Hi aobrnw -
Possible reasons for excesive drooling would include 1) dental disease 2) getting into something that tasted bad - if he picked up little toads or bite bugs when outside it can cause this. Including bee sting inside mouth - anything that has a bad taste can cause excess drooling. If you think this may have happened, it may be helpful to rinse his mouth out with water to help get the bad taste out of his mouth and then get him to eat something. 3) Eating something that was very irritating to tissues of his mouth - this would include if he licked a cleaning product or certain plants they chew on. This may cause sores on the surface fo the tongue and on the roof of the mouth. Include electrical cord chewing4) Some object stuck in their mouth, like a small piece of wood lodged between the teeth 5) Internal organ disease - kidney failure will cause sores in their mouth (usually on the inside fo the cheeks or on the surface of the gums) which can cause drooling, and certain types of liver disease can cause the drooling too (usually without causing the sores in the mouth) 6) nausea for whatever reason 7) Reaction to some flea products - have you used any flea products on him recently, let me know what they were. 8) There are some other immune type disease that can cause sores in their mouths. These are serious but not very common. 9) Any tumor type growth in the mouth There are probably a few other causes that are much less common. Have you looked in his mouth to see if you see anything abnormal? (Dogs don't always cooperate for this so be careful not to get bit.) Look to see if anything is stuck between the teeth. If you see any unusual redness or sores, that would explain the drooling, and then you just have to figure out why they are there. If there are no abnormalities in the mouth, blood work may need to be done. I have on occasion seen this and not been able to figure out a cause. We treat symptomatically (there is medication that can be given to decrease the drooling) and it usually resolves on its own. If the drooling is excessive, animals can actually become dehydrated from this.I would have him checked out by a vet if this continues. Some of the causes of this are serious and some are not, but if it doesn't go away, better to have him seen so they can check for some of the things I mentioned above.
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