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My dog is suddenly lethargic and won't eat. When should I see a vet?

Updated On September 23rd, 2025

Pet's info: Dog | Mixed Breed | Male | neutered | 4 lbs

Chihuahua mix, approx 3 years, suddenly became lethargic. Decreased interests in eating, walking and playing which are usually highlight of his day. He skipped two meals but ate treats, not excited for a walk or playing for 36 hours as of now. No changes in diet, activities of daily living. No vomiting or diarrhea. Not taking any meds. All vaccines up to date.Normal bowel movements. He gets extremely anxious and stressed going to vet, but wondering if going to ER or vet right away is necessary.

1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on November 2nd, 2019

Poor Poco. Given that he will eat something and is having normal bowel movements, I'd keep an eye on him for now. Offer him a bland diet of boiled white meat chicken (no bones) and white rice. If he refuses to eat this, vomits it, or the lethargy continues overnight, then have him seen by a vet immediately.

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