Viberzi was a godsend when I started on it 6 years ago - huge improvement. Last couple of years, not so much, and I almost discontinued, but decided to stay on it with a consistent dose of 200 mg daily instead of varying dose depending on how well I was doing. That has helped a lot so far. If you have IBS D or M, it's well worth trying if you can afford the drug and don't have gall bladder problems.