I was diagnosed IBS-D in about 1991 and tried Modulon which had no effect. For the next 5 years i maintained a very strict diet (only simple natural sugars from fruit, vegetables and meat, no dairy, no potatos, no gluten/bread, no processed food at all) and again no result. An anti-Candida effort failed. Calcium, same. I started reading this BB in 99? until in 2001 a number of users described sucess with Cholestyramine which i believe is the same as Questran. I like the fact that more than one person had success, no one was selling me anything and all the info described it as harmless and without any major side effects so i tried it. It does not eliminate 100% of my symptoms but it is well worth it for me.