Bulldogs World

I would definitely think it is connected with your ant invasion. 

I had a cocker spaniel years ago. She was outside one day when she came running frantically toward me, only to run smack into the curb of the sidewalk we were near. She flopped around a bit, foaming at the mouth. I was about 13 at the time and totally freaked out! I ran home carrying her, but by the time I got there she seemed some better. She drank a lot, then was lethargic all that day. The next day she was fine. It happened again at my dad's house, my little dog was on his back patio when suddenly she came running through the house and ran head first into the front door. Foaming at the mouth, convulsing. Then she was ok, but lethargic. The only connection to the two incidents was that she had licked up an ant right before it happened each time.

I feel for you, it isn't fun having them invade a home.

either from pain or nausea unless he has an ant stashed somewhere in his mouth or got bit by one (pain).  Be very careful with the extermination, make sure they know there is a dog on the premises.  Our bug guy always uses killers that won't harm the dogs and puts ant bait up high enough that they can't reach it.

I can tell you from almost 11 years experience with my bullie that it is almost ALWAYS related to nausea when he drools excessively. And with him, it's usually related to an oncoming ear infection. I've told the Vet several times that of all the things we've ran in to with him in his long life, the periods of heavy drooling are the worst. It's not the mess I mind, it's the feeling that something is wrong but you can't figure out exactly what it is. Getting stressed over it is one of the worst things you can do though. It just stresses him out. Just stay calm, give him a GasX (in case it is nausea), and realize that he will stop doing it on his own (usually overnight with mine).