I avoid packaged probiotics and buy freshly fermented kefir form my local food store. It tastes great (coconut or spirulina) and I use it for all the family.

How effective is it? I don't really know as it was the removal of key parts of my diet that brought me the most progress. All I can say is the way I perceive this disease suggests that I need probiotics to repopulate the good bacteria in my gut.