It's not a cough...(Long, sorry)        Carter has had a few "episodes" where it sounds like his lung collapsed and he had to "cough" to re-inflate it.  I know a little about this as our yorkie/chi mix had this for years.    
The first episode happened in the middle of the night.  It sort of started like hiccups, and then progressed into his "coughing".  I took him to the vet and described what happened.  His diagnosis was either the reverse cough or possibly a collapsing trachea.  I did not agree.  When he "coughs", it comes from his lungs, not his throat.  I also have never heard of a collapsed trachea in a puppy that's only 6.5 months old.   
We agreed to do an xray prior to his sedation for neutering.  That was last week.  I felt bad for him so I let him stick his head out the window on the way to the vet.  Well...it happened again.  He started coughing.  It was almost as if he was getting too much air in his lungs.  When I got to the vet, he was still coughing.  I explained to the tech that it wasn't a "cough" persay and tried to describe the prior episode.  I also reminded her that the vet and I agreed to do an xray of his trach and lungs prior to sedation.     
A few hours later I got a call from the vet.  There was a small area at the bottom of Carter's lungs that was "questionable".  He took an xray breathing in and another breathing out.  He was not comfortable putting Carter to sleep if there was a concern with his resperations.  I agreed.  He sent him home with 2wks worth of antibiotics and 1/2 pill per day of Benadryl (adult formula).     
Well, today it happened again.  He was just laying on the couch and started another episode.  It sort of sounded like he kept taking a whole bunch of really deep breaths in a really big hurry.  Then he "coughed" and was fine.  It doesn't seem to bother him.  He's done with his course of antibiotics in two days.   
Has anyone ever heard of this happening to yorkies?  It is not just the typical reverse cough.  I KNOW it has something to do with his lungs.  Anybody???     
				__________________  ~Lexi's (and new addition, Carter's) Mom 
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