I suffer from Interstitial Cystitis which causes urinary frequency and burning. I had tried other probiotics with only slight relief. I ran out of my regular probiotic and purchased Purple Probiotic from a natural foods store because they were inexpensive and I only needed a small bottle to take on a trip. Much to my surprise, these were much more effective than the brand I had been taking, and the burning subsided. I live outside of the U.S. now and wasn't able to have these shipped to me, so I shipped four bottles to a friend in the U.S. who brought them to me a few weeks ago. I've been taking them regularly, and they are working great.