Help! I've been on Topamax and according to the warnings it says it "may" cause constipation. I have IBS with severe constipation; I've had it for 12 years. It's a constant battle. What's the word on Topamax causing constipation - is this a reality for some of you? Anyone in this forum taking it or have taken it in the past (or know of anyone who has) and has this problem? I think I need to switch to something else because it is making me miserable.