : 1/19/2009 4:52:10 PM (GMT-7)