I don't know about a supplement, but I used to have incredible kidney pain and bladder symptoms til it got to be almost constant. thinking I had urinary tract infection I was always at the dr. but they did urine test after urine test and kept saying I had no infection. My chiropracter said "Do you think you might have a yeast problem?" I thought he was nuts, but when I got desparate enough, I went totally off of sugar and yeasts and I have not had the pain since - except if I go back to sugar. Mercury poisoned people usually have yeast problems - the yeast is protective in that it ingests mercury - protecting you from it - if I understand correctly. But the yeast comes with its own set of problems. Get rid of sugar, yeasts, and possibly even most fruit and milk from your diet. You also might be helped by getting rid of gluten (wheat, rye, barley, etc.)