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My cat had diarrhea, now no poop after Flagyl. When should I worry?

Updated On September 23rd, 2025

Pet's info: Cat | American Shorthair | Male | neutered | 14 lbs

took my cat to the vet on Thursday evening for severe diarrhea. They gave him fluids, probiotics, and prescribed flagyl. He had one poop late at night between thurs and Friday and it was diarrhea Since then he has not pooped at all- no straining or even trying. He's acting completely normal and eating and drinking and peeing. Not sure when to be worried, we've been back and forth to the vet lately a lot for Crystals and other bladder things (he had been off of all meds for 2 weeks at time)

1 Answer

Most Helpful Answer

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Answered By David Elbeze, DVM, MRCVS

Veterinarian

Published on December 25th, 2016

You should not be worried yet, after several days of diarrhea, the intestines empty completely and it takes 2-4 days to start and having stools again, as long as he is otherwise back to normal that's the most important thing. Flagyl also tends to cause slight constipation, but again nothing to be worried about just yet.

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