There is an herbal formula called Herbal Detox by Herb Pharm. You can get it at most any health food store. My acupuncturist recommended it. About a week after I began taking it, I started seeing black sand in the toilet after I peed. I told the acupuncturist about this and he said, "Good! Those are kidney stones!" I had a bunch of tests after that and the doctor said my kidneys are very strong.