here's some info . from Jean Donaldson.
The question
of whether her problem is a physical or mental one is complicated.
What kicks off ALD is often completely different from
what ends up maintaining the problem. A classic case gets up and
running when the dog has some physical condition such as a skin
allergy or fungal infection, ringworm, scabies, demodex, nerve
inflammation, arthritis, or even local tumors. Then, even if the
primary physical problem fades or is resolved, the licking carries on.
At this point the problem is considered a compulsive disorder (it's
not known whether dogs have obsessive thoughts, so it's just called
"compulsive disorder" in dogs rather than obsessive-compulsive
disorder)
Compulsive disorders can be the end result of dogs trying to cope
with frustration and conflicting motivation. In the frustration
department, consider the life of many dogs: a fairly steady stream of
not being able to access things they see behind fences and beyond
the end of their leashes. Conflict might look like a dog who is
simultaneously curious and afraid of the same thing. Another example
is a dog who is sometimes greeted and sometimes punished
by his owner in similar situations, such as when the owner arrives
home or approaches. The dog feels a simultaneous urge to greet and
avoid, which, if you think about it, can be crazy-making.
The acute feeling of frustration or conflict might result in a redirected
or displaced behavior. Dog trainers will tell you about
getting redirected bites when grabbing the collar of a dog who is
highly motivated to fight. The trainer is not the real target, but is
unloaded on because she is handy and in the way. Displaced behavior,
by contrast, is seemingly irrelevant to the context in which
it occurs. The dog is conflicted so neither approaches nor avoids,
but chases his tail instead. If the frustration or conflicts are chronic
enough, the behavior becomes more entrenched and at a certain
frequency gets dubbed a compulsive disorder. Once it's at this stage,
it'll happen whenever the dog feels stressed or is bored and, in the
most severe cases, virtually all the time the dog is not otherwise
occupied.
Aside from acral lick dermatitis, also known as lick granulomas,
compulsive disorders include (imaginary) fly-catching, flank sucking,
whirling in place and tail-chasing, pacing, chasing shadows or
imaginary objects, staring into space, excessive drinking, and selfmutilation.
Which particular behavior a given dog ends up with is thought
to be at least partly genetically predisposed. For instance, breed
over-representations include flank sucking in Dobermans, fly-catching
in Miniature Schnauzers, and whirling in Bull Terriers. Lick
sranulomas pop up more often in Dobies, German Shepherds, and
Danes, such as Muffin. Another potential determination of a dog's
particular "choice" of compulsive disorder has to do with whether
the original kick-off stressor was a repeated conflict or due primarily
to the particular frustration of extremely low stimulation, i.e.,
boredom. Dogs who experience chronic conflict tend toward the
high energy disorders such as tail-chasing or "popping" (jumping
up and down in place) and then, once the disorder is entrenched,
proceed to engage in their compulsion whenever they get amped
up. Self-directors—like Muffin—might commence due to one of
the physical causes described earlier, or conflict, and then carry on
at times of low stimulation.
Another thing that can maintain ALD in particular is a vicious
cycle of endorphin addiction. Once the dog has created a significant
sore, the body releases its natural painkillers. If the dog ceases
licking, the endorphins are not produced and the dog literally experiences
withdrawal. So, the dog licks to keep the sore alive in order
to produce the endorphins.
Before doing anything else, get Muffin to your vet for a thorough
physical exam, bloodwork, urine, and a dermatology work-up.
Depending on the outcome of these, s/he may want further diagnostics.
If the ball is passed to the behavior court, you should increase exercise
and mental stimulation. Depending on Muffin's exercise tolerance—
check with the vet on this—commence a daily bout of hard
aerobic exercise. Perhaps more importantly, Muffin needs a Job to
do. If there are courses in your area, enroll in something like a tricks
class, musical freestyle, or advanced obedience. It doesn't matter if
Muffin is a huge talent at the activity: the process is the product.
We want Muffin's mind challenged.
An important caveat: be sure the course is taught using a punishment-
free method. Regardless of what your personal philosophy is
of dog training and regardless of any proposed merits of training
dogs with correction collars, in the case of compulsive disorder
resolution, removing punishments from the dog's life is a cornerstone
of treatment. If there are no courses in your area, get a book
on clicker training and learn to free-shape behavior. Karen Pryor's
Don't Shoot the Dog is excellent.
It would also be a good idea to invest in chewies and puzzle toys—
stuffed Kongs™ and activity balls where Muffin must roll them
around in order to extract part of her meal ration. There's even a
new device out that dispenses stuffed Kongs at pre-programmed
intervals so Muffin can get unstuffing projects throughout the day
when she's alone.
Teach and reinforce a behavior that is incompatible with forepaw
licking. A good example would be fetching and chewing on a specific
bone or resting her head on a cushion at times when she might
lick. This is another place where clicker expertise might come in
handy.
You and your husband must bone up on ways to communicate with
Muffin in a consistent manner, specifically to avoid any sometimespunish-
sometimes-not conflicts that may occur. A well-run training
course will teach you how to do this. Once again, be sure to screen
carefully to be sure the course employs strictly reprimand and punishment-
free techniques.
Consult with your veterinarian on a potential course of anti-obsessional
medication. The tri-cyclic anti-depressant clomipramine
(Clomicalm) and some drugs in the selective serotonin reuptake
inhibitor class, such as fluoxetine (Prozac) and fluvoxamine (Luvox),
have track records at working well in conjunction with the
behavior modification measures listed above. In the case of ALD,
hydrocodone, the narcotic agent found in Vicodin, has proved
helpful in certain cases. Aside from providing pain relief, it has been
speculated that an exogenous opiate source interrupts the vicious
endorphin cycle. Using similar logic, opiate antagonists pre-empt
die endorphin pay-off and render the behavior unreinforcing. This
therapy is usually considered a last resort