yu betcha. if you have slow motility, if you don't drink enough water, if you have diverticulitus, if you don't tolerate gluten (celiac disease) , many factors can contribute to fiber supps not working or causing more problems. try using food as your fiber: apple pectin, pears, pineapple, prunes, figs, brown rice, spelt or kamut flour and products, ground flax seeds, sea greens and so forth. g-