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Why isn't my cat eating his kidney food even with an appetite stimulant?

Updated on September 23rd, 2025

Pet's info: Cat | Domestic Shorthair | Male | neutered | 18 years and 9 months old | 9.5 lbs

Hi tony started taking an 1/8 mirtazapine appetite stimulant every 48hrs on sept 30th to help him eat his kidney food. It hasn’t helped much.. I’m still mixing kidney with his senior food and he is still being very picky. My vet told me start giving him less mirtazapine, every 72 hrs instead of every 48 hrs. Is it common for an appetite stimulant to not help? I expected him to be so hungry that he wouldn’t be so picky about the food. any advice? Should I even bother with the appetite stimulant?

4 Answers

Most Helpful Answer

Answered By Ricardo Fernandez, DVM

Veterinarian, Veterinary Oncology Resident

Published on October 29th, 2018

Thanks for using Petco Pet Education Center, formerly Petcoach! Appetite stimulants sometimes do not help so it is not uncommon to be in this spot especially if there is significant underlying disease. I would recommend you contact your veterinarian who knows the entire medical history to make further recommendations. There are other appetite stimulants that can be tried such as Entyce. Good luck and have a great day!

1Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Jenna Beyer, DVM, MBA, cVMA
Veterinarian, Certified Veterinary Acupuncturist
Published on September 27th, 2018
Most appetite stimulants are ok with those medications, but I would have your vet double check for any drug interactions. If you get the medications from a human pharmacy, the pharmacist can also check for interactions. Appetite stimulants are safe even if the appetite is just coming back. They can be discontinued once the appetite is fully back.
1Pet Parents found this answer helpful
Answered By Dr. Strydom, DVM
Veterinarian
Published on September 23rd, 2018
Not really. The appetite stimulants are only used intermittently until the cat is eating well on their own. They don't have many side effects.

There are multiple companies that make a prescription kidney diet. You should pick one and try it. If Tony doesn't like it, you can always try a different one. I personally like Royal Canin diets but Hill's kidney diet is also great. Purina also has a veterinary prescription line. All have dry and canned versions. I prefer the canned diets for cats with kidney disease due to the high water content.

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I agree with your vet. These prescription diets are very helpful with early kidney disease.

I hope this helps. Please post again if you have more questions.
1Pet Parents found this answer helpful
Answered By Laura Johnson VMD
Veterinarian
Published on October 10th, 2018
Hi, thanks for using Petco Pet Education Center, formerly Petcoach!

I would mix his old food in with the kidney food. Go slow with the transition, over several weeks. There are also other companies that make prescription kidney food. He may like one of those better. Don't get discouraged, keep trying!

Good luck!
1Pet Parents found this answer helpful

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