In hot weather in summer, saliva tends to stick to the mouth

Basically, in this season, it is not a big problem for dogs to foam at the mouth after a little exercise. If there is only foam hanging around the mouth and there is no listlessness or vomiting or other symptoms, it may be because the weather is hot and the dog is active, resulting in a large amount of saliva and accumulation on both sides of the mouth. Dogs do not have sweat glands and can only use their tongues to perspire. In hot summer, dogs exercising outdoors will secrete a large amount of saliva and use evaporation to take away heat. Therefore, the amount of saliva will be particularly large, and mouth problems will occur easily. There is foam on the sides.
Just wipe the saliva from your mouth and feed your dog water.

Dogs will also have foam at their mouths when they are hungry

Dogs are relatively hungry animals, but after they have been hungry for a period of time, because Because the dog needs to eat, it will start to secrete saliva in preparation for eating. If there is saliva around the mouth and you have not eaten for a while, you may vomit. At this time, the vomitus will also be white.
If you find your dog drooling, wandering around you uneasily, or jumping on you, biting your trouser legs or hands, it may be that your dog is hungry.

Male dogs will also drool when they smell the estrus secretions

When male dogs smell the estrus secretions of other female dogs, they will also have foam at the corners of their mouths. situation occurs, but this situation depends on the breed of the dog. Or if you smell a puddle of urine outdoors or smell another dog's butt directly, the foam at the corner of your mouth may also be due to the hot weather.