You don't really need to spend money on shedding ease type products. If your housing is correct and the air humidity, nutrition, etc is OK, your cham will shed just fine by itself. I am always very leery of spraying ANYTHING but water on a cham. It wasn't formulated for chams, they wouldn't have been exposed to such ingredients in the wild, and I don't want to take a chance that there is a bad reaction or eye trouble. It could be that your cham has a localized infection that is just now visible. Chances are it has been slowly developing for a while. Or, possibly he got it caught in screening or burned it? I think many of us find Polysporin rather than Neosporin works a bit better on herp skin, but either one is better than nothing in a pinch. Also, your vet could probably give you a sample of Silvadene ointment. It's commonly used to treat burns and will have good anti-infection effects too.