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Why does my new dog still have diarrhea after vet visit & diet change?

Updated On September 23rd, 2025

I got her a few days ago and she has had diarrhea since I've had her I took her to the vet and they did a fecal exam but everything was negative. The people I had bought her from had started her on pedigree and then switched her to ol Roy and when I picked her up they said they wasn't sure what food she was on now?! So I had her examined and put her on royal canin as per the veterinarian suggestion and it's been 2 days and she still has diarrhea. She had her first shots 2 days ago and wormed

4 Answers

Most Helpful Answer

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Answered By Joy Fuhrman, DVM, MBA, CPA

Veterinarian

Published on February 10th, 2017

Dogs will frequently develop diarrhea from a diet change which is why it is recommended to slowly transition your pet from one food to another. Since worms have been ruled out, it is likely that this is your pup's issue, although there may be many reasons for diarrhea including infection, allergies and other disorders. If the diarrhea does not resolve in another day or two, you should take her back to your veterinarian to determine the underlying cause of the diarrhea.

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    Answered By Ana M, DVM

    Veterinarian

    Published on November 12th, 2019

    Thank you for submitting your question regarding your puppies. I recommend going back to their original diet. They will also need to see their veterinarian for fecal testing. Diet and intestinal parasites are the most common causes of diarrhea in young puppies. Other gastrointestinal tract infections can be to blame though. This is why fecal testing is important. I hope this information helps!

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    Answered By Jenna Beyer, DVM, MBA, cVMA

    Veterinarian, Certified Veterinary Acupuncturist

    Published on September 15th, 2019

    Common causes of diarrhea in a puppy include food intolerance or allergies, intestinal parasites, dietary indiscretion, bacterial or viral infection, stress colitis, among others. I would recommend having Luna evaluated by a vet to determine what could be going on and which treatments are needed.

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    Answered By Ricardo Fernandez, DVM

    Veterinarian, Veterinary Oncology Resident

    Published on August 12th, 2019

    Thanks for using Petco Pet Education Center, formerly Petcoach! This may be due to stress from changing to a new environment. However, do not forget that this may also be due to other reasons. Diarrhea can be observed with conditions such as colitis, gastroenteritis, dietary indiscretion, intestinal parasites, among many other possibilities. If this continues, I recommend that you have Bella evaluated by your veterinarian for further assessment and treatment. They may choose to check for parasites and to start medications for diarrhea depending on the results. Good luck! Hoping for a speedy recovery!

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