During a reverse sneeze, which last a few seconds up to a minute or two, the dog is usually very still with the head and neck extended. The inhalation of air can be quite forceful, leading some owners to rush to the emergency clinic. Once the episode is over, the dog resumes normal behavior. Smaller breeds are more prone to reverse sneezing and may have several episodes a day.
Reverse sneezing is caused by irritation to the throat, pharynx or laryngeal area. This can be from excitement, pulling on the leash, inhalant irritants (pollen, strong odors), respiratory infections, post nasal drip, or for some dogs, sudden changes in temperature -- i.e. leaving a warm house to very cold outdoor temperatures.
Reverse sneezes are self limiting and usually not treated with medication. Prolonged bouts of reverse sneezing, bloody or yellow nasal discharge, and other respiratory problems necessitate a visit to your veterinarian as soon as possible.