Updated On September 23rd, 2025
my kitty was on Mirtazipine for appetite stimulant for 5 days and taken off-how long does the medicine stay in his system? He seems very sleepy and he was eating well on it of course but now not eating as much as he should and is very finicky. I was also giving him tuna in juice and thought that may have changed his eating preference?
1 Answer
Published on January 10th, 2019
Mirtazipine usually only stays in their system for 24-72 hours dependent on how high the dose was. If he was being dosed daily it likely was a small dose and will only be effective for approximately 24-36 hours. I would talk to your vet about continuing it. If they haven’t figured it why he isn't eating, then they may recommend additional diagnostics like blood work or X-rays. If you already know then you can continue mirtazipine longer until he is feeling better. And yes, he may have developed a preference for the tuna juice. You can continue to add tha to his other food. I hope this helps.
1Pet Parents found this answer helpful
Book an appointment with the pros – our expert vets are here to help.