I have not yet tried Three Lac, but have been a candida sufferer for a number of years. I am presently taking a garlic supplement which is causing extreme die-off, more than any other product that I have tried, and believe me I have tried a few. One of my symptoms is the lower back pain as well, which I know to be the kidneys, and I do believe it is due to the cleansing affect as well as the extra toxic overload being dumped into the system with the die-off. I have found great relief using the herb uva ursi, which can be purchased at any health food store. This helps along the cleansing process giving the kidneys the extra support, and also relieves the lower back pain. I also agree with the person who suggested you work on getting the bowel moving. Psyllium is a good fiber product, but you may need extra help while your body is eliminating the yeast.... cascara sagrada, senna..... any health store can steer you in the right direction with this. colonics and temporary enemas may be very beneficial for a time.... Hang in there, you are on the right track...