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Why isn't my outdoor cat gaining weight? Could it be parasites?

Updated On September 23rd, 2025

Pet's info: Cat | Domestic Shorthair | Male | unneutered | 3 months and 19 days old | 0.44 lbs

So my cat eats normally and every morning has a vitamin pill (Ecuvit Feline) but he doesn't gain any weight. Could he have parasites and how am I supposed to know? He is an outdoor cat. What could cause this?Thanks!

1 Answer

Most Helpful Answer

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Answered By Jenna Beyer, DVM, MBA, cVMA

Veterinarian, Certified Veterinary Acupuncturist

Published on August 8th, 2017

Outdoor kittens will commonly have intestinal parasites. You can try an over the counter pet dewormer, but there are a few intestinal parasites that need to be diagnosed by a veterinarian so a prescription medication can be used (like coccidia and giardia). Also, make sure you are feeding enough and that other cats aren't eating the kitten's food. It is possible that there is other illness causing vomiting or diarrhea that you don't see since he is outdoors, including inflammatory bowel disease, bacterial or viral gastroenteritis (like panleukopenia), congenital disease, among others. I recommend that Felix see a vet for examination to determine if additional testing is needed.

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