The three year old German shepherd had been agitated a bit, and his owners decided to bring the dog to their local veterinarian. Finding no physical reason for the dog's behavior, the vet recommended a short course of Acepromazine. "Ace" is a frequently used drug to calm a dog that's fearful of thunderstorms. It's also used as a pre-operative sedative, and for a multitude of other uses, all of them valid. I've used it on thunder-phobic shepherds over the past decades and never had a problem with it. And it's one of those drugs that I keep around just in case I need it.

The owners took the dog home. In the coming days they saw a marked increase in aggression, directed toward them. When the dog finally turned and tried to bite the husband, it signaled the end.

We don't know, of course, what caused the dog's initial agitation. But most likely the marked increase in his level of agitation after having been given Acepromazine may well have been the result of the drug causing what's called in the veterinary world as a "paradoxical reaction"–a response that's one hundred and eighty degrees from what you'd normally expect. With Ace, you'd expect a quieter, more sedate dog. However in some cases, that's not what occurs. Instead the dog becomes even more agitated, fearful, or aggressive. The problem is that few vets have access to all the information being compiled on the panoply of drugs out there today.

Shalimar, who passed away last October, was deathly afraid of thunderstorms, so I gave her Ace whenever a storm was approaching (Ace takes 15-25 minutes to take effect). Usually a dog Shali's size is dosed around 15 mg of Ace. However if you gave her 15 mg, she was not only "sedated", she couldn't walk hours later. Obviously we had to cut her dose. Finally I was taking 5 mg. pills and cutting them in half. That dose worked just fine for her and she was able to get through the spring and early summer storms that hit this area of the country without running around the house in a panic.

The interesting thing with Ace was that no matter how Shali was dosed, given the right stimulus, she'd just about shake it off. I remember her flat out of it one evening when the storms decided to veer off to the north. Just to see how she's react, I asked, "Want to go for a walk?" The words were magic. Shali leaped up and ran around the house as if she hadn't been sedated at all. Later I found out that this "punching through" the effects of the drug wasn't uncommon.

Many veterinarians are prescribing mood elevators such as Prozac, another drug that's done wonders for the canine community. Dr. Nicholas Dodman's work in this area has saved countless dogs who developed one behavior problem or another and couldn't cope with it. (See THE DOG WHO CRIED FOR HELP by Dr. Nicholas Dodman, DvM). I have my current shepherd on Buspar, a mood altering drug developed for human use, which is now being applied to dogs and cats. It's a "feel good" drug that often helps with inter-dog and inter-cat aggression and often prescribed by veterinarians. There are a number of such drugs out there and they often either clear up or mitigate behavioral problems when training and other forms of conditioning don't work. And although the pharmaceutical companies do a lot of testing, the incidents of these so-called paradoxical reactions can be so low that they don't show up in the tests.

Paradoxical reactions happen with other drugs too, so it's not just the sedatives or the mood elevators (like Prozac) where the drug can have this kind of effect. Therefore, whenever you start your best friend on a new drug, keep an eye out for abnormal behavior, which can include elevated agitation, aggression, a general "unsettledness", or anything else that's out of the norm for your dog.

Should you encounter a paradoxical reaction (or what you believe to be one), contact your veterinarian immediately. If your vet doesn't know of any incidence of paradoxical reactions, she or he can check with the major veterinary schools like Tufts University School of Veterinary Medicine in Grafton, Massachusetts.

Remember, your shepherd can't tell you what's going on inside. It's up to you to do the thinking. So be alert to changes in your dog's behavior and demeanor. And when you see something that surprises you, take a hard look at all possible causes…especially changes in your dog's diet or drug regimen.

*About the author

Richard Bajackson is not a veterinarian. However over the forty years he's been owned by German shepherds, Rick has run across enough dog-related issues to fill a large notebook. Unfortunately most of these "lessons" (for lack of a better term) are often learned the hard way in the proverbial school of "hard knocks". He has no affiliation with anyone including The Tufts University School of Veterinary Medicine or Amazon.com both of whom are mentioned in the article. When he discovered the JustShepherds web site, he knew had found the perfect vehicle to share his extensive experience with other German shepherd owners. Expect to see more from him over the ensuing months.