Yikes! Did no one respond to your question? I can't really help because I found it in a search. My Sophie did it last night and again this morning and it freaked me out. She has never done it before and she is 2 1/2 yo. I looked on youtube and saw some videos which showed me that it was indeed reverse sneezing and not something more dreadful.
Some people on there said to cover their nostrils for a bit and it appeared to help someone. It is VERY scarey to see your beloved pup doing this.
