My mom had to take a boatload of IV antibiotics and antifungals for over a month, her PCP recommended the highest cfus I could find of probiotics (which was this one), as well as Bulgarian yogurt. She takes this every day - I'm not sure how we'd know if probiotics are working or not. Her GI doc said it certainly can't hurt, but that commercial probiotics tend to be "a drop in the ocean" of what we actually need. It's on auto-ship, easy to swallow. Capsule with powder in it.