When a dog vomits water and is accompanied by foaming at the mouth, it cannot be ruled out that it is organophosphorus poisoning. It is usually accompanied by incontinence of urine and feces, twitching of limbs, and various abnormal neurological symptoms. It is recommended to send the dog to a pet hospital for treatment in time to prevent the dog from being poisoned and dying. During this period, you can feed the dog an appropriate amount of drinking water to help replenish water and speed up the metabolism in the body.
This may also happen if a dog accidentally eats a foreign object. The foreign object stuck in the dog's throat or esophagus needs to be removed. If the foreign object is deep in position, the dog needs to be taken to the pet hospital for removal.
If the dog foams at the mouth and vomits translucent liquid, it means that the dog has a gastrointestinal problem, the gastric mucosa is damaged or there is excess gastric acid. It is necessary to adjust the diet or give the dog a check-up, and then prescribe the right medicine.
Canine distemper and parvovirus can also cause dogs to vomit white foam, which mostly occurs in dogs that have not been vaccinated. The vomiting of mucus is usually accompanied by runny nose, fever, diarrhea, etc. Therefore, if your dog vomits mucus due to a disease, you should take your dog to the hospital for examination as soon as possible to see what kind of disease is causing it and treat it accordingly.

Such as meningitis, parasitic infection, epilepsy, etc., can also cause symptoms of dogs vomiting foam, and require medical examination before definite treatment.