Tonight my boy Ernie started hacking like he was trying to get up a hairball. This continued for about 45 minutes on and off and then all of a sudden stopped. It sounded so awful and I felt so bad for him, but there wasn't anything I could do. He didn't throw anything up which I found very odd. Have any of you had the same thing happen with your cats? This isn't the first time it has happened with him, but tonight went on a lot longer than in the past.