my dog seems to have somekind of skin rash or irritation in which he can not stop biting and scratching himself it is located on his upper front legs, chest and lower legs. it looks raw and blistering. it feels hard to the touch. it is not fleas. i have had that problem in the past and i take all the proper steps to prevent infestaion. in fact i think i might have caused the problem. he started scratching i did not see any fleas but i gave hime a bath using zodiac flea shampoo the next day he scratched again so i sprayed him with zonk-it flea spay(i'm kind of a nut about fleas) i did spray him several times but i never saw a single flea( which in the past i have aways seen some) then it came to me maybe it is a skin condition due to the pestisides in the products i used. last night i gave him a bath with a mild soap to try to wash skin of it.is this the problem??? what should i do?? should i get one of those cones that go around his neck so he does'nt bite himself??