"HOT SPOTS": Are annoying, but otherwise benign, patches of skin inflammation and/or infection. The cause is unknown, but there is some indication that there is a genetic suseptibility and or a pre-disposition to other allergies, most notibly food allergies. It is my own experience that certain dogs seem to get these more frequently, while others, housed together under the same conditions, never have had one. This is most curious and points to a genetic or allergy problem. In predisposed dogs, a warm hot climate combined with a dog which has not been regularly well-groomed seems to contribute.
Appearance: Invariabley, the dog has been biting or scratching at the "hot spot" for days before you will notice that the dog is "worrying" this area. There will be a clump of hair missing from this area and the skin underneath is characteristically reddened and even may have a light-greenish tinge to it. If you smell, this site, it will have a slightly sweet-offensive odor. This is all reminiscent of a Psuedomonas skin infection.
Treatment: I like to use "Betadine" (10% Povidone Iodine) antiseptic solution and pat it on the wound with gauze. I let it dry and then pat (or pour) on 3% Hydrogen Peroxide antiseptic solution and watch it bubble. I don't use a dressing over this mostly because the dogs will gnaw it off any way. Some dogs are very sensitive at these sites and for them, I mix the Betadine (1 part) with water (4 parts) adn put it in a spray bottle and spray it on the wound (no patting necessary). The HO can also be sprayed.
Occasionally, if the wound is not healing, I use a prescription strength corticosteroid cream (OTC 1% Hydrocort) to beat the inflammation. Some people use various antibiotic ointments and tea-tree (Malaluca) oil, but this seems less effective to me.