Dogs literally drool with excitement

- Ms. C, Peoria

Dear Ms. C: There are several reasons why dogs drool. I suspect Mac simply drools because of excitement. As a matter of fact, the only way I can tell that Afghan hounds are excited is when I see them drooling. No tail wagging, no barking, no panting, just drooling.

There is a complex physiological reason that some dogs drool when excited, which is related to the nervous system, in much the same way that humans produce more saliva at times when they think of food. Different strokes for different folks, I guess. Dogs like St. Bernards that produce copious amounts of saliva often drool because they have lip shapes that are loose and fold over in such a way that saliva simply runs down the side of their face. They don't produce excess saliva; they just can't keep it in their mouths. Mac could have a similar problem.

It sounds as if Mac's drooling, medically termed hypersalivation or ptyalism, is not a constant occurrence. I suspect that anything that makes him excited will increase his salivary flow. Such stimulation may involve being around other dogs in the show ring or being around strangers.

Interestingly, drooling in some dogs is associated with a serious medical problem called a hepatic shunt, which is due to extra blood vessels which shunt blood around the liver rather than through it. Surgery is the only cure. I'm not sure anyone knows why there is a connection between the shunt and drooling, but it would be a problem I would be more apt to look for if Mac drooled constantly.

Another interesting theory is that some dogs who drool may have a mild form of epilepsy, called limbic epilepsy, which can stimulate salivary glands to produce more secretions. Phenobarbital, or some other anti-convulsant, usually is the solution for that.

Nausea also can stimulate drooling. A dog that has never been known to drool before but is noticed drooling suddenly may have nausea as the inciting cause. Of course, it is wise to check a pet's mouth to make sure he hasn't picked up a stick or other object that might be lodged between his teeth. I saw a golden retriever once who had a toothpick lodged in the back of his throat.

Another cause of drooling, which of course doesn't fit Mac, is due to a pet having a bad taste in his mouth. Dogs that pick up toads or frogs are especially likely to develop hypersalivaton - probably due to taste. There is even a medical condition in dogs termed toad poisoning that is caused by a particular species of toads.

In Mac's case, since excitement is most likely setting off the drooling, you might be better off to treat him with a safe drug each time you know he is going to be shown. A drug similar to atropine can be administered before he is shown. Atropine decreases salivary secretions immediately. It is also possible that as he becomes more comfortable at dog shows, he will be less likely to drool.

Perhaps the only real consolation I can offer is that you don't have a giant breed with this problem.

Speaking for Alex this week is Dr. Larry Baker, who practices small animal medicine and veterinary dentistry at 2800 N. Martin Luther King Jr. Drive in Decatur. To submit a question, write to Ask Alex, c/o Herald & Review, Box 311, Decatur, IL 62625 or e-mail jmatherly@herald-review.com.