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My dog is on Prozac for anxiety. Why is he losing his appetite?

Updated on September 23rd, 2025

Pet's info: Dog | Catahoula Leopard Dog | Male | neutered | 3 years and 2 months old

Recently prescribed Prozac 30mg daily for anxiety, currently day ten but experiencing loss of appetite, is temporary? Been adding wet/broth to kibble.

5 Answers

Most Helpful Answer

Answered By Christie Long, DVM

Veterinarian, Certified Veterinary Acupuncturist

Published on April 21st, 2016

In my experience the decrease in appetite associated with starting Prozac usually resolves in 3 - 5 days. Making the food extra tasty, as Dr. Elbeze has suggested, is a great idea. If the appetite loss continues after 5 days, talk with your vet about a temporary decrease in the dosage (often we'll halve the dose to see if the appetite comes back) and then gradually work back up to a full dose again.

9Pet Parents found this answer helpful

Related Answers from Veterinarians

Answered By Lindsey Edwards MVB, BSc, IVCA
Veterinarian
Inappetance would not be a recommended side effect, I recommend discussing the development of such signs with the prescribing vet who may recommend blood tests to investigate other internal causes and possible discontinuing of medication. Do not alter any prescription medications except on advice of the prescribing vet familiar with your pets individual history and clinical status
0Pet Parents found this answer helpful
Answered By David Elbeze, DVM, MRCVS
Veterinarian
Loss of appetite is the most common side effect of this medication and it is usually temporary. try adding some wet dog food and see if it helps a little.
2Pet Parents found this answer helpful
Answered By Dr. Melanie, BVSc MS
Veterinarian
Published on October 15th, 2018
Loss of appetite can be a sign effect of Prozac in dogs. It is a normal side effect. Continue to try to tempt Phoebe to eat, even offering her some boiled white meat chicken (no bones) and rice. I hope this helps!
1Pet Parents found this answer helpful
Answered By Jennifer Summerfield, DVM CPDT-KA
Veterinarian, Certified Dog Trainer
Published on October 1st, 2018
Hi there. It sounds like either the medication, or the food itself may be making him feel nauseous. It's common for dogs to act more aggressive when they don't feel well. I would recommend talking with your veterinarian about this issue to see what they suggest.

You may need to experiment with giving his meds at a different time, to help determine if it's the medication or the food itself that is making him feel sick. If it's the medication, you and your veterinarian could discuss switching to a different SSRI such as paroxetine or sertraline to see if he does better with this. If it's the food itself, then a diet trial with a prescription GI food or further work-up for an underlying GI issue may be helpful.
1Pet Parents found this answer helpful

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How long are dog anxiety meds stable in pre-made meat treats?

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