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My dog is weak, lethargic, vomiting, not drinking, and eating less. What's wrong?

Updated On September 23rd, 2025

Pet's info: Dog | Saint Bernard | Female | unspayed | 8 months and 4 days old | 9.9 lbs

It's summer and my dogs seems weak and lethargic. Ali sometimes vomits but still eats a lot, while Kai is only eating small amount of food that's way too different from her original meal and is not drinking water. I'm getting worried. What should I do? What do you think is wrong with them?

1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on April 12th, 2018

I would get both Ali and Kai checked out by a vet as soon as possible. In summer, it's very important for dogs to drink a lot of water to stay cool, and it's concerning that Kai isn't drinking water. It's also concerning that Ali is vomiting. Being weak and lethargic is a general sign of illness that could be caused by systemic illness, infection, inflammation, or injury, so that is why a vet visit is recommended. I'd call your vet today to set up an appointment for them as soon as possible. Best of luck!

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