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Why is my vaccinated puppy vomiting, bloody diarrhea, and lethargic?

Updated On September 23rd, 2025

Pet's info: Dog | Chihuahua | Male | unneutered | 4 months and 23 days old | 8 lbs

My dog has had 3 Vaccinations but he won't eat all he does is lay around any was vomiting and he had a bunch of bloody diarrhea one time but he is alert and drinking lots of water what is wrong with him please help

1 Answer

Most Helpful Answer

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Answered By Dr. Dayna, DVM, CVA

Veterinarian, Certified Veterinary Acupuncturist

Published on October 24th, 2017

What you describe is very concerning. Puppies can become dehydrated quickly when there is vomiting and diarrhea. The blood increases my concerns as well. Even though he has been vaccinated, parvovirus is still a concern for Tanner. I would highly encourage you to have him seen by your veterinarian as soon as possible. Please take a fresh poop sample with you when you go to the veterinarian, as certain parasites can cause those symptoms as well. Best of luck and I hope he improves soon.

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