This is a question without a simple answer. Anytime there is a "behavior" involved, it is most important to first rule out an underlying medical reason for the behavior. If all medical concerns are ruled out, then the problem can be approached as a behavioral one, and behavior modification techniques can be employed. A foot licking problem can start out as a medical one and later become a habit or compulsive behavior. Your veterinarian will be the only one to fully determine what is going on with your dog's feet, but here are some things your veterinarian will want to know and will be looking for on examination:
Are the feet red, swollen, or crusty/flaky?This could be indicative of a local irritant (such as deicer) or inflammation/infection from bacterial, fungal and/or parasitic sources.
Depending on what your veterinarian finds on examination, treatment to stop this behavior will be aimed at the underlying cause. For cases of allergy or infection, there are medications and/or dietary changes that can be made to assist with the problem. In situations where pain is the underlying cause, that should be dealt with directly to alleviate the licking. Growths or abscesses are usually treated surgically. Pet owners should always be vigilant about environmental hazards to feet; such as deicing compounds in the winter and very hot pavement tar in the summer.
Behavioral modification to stop paw licking and chewing, like any behavioral modification, takes time, patience and consistency. There are several topical products that can be used to discourage this behavior (bitter, hot taste, etc.). Physical restraint, such as an e-collar is often used for medical conditions to allow the foot or paw to heal and thus take away the inciting cause to lick. Distraction is also a good technique: playing games, offering other toys and incentives to keep your dog occupied coupled with positive reinforcement will help break the cycle.
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