I'm a little late reading this, but it caught my attention as my dog Toby got a "spring hot spot" for the second year in a row. I think he has some allergies related to things growing in the spring and he licks a spot bald on his "forearm".
I don't have any good ideas, my vet gave me an anti-itch/anti-inflammatory spray and I couple that with blocking access to the area (Toby has been wearing a modified shirt for the past week - the neighbors are starting to question us), therefore breaking the habit.
Anyway, the real reason I wanted to chime in was that I noticed a post about garlic. I'm no doctor or vet, so take this for what it is, but I just completed my master's (on Monday) and as part of that prepared a paper on the toxicity of common "table scraps" to dogs for my environmental toxicology class. It was interesting research, although I really only scratched the surface. Here's what to consider re: garlic...
Onions and garlic contain sulfur compounds that hydrolyze into thiosoulfinate
s when chewed then decompose into disulfides. The short version is that these cause anemia. While there are not many reported cases of garlic toxicosis, garlic contains more disulfides on a mass basis than onions - it is simply thought that dogs have less access to quantities of garlic than they may have to onion. This "onion/garlic toxicosis" can be lethal without treatment.
Symptioms include pale mucous membranes, rapid respiration and heart rate, lethargy, and onion odor on breath. Vomiting and diarrhea may also develop. There are certain dogs with genetic predisposition to being more sensitive to these compounds. But, currently reports indicate that signs of toxicosis may be evident in dogs fed onions weighing more than 0.5% of their body weight. There's no dose related data (that I could find) relating to garlic, again because it is less often reported.
So, for a 60 lb dog, 5 oz of onion could be an issue (60 lb x 16 oz/lb x 0.005 = 4.8 oz). I don't know how much a clove of garlic weighs, but the reports I read suggest it would take even less garlic.
So, like I said, I'm not a vet or an MD. Just an engineer who wanted to research something interesting for my last scholarly project ever! I think dogs are much more interesting than most engineering subjects, right???