Hi Candy,
I really don't know how common it is but I also have IBS that just keeps getting worse... I only have bowel movements once maybe twice a month... I know it's hard to believe but it's the truth.. Also, I used to never have bloating and pain in between those movements... But, in the last few months my stomach stays distended, I cramp until I double over, and nothing seems to help...
My doctor said it's a combination of the MS and the medication...