I'm not sure what this could be. I don't think it would be a sugar substitute, as these are large molecules that I wouldn't expect to pass through the skin. For most of us, sugar / carb cravings fall away dramatically after a few days, although it can be very unpleasant waiting for the "carb appetite" to wane. The biggest problem of course is that sugar is in so many things, including in things that you would not expect, such as savoury sauces. A patch to help control sugar cravings would be wonderful, but sooner or later we'd have to wean ourselves off of that as well.