I'm also using Primadophilus reuteri and I haven't had any problems with bloating or gas. However, it has done nothing to help my flare. I just keep taking it b/c it hasn't had any adverse effects.
Could be the reason why I've noticed improvements from it is because it works in conjunction with the other naturals I take and I've changed my diet cutting out all junk and processed foods/beverages and I exercise regularly with cardio and weights.
Often it's a combination of things that make each supplement work that much better and everyone is different, what works for some doesn't necessarily work for all.