Dog eats carpet

Question
My sister has a mixed breed terrier that is around 11 years old.
The dog has taken to eating carpet from time to time. Right now
she is destroying the carpet in her current home. Do you have
a suggestion as to the reason and a solution? She brought it up
to her vet, but he dismissed it, and didn't give her any information.
Thank you for any information that you can give.

Answer
The eating of unusual substances is called pica. There really is no known reason for it.
Some have attributed diet to it, some say diet has nothing to do with it. It is most likely a combination of physiological and psychological issues.

Here is a general article about what pica could be:

http://www.petplace.com/article-printer-friendly.aspx?id=4038

I would suspect that at 11 years old this dog is suffering from some sort of cognitive disorder. This is something you need to address to the vet and if he dismisses it it's because he knows nothing about these issues and doesn't want to admit it.

Go to another vet. Ask for a referral if he refuses to address the issue or doesn't have an answer. Some vets deal with behavior and metal dysfunction issues in dogs differently.

Here is another article that addresses the possibility of it being cognitive:

http://www.aspcabehavior.org/printFriendly.aspx?aId=72

That is about all I can offer you. I hope you can find an answer before this dog ingests a large chunk of carpet when no one is around and chokes to death. That is what happened to a good friend of mine's dog at the age of 3 yrs.

Good luck and let me know what you find out.