i used it for about a month after i noticed our cats teeth were getting more and more discolored after switching to mostly all wet food (and us not brushing most of their teeth didn't help matters of course). I saw no real affects from it in that time other than i realized one day that tux's BG had been continuing to slowly get elevate more each couple days since using it so we stopped using it...however i did go find out if was safe for diabetic cats before using it and they said it was safe so who knows. i now use their antiseptic gel 2-3 times a week instead, didn't notice a BG issue with the gel and did notice it actually helping the cats i use it with, two of them are in the early stages of stomatitis/gingivitis and when i use it once every day with them, their gum lines stop being inflamed by a lot.