Has anyone else found that calcium can stop working after a while? Ive been taking it for about a month and a half with great success but its effectivenes seems to be declining. Is this normal? should I continue to take it? Is there anything else that workss so well. Ive heard a lot about colisted Id like to get some but you seem to need to convince your doctor Of its effectiveness for ibs. Has anyone come across some useful information on the internet relating to ibs?