Mirtazapine
Why has my veterinarian prescribed this medication?
Your pet has been prescribed mirtazapine, an antidepressant that is used for appetite stimulation in veterinary medicine.
Adverse effects:
Mirtazapine appears to be well tolerated in both dogs and cats.
Besides the desirable side effect of appetite stimulation, other currently reported side effects in animals include: drowsiness/sedation, vocalization, increased affection in cats, hypotension, and tachycardia (all dose-dependent). Increases in liver enzymes have been reported in some cats receiving mirtazapine.
Storage and handling:
Mirtazapine tablets should be stored at 25°C (77°F) with excursions permitted to 15-30°C (59-86°F). Protect from light and moisture.
Please see the prescription label for dosing information and means of administration.
Always follow the label instructions. Never administer any medication unless prescribed by a veterinarian. Keep out of reach of children.
Plumb, D. C. (2015). Plumb’s Veterinary Drug Handbook, 8th edition. Accessed via Veterinary Information Network; vin.com
Extra-label drug use
Extra-label drug use, also referred to as “off-label use” refers to the use of a drug approved by Health Canada in an animal in a manner not in accordance with the label or package insert with respect to species, indication, dose, duration, and route of administration.
A drug used in an extra-label manner does not have proven safety or efficacy characteristic based on its intended use.
The availability of approved veterinary drugs for the species being treated is always considered before prescribing medication in an extra-label manner.
With the limited approved veterinary drugs, extra-label drug use often involves the use medications made for other species (including humans) in our pets.
© Copyright 2025 LifeLearn Inc. Used and/or modified with permission under license. This content written by LifeLearn Animal Health (LifeLearn Inc.) is licensed to this practice for the personal use of our clients. Any copying, printing or further distribution is prohibited without the express written consent of LifeLearn. This content does not contain all available information for any referenced medications and has not been reviewed by the FDA Center for Veterinary Medicine, or Health Canada Veterinary Drugs Directorate. This content may help answer commonly asked questions, but is not a substitute for medical advice, or a proper consultation and/or clinical examination of your pet by a veterinarian. Please contact your veterinarian if you have any questions or concerns about your pet’s health. Last updated on Nov 24, 2021.
