older dog becoming more agressive

Question
Mia is a shar-pei, 12.5 years of age, diet is Science diet for adult
dogs, and has always been an inside dog.  She is tending to go
after the cats (we have always had cats around her ever since
she was a puppy) when something is going on outside and she
gets excited and then tries to chase and grab one or the other of
the cats... she has very strong jaws and I am afraid that someday
she may actually bite one of them.  Would some sort of prozac
type drug help her?
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Followup To

Question -
I own 4 dogs and three cats.  My older dog, Mia, is half chow
and half shar-pei.  She has always been a gentle dog, but lately
she has started trying to attack our cats.  She is 12 1/2 years old
and recently had surgery to remove a skin tumor on her bottom
that was found to be malignant.  They think they have gotten the
cancer cells.  She has not shown any symptoms of illness and
healed quickly after the surgery.  My question is would starting
her on some sort of medication for mood help?  I am very afraid
she may hurt one of the cats.  Thanks for your help.

Answer -
Leslie, could you detail a little more her behavior towards the
cats? When does she try to attack them, and exactly what does
she do?? It could be due to age (perhaps she's losing her
eyesight and they are startling her), or there might be another
underlying health problem. Have you always had the cats? Have
you noticed them tormenting or annoying her?

Kristen

Answer
Mia's behavior sounds a little like 'displaced aggression.'

"Displacement behavior occurs when a dog is prohibited from performing a task or behavior that it want to perform. The dog lets out its frustration by pouring that energy into a different behavior which is many cases is somehow associated with the original behavior that cannot be carried out.

For example, in displaced aggression, a dog that has is prevented from fighting with another dog may sometimes bite its owner's hand. Although the dog would otherwsie never do this, by stopping the dog fight, the owner has prevented one behavior, and the dog has to "take it out" on someone, so it snaps at the owner. The reaction is reflexive and not intentional. At the time it bites its owner, it has no idea it is doing so. (http://doglinks.co.nz/)"


This is something that's very difficult to provide suggestions for over the internet. My best advice is to contact local trainers that have experience dealing with aggression, and who can come to your house to help you work with her to stop the behavior. You are right in that she could very easily injure or kill the cats. Since she only shows the behavior when she is stimulated by something she sees outside, I do not think that putting her on medication is the answer.

Kristen