My father ended up on months-long rounds of antibiotics and started taking probiotics as a result. He also said it helped some similar digestive problems he's had for years.
That's the thing that gets me with probiotics/packaging: they list these counts that can vary widely and are sometimes seemingly astronomical.
It kind of implies that if some is good, then more is better. I've thought that there is certainly some level at which it's not good for you.
Logically, if a certain dosage is produced, then you assume it to have some therapeutic effect. So, adding an order of magnitude to a therapeutic dosage of something wouldn't seem universally harmless.
What I'm trying to get at is a low dosage might mean the little critters take a while to reach a good population, while a high dosage might be what's needed to discourage growth and encourage their reactions.
I'be personally used acidophilus lactobacillus after an oral yeast infection which I got after taking preventative antibiotics (took pretty much everything - azithromycin, flucloxacillin and ciprofloxacin) for a severe bout of reactive arthritis and it seemed to make a difference. However I was still very messed up for at least 6 months.