I found Colloidal Silver to be very helpful with IBS related to mercury detox. If I'm not mistaken, mercury causes mutations in the gut bacteria which cause the loose stools. Metamucil didn't seem to help at first, but the silver did the trick.
I've read its important to take the silver not when the stomach is full of HCL, as that de-ionizes the silver. Best to take on an empty stomach or a few hours after a meal.