Its in mouthwashes, however. But no you want the concentrate that you mix with water. You MAY need to mix a new batch every time you use it, however. I've heard many times you absolutely do but last I heard there had been no real study on its effectiveness on Gram negative or positive bacteria after having been mixed with tap water after a couple weeks. I remember hearing, however, that if it is in distilled water then it should be able to last longer, but I again have not seen a comprehensive study on this.