Just a suggestion - My Lab/GS/Husky mix had itching issues and we put Gold Bond powder on the itchey areas and the areas cleared up. This may give your dog some itching releif untilyou get to the vet.
Itchy skin and licking in dogs seems to always be correlated to allergies. The vast majority of the dog food out there contain grains...which is a major allergen to many dogs. Try a grain-free food, or at least food that does not contain corn. Our Aussie, Buster, licked his feet to the point that they were bald when he was on a dog food that contained corn. None of the allergy meds. worked for him. Now that we read ingredient labels, the licking has stopped. We didn't pay for the expensive allergy testing either...we just did our research on how crappy most dog food is (even the stuff the vets recommend).
I know a lot of the grain-free dog foods are expensive. However, veterinary bills are more expensive. If it were me, I'd rather pay for a more expensive dog food then shell out money on allergy meds, antibiotics, and steroids that may or may not be fixing the problem. Those are band-aids...not real solutions.
Good luck on your dog's problem...the licking drove us all crazy!
We had an Irish setter that had chronic skin issues. She was a picky eater too.
We switched her over to a raw meat diet and it made a big difference in her coat/skin. We fed raw chicken, pork, lots of venison and some dried fish.
I do think a lot of the problems our dogs have are a result of the grain in thier diet. It's so hard to find dog food that doesn't have it as a first or second ingredient.
Benedryl will only cover up symptoms, not solve it. Its okay to use for symptom relief, but you have to get to the bottom of the cause. If you have not had it done already, go to a vet and have a skin scraping performmed & examined. This will tell you if it's a bug problem or not. If it is not, it is pretty certain that it is an allergy. Dogs (and people) can be alergic to external things (like detergents, chemicals, pollen and mold) or internal (things they ingest).
My bro has a Bull Terrier, this breed is known as the most allergic breeds on the planet. After a while we discovered that he is allergic to some protiens. He can only eat pork, which is very unusual. To find out what your dog is allergic to, you will have to stop feeding him any prepared dog food. most of these prepared dog foods are made up of the most common allergens for dogs: Corn, Soy, Wheat, and certain chemicals and preservatives. My brother makes his dog food, and since this time, the dog has had no more health problems. Prior to this, the dog was constantly ill and cost him thousands of dollars to treat. I reccomend you buy a book with simple ways to prepare dog food at home. Choose a simple food, made of the things your dog does not react to. Do you know which meats the dog is allergic to? If you do, feed only that for 2 weeks, or until his sympotoms subside. After that, you can add things to his diet on at a time. Usually only one thing a month. If something causes a reaction, put it on his "no" list. Finding out what the dog reacts to can take years. Also, initially your dog may react to everything because his immune system is hyperactive, and sensitive to everything. I will PM you with some book/recipie info.