Hello, I'm Dr Ralston, thanks for your question.
There could be several issues at play here. But, typically dogs lick their feet for one of three main reasons:
3. behavioral - OCD, attention seeking behavior
There is going to be a lot to talk about here. It's complicated. And I think that's why your question has remained on the board for so long. But, I am going to give it a go ok?
Let me know if you have questions and we can follow up on this.
A close inspection of the feet should tell you if an infection is present. Look for red or swelling. Smell the feet and see if they have a bad odor. Does Bonnie spend a lot of time in a dog run? OR on moist soil? This can lead to foot problems of course...
So, I definitely think that it could be allergies. Most dogs with allergies of any kind will benefit from a food change. I like Wellness a lot, and if your dog does too I would stick with it.
BUT, food allergy specifically causes itchy ears and itchy rears. So, this sounds like it is more contact dermatitis or inhallent allergies. Why dog's feet itch with allergies is anyone's guess. But, sometimes they do.
Be sure to dry the feet anytime she comes in from being outside. It could be that there is a secondary infection in the feet. Try soaking the feet in a solution of dilute betadine and water until it is a weak tea color. Do this once or twice daily for about 5-10 minutes each time. If there is a deep infection, or irritation, this should help to clear that up!
Otherwise you start thinking about behavioral issues. And this could be possible as well because she is licking the carpet. BUT, I don't think that is very likely. Most likely she starts to lick the feet and just gets kind of overzealous and keeps on licking, fur, feet, carpet....etc.
But let's say it could be behavioral :
They get to the point where they lick for comfort, but they just keep doing it.
But truly this can be a serious problem and a sign of stress.
There are medications which can also help break the anxiety. In dogs I have used one called Clomicalm with very good success.http://www.clomicalm.novartis.us/
Behaviors can be really hard to resolve as well
If a person changes their behavior quite suddenly we suspect something is wrong with them. If they are aware of the changes but unable to control them, they often seek medical help in the form of a Doctor that treats behavior problems. In humans that's a Psychiatrist, but in animals we refer to Veterinary Behaviorists.
This is a true specialty in Veterinary Medicine and these Doctors can help you diagnose the problem faster and get you to an acceptable answer faster as well. It is almost IMPOSSIBLE to give any help online with behavior. It is best dealt with a one on one approach of treatment and behavior modification.
I hope you understand.
The American College of Veterinary Behaviorists recommends the advice on finding an acceptable trainer How to select a trainer link
This link will help you find a Board Certified Behaviorist in your area Click here
Here are some links I also found for you that might be helpful as well. I think you might get some good insight from them :Click here for information on OCDHow to ease pet stress
Please accept my offer to help. Good luck.