I've used all three, Librax, Bentyl, and Donnatol.From what I've heard, it's basis is mostly decided by what works best for the patient. As in, if Librax isn't working, they'll try Bentyl, and vice versa.Did you say you're taking more than one of the three at once? I don't believe you're supposed to do that, but if the doc said to don't listen to me. I just know when I made the change, I was told to completely stop taking one before I started the other. The ingredients for all three are similar.Personally, I use Chlordiazepoxide/Clidinium caps, or the former Librax. Now Librax is methscopolamine and clidinium. The methscopolamine made my situation worse. That stinks, too, because I just love the flower it comes from.Basically, take what your body responds best to. Good Luck.