When I started Culturelle HS, I noticed some bloating and gas which went away within a couple of days. It doesn't hurt me, but I'm not sure it is helping,
When I started VSL#3, I noticed bloating and gas also which again went away within a couple of days. I've only recently started it, but I dare say I am seeing some benefit.
If you are worried about
how a probiotic will affect you, you can gradually move up to the dose that you want to take assuming it's not a once a day deal. With the VSL#3, I started with 1 a day and moved up from there to the 8 a day I am currently at.
Also, about
Primadophilus Reuteri by Nature's Way which pb4 mentions, there is also a version that does not have to be refrigerated in addition to the refrigerated version mentioned in pb4's post. You can see a full list of their probiotics on their website:
www.naturesway.com/?mid=4