Why does my cat have a musty foul smell by his bottom?

Our question this week was:

My cat just came back from the vet after being vaccinated and he stinks. His entire rear end has a musty foul smell. Why and what should I do?


William B.


Hi William– thanks for your email. You wrote that your cat went to your vet and came back with a foul musty type stinky smell.

My guess is that your cat expressed his anal glands at some point in time. The anal glands are small scent glands located on each side of the rectum. They are naturally expressed when a cat has a bowel movement. However when cats are scared – they will often fully release them (express them) which releases the content of the gland and an associated a foul musty odor. There is no odor quite like anal gland odor – it is distinctive and potent.

The fact that your cat expressed them is not a worry. It is not uncommon. I’d recommend that you try to wash his bottom (if possible). Focus on the rectal area. Use warm soapy water on a paper towel or two. Then wipe with just a plain paper towel to dry. This should take care of the majority of the odor and his grooming should take care of the rest.

An article that might be helpful to you is Anal Glands in Cats.

Best of luck!

Dr. Debra

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