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Cat has diarrhea after new food. How long until she adjusts?

Updated On September 23rd, 2025

Pet's info: Cat | Domestic Shorthair | Female | spayed | 9 years and 3 months old | 9 lbs

Hi! Started transitioning from Merrick Turku limited Ingred. Canned to Kasiks L. Ingred turkey . On the 4th day started 50%new food and she got diarrhea ( first pic). Took her back to 25% new food and has been for 6 days now. 2nd and 3rd stool pics are from the past couple of days . Do you think it's getting better ? Planning on starting 50:50 for a week, tomorrow . How long should I give her to adjust after switching to know if it's agreeing with her system ? thank you !

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1 Answer

Most Helpful Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on April 16th, 2018

Her stool in the 2nd and 3rd pictures still look a little soft, so I would give it another couple of days on the 25%/75% mixture before going to 50/50. If when you do make that switch to 50/50 and she starts having diarrhea again, then I would say that this food isn't agreeing with her and keep her on her old food instead. I say that because if you've tried the 50/50 mixture, got diarrhea, went back a step for a bit before returning to 50/50 and still get the same result, then it's not a food that agrees with Kitty. Best of luck, I hope this helps!

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