A newspaper based in Annapolis, Maryland has an “Ask The Vet” column. Someone wrote in to ask about tail-chasing by a dog. The vet replied with some good information on obsessive compulsive disorder in dogs as well as ways to combat the problem. Here’s the link:
The photo below is the leg of a dog with an obsessive licking problem. The dog has licked through the skin into the deeper tissues of the leg. These are really hard to heal. They simply won’t heal if the dog continues to lick, so an elizabethan collar is one of the strategies we usually have to employ.
thepetauthority 
I think most Dogs need a job to do, agility, walking, fetching, tracking activities. It takes a lot of effort to give your dog the occasions to do these things. If given a “job” to do many of these obsessive behaviors will be less. If a dog gets regular exercise they a tired and not bored. Sometimes you need to teach them a more acceptable behavior instead of the obsessive one. Distraction is a good thing to practice when they display these undesirable behaviors. There some pets that do require medication. I am not against using medication to improve your pets’ life, and yours. I agree that it is very hard to fit in that daily exercise, especially in the bad weather, but is part of being a pet owner. Dogs need to challenged mentally as well as physically. Two of the things I do is freeze peanut butter in a kong, and use an interactive puzzle that my dog finds enjoyable. I alternate these things when the weather is too bad to walk. I use alternate them so she doesn’t get tired of them. I really make an effort to exercise her whenever possible. I even set up a tunnel and a jump or two in the basement during the winter. It is an effort to find low calorie treats for these activities, so she doesn’t get too many calories when she is not getting exercise. I break up her favorite treats to help with the calorie intake. I make brushing her teeth is somewhat of an interactive game with her. I play with the toothbrush with her before I brush, making a game of getting it out of the drawer, I put a tiny bit of tooth paste on my finger and make her sit, down , roll over to get to lick the paste off my finger. Yes, it is a lot of work, but my timid Sheltie, Abby has come a long way since we rescued her. This past Christmas day she let several people she didn’t know very well pet her ! It makes all the work worthwhile. Linda Hutchinson
I’ll admit to a little nepotism, here, but Mom’s right on the money. Her dog displayed a LOT of anxiety and compulsive behaviors, along with quite a few undesirable behaviors like defecating in the house. She’s come a LONG way since she was adopted, thanks in large part to having jobs. Agility, puzzles, and trying to herd whitetail deer on her walks all engage her in a way that makes sense to her dog brain. It’s a struggle sometimes to realize that spoiling your dog is done best by letting them be a dog! All the better if you’ve got a smart dog that you can engage with more complex training. Never ever underestimate the power of “sit,” “stay,” “shake,” and “roll over,” however. These simple things, paired with a reward like petting or bits of treats, will make your dog a heck of a lot happier.
For even more information on engaging your dog, take a look at http://indoorpet.osu.edu/dogs/ . Great info!
There may be physical reasons for excessive licking, too. Kibeth, our Greyhound with LS disease, also licked her leg through the skin down into the tissue. The consensus was that the nerve compression in her spine caused a tingling sensation, which she tried to relieve by licking. It didn’t work, of course; but she kept licking anyway 😦
Pain is indeed another reason for chronic licking. We have to rule out painful conditions (as well as itchy things like allergies) before we can get to work on psychological conditions.
Thanks for commenting to help others, Chris. I know it’s tough to bring up sad memories.
-Hutch
As always, thanks for your understanding. It was hard to lose her, but we’re glad she’s not in pain anymore. Run in peace, Kibeth.