Q I have a 12-year-old Papillon who will occasionally have what I am told is reverse sneezing. I understand that this condition is not supposed to be serious, but it seems when it happens, it wears him out. Can you tell me what causes this and any way to treat it? He is already on Benadryl twice a day for allergies.

A: Reverse sneezing is one of those unusual sounding - both in name and in the way it actually sounds when your dog is doing it - things dogs will do that people do not.

Since dogs do not blow their noses as we do, they will do what has been termed a reverse sneeze in an attempt to clear their nasal passages. This is when they forcibly inhale air through their nostrils with their mouth closed.

When occurring it sounds terrible and it looks as if they are having trouble breathing. We have had patients rushed in with the concern that the dog is suffocating.

The main thing to watch for is their mouth. With a reverse sneeze, it will be closed, while with a problem breathing, it will be open. They keep their mouths closed to suck air in and hopefully suck out anything lodged in their nose.

This can be a hard event for an owner to describe. Just last week, a 9-year-old neutered male Boykin came to me to recheck what his owner described as a chronic cough. Based on his description of what he was doing two times previously, we had performed bronchoscopy (where we look down the trachea) and a tracheal wash (where we collect mucous from the airway) to try and determine why he was coughing.

Treatments based on these tests were not helping. These procedures require anesthesia and are not inexpensive.

During the visit, I (Dr. Perry Jameson) tried to get a thorough history as to what was going on. His dad described how he would cough when first getting up and only occasionally during the day, usually after lying still. He was still active and able to retrieve when they went hunting.

I had decided that since the symptoms were so mild and we were obviously not getting an answer to hold off repeating the tests a third time. As I walked them to the reception area, he did a quick reverse sneeze.

"There he goes coughing again when he gets moving," he stated. I asked him if that was what he was doing at home and he said, yes, that little cough. I explained to him that he was actually having a reverse sneeze and not a cough and that this would be associated with nasal disease not lung disease as a cough would.

Through no fault of his or ours, we had been looking in the wrong place!

I almost stuck with my original plan which was to recheck in 30 days, but he had fasted him just in case anesthesia was necessary. As they were walking out the door, I grabbed them and told him why don't we take a quick look in his nasal passage. He agreed and we took a look with an endoscope. There just above his soft palate was part of a pine cone. With all the snorting, he had wedged it in place and it took about 30 minutes and two veterinarians to pull it out.

So the first thing to getting an answer to reverse sneezing, or for any problem, is to have a detailed description of what is actually happening. Note if the mouth is open or closed when occurring. Are they breathing in or out during the event?

These and other details help us isolate the problem and plan appropriate testing. A video of the event may help, too, so we can actually observe what is happening.

Diagnosing the cause of reverse sneezing is not always as easy as it was in this case. A dog's nose is a complex structure with hundreds of folds of tissue called turbinates that the endoscope cannot get into. Also, dog sinuses are rarely accessible with an endoscope and disease can hide there. A CT scan is another way to image these areas and is often done in conjunction with the scoping.

Foreign bodies are only one possible cause for reverse sneezing. As dogs age, tumors are the most common cause for nasal related symptoms. Aspergillosis, a fungus, can grow in the sinus cavities of dogs. Tooth root abscesses may erupt into the nasal passages, causing reverse sneezing.

It appears rare for dogs to develop symptoms secondary to allergies as humans do and the reason most will not respond to antihistamines. That being said, I have one patient who the allergist and I feel is allergic to the cats in his home. Every time he stays at the kennel, his symptoms go away. A small percentage of dogs will have inflammation (rhinitis) with no obvious cause.

As with any problem, the only way to know how to treat is to get an answer as to what is causing the symptoms in the first place. Reverse sneezing is rarely an emergency but usually sign of nasal disease that should be checked out.

Dr. Henri Bianucci and Dr. Perry Jameson are with Veterinary Specialty Care LLC. Send questions to petdocs@postandcourier.com or veterinaryspecialtycare.com.