What is a reverse sneeze? Dogs have a condition we call a ‘reverse sneeze.’ It gets its name because the dog rapidly pulls air into his nose, whereas in a ‘regular’ sneeze, the air is rapidly pushed out through the nose. 

If you witness a dog having a reverse sneeze it may seem alarming, but it is not a harmful condition, and there are no ill effects. The dog is completely normal before and after the episode. During a reverse sneeze, the dog will make rapid and long inspirations, stand still, and extend his head. A loud snorting sound is produced, which may make you think the dog has something caught in his nose.

A reverse sneezing episode can last for several seconds to a minute. 

The cause of a reverse sneeze is unknown. Holly Frisby, DVM, MS
Veterinary & Aquatic Services Department, Drs. Foster & Smith, Inc.