Profuse vomiting is most definitely an emergency, particularly when associated with inability to keep down water, blood in the vomit, depression or pain
This is very dangerous for any dog but especially when it comes to puppies or small dogs.
With profuse vomiting, both the underlying cause and the vomiting itself can be a real danger.Prolonged profuse vomiting can lead to dehydration and electrolyte abnormalities, both of which can lead to further complications.
As for the underlying cause, the rule of thumb is that the more violent the vomiting, the more serious the problem causing it. You can be looking at anything starting with poisoning, foreign body, pancreatitis, severe infection or inflammation, liver or kidney failure ...
Neither of the above are things I'd want to take my chances with.
Symptoms to Watch for in Your Dog: Vomiting
Dog Medical Emergencies Survey
Dog Medical Emergencies Survey Results
Is Unproductive Retching an Emergency?
Is Difficulty Breathing an Emergency?
Is Panting an Emergency?
Is Severe Pain an Emergency?
Is Limping an Emergency?
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