Acral lick dermatitis, also known as lick granuloma, is a self-induced skin lesion. The
term acral refers to the legs and feet. Acral lick dermatitis mainly is a problem of dogs,
rarely cats. The dog continually licks at one area of the leg, producing hair loss, sores,
and thickening of the skin. Typical appearance is a raised, red, hairless, oval patch of
skin or skin lump found over the front surface of one leg. Occasionally, more than one
leg may be affected. The most common locations are over or near the carpus (“wrist”) of
the front foot or just below or above the hock on the rear leg. Breeds most likely to
develop acral lick dermatitis include the Doberman pinscher, Great Dane, Labrador
retriever, Irish setter, golden retriever, and German shepherd, but any breed of dog can
Males are affected twice as often as females. The condition may appear at any age;
however, most dogs are over 5 years of age when presented for treatment. Although
several conditions that cause discomfort of the skin can cause persistent licking (see
Diagnosis below), in many dogs with acral lick dermatitis no underlying problem can be
found. In these cases, acral lick dermatitis is considered a psychogenic disease; that is,
it is caused by a behavioral disorder. For example, sometimes excessive licking or
chewing can result from boredom or can be used as attention-seeking behavior;
sometimes anxiety is the stimulus for stereotypic behaviors like repetitive licking.
Stereotypic behaviors are excessive, repetitive behaviors engaged in to relieve
psychological distress such as boredom or anxiety.
Several other skin conditions may appear similar to acral lick dermatitis. These include
skin tumors, granulomas (masses due to chronic inflammation), and deep bacterial or
fungal infections. In addition, several conditions that cause pain or itching can be
involved in the development of lick granulomas, since dogs will lick areas where they
feel tingling or discomfort.
Depending upon the appearance of the skin lesion and your pet’s history, your
veterinarian may need to run several tests to check for similar conditions and underlying
disorders, including skin scrapings, bacterial or fungal cultures, and skin biopsies.
In some cases, x-rays may be warranted to look for joint or bone disease, such as
arthritis, or bone infections that can cause pain and therefore cause a dog to lick over
the painful area incessantly. A history of trauma or surgery in the area might indicate
possible nerve damage as a source of discomfort. A variety of conditions that cause
itching can contribute to the development of acral lick dermatitis; these include allergies,
skin infections, and skin parasites (fleas, mange, etc.).
If no underlying disease can be found, then by exclusion, psychogenic factors are
assumed to be the cause of the dog’s constant licking.
Therefore, the first step in evaluating a dog thought to have acral lick dermatitis is to
perform basic tests to assess for other contributory medical and skin conditions (above).
Once acral lick dermatitis is confirmed to be the problem, a very valuable form of
evaluation is consultation with a veterinary behaviorist or animal behaviorists. These are
veterinarians/ animal behaviorists who specialize in assessment and treatment of
behavioral disorders such as acral lick dermatitis. TheYour veterinarian should be able
to refer you to one of these animal behaviorists to better identify and correct the
psychological/behavioral trigger that is leading to the incessant licking.
Living with the Diagnosis
Acral lick dermatitis can be challenging to treat. Medications may help, either for direct
application, or, in the case of behavior modifying medications, as oral tablets. Often the
visible skin lesion is only the surface of the problem, and the root cause is psychological
or behavioral. Therefore, the frustration of dealing with a dog that is compulsively licking
needs to be met with an understanding that some sort of underlying trigger may exist
and that dealing with that trigger is critical to solving the problem.
Response to treatment depends upon correction of the underlying cause. Many cases
require long-term care at home and adjustment of treatments when the lesion
reappears. It is worth remembering that stressful changes in your pet’s life may
precipitate reoccurrence of the problem.
There are many approaches to treating acral lick dermatitis, and some trial and error is
usually needed to find the best treatment for an individual dog. Since deep bacterial
infections of the skin usually are present as well (secondary problem due to the damage
of licking), antibiotic pills are usually given for several weeks. The affected skin area can
be treated directly with a variety of medications, including topical treatments and
injections. Bitter-tasting topical solutions are sometimes applied to discourage licking.
Most treatments that are applied to the lesion are aimed at altering the sensation in the
skin. Agents used include corticosteroids, dimethyl sulfoxide (DMSO), capsaicin, anti-
inflammatory drugs, and antihistamines. Additional treatments aimed at reducing itching
or painful sensations include acupuncture, laser surgery, or cryosurgery. Removal of the
lesion with conventional surgery, laser surgery, or cryosurgery is also advocated by
Some degree of relief can also sometimes be brought about by frequently bandaging
the leg and/or placing an Elizabethan collar on the dog to break the cycle of licking-
Behavioral components of the condition also need to be addressed. Boredom can be
alleviated by increasing playtime, introducing another animal as a playmate, reducing
confinement time, or keeping the pet occupied with toys such as those with openings for
treats (e.g., Kong-type toys). Several behavioral modification training techniques can be
used. Stressful conditions should be eliminated, when possible.
Antidepressant and antianxiety drugs may also be helpful in some dogs, and these can
be prescribed by your veterinarian or a veterinarian specialized in behavioral medicine.
Be diligent and persistent with treatment. Hair regrowth and reduced compulsion to lick
happen very slowly (weeks to months).
Avoid blaming or acting exasperated with a dog with acral lick dermatitis. Unfortunately,
compulsive licking can truly be exasperating, but yelling at or punishing dogs for doing
this simply does not register with them and often can make them more compulsive,
which worsens the problem. In other words, harsh words and punishment for licking
behaviors tend to be totally counterproductive.
Don’t assume that the problem is entirely in the skin, or entirely in the dog’s mind.
Oftentimes, a combination of behavioral factors and skin factors is to blame for acral lick
Signs to Watch For
Persistent licking or chewing at one area on the foot or leg.
Hair loss, irritated skin, and eventually a raised, completely hairless, shiny, reddened
area of skin.
Because determining the best treatment of acral lick dermatitis often requires trial and
error, several visits may be necessary to determine the optimal combination of
treatments for your dog.
Once the right treatment is found, the visits become much less frequent—generally just