Mirtazapine Compounded Oral Liquid for Dogs and Cats

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Mirtazapine Compounded Oral Liquid for Dogs and Cats

Regular price $60.00 Save $-60.00

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This item requires prescription approval. Details

We DO NOT ship Prescriptions to the following states: Oklahoma, Arkansas, Louisiana, Mississippi, Alabama, Maryland, Washington DC, Georgia, South Carolina, North Carolina, New Hampshire, Maine, Nevada. We DO NOT ship compounds to the following state: Washington.
DO NOT place an order if you plan to ship to the states listed, if you do your order will be canceled automatically.


Help Your Pet Stay Healthy, Eat Well and Feel Good! Mirtazapine Compounded Oral Liquid Is Specially Made to Provide:
  • Treatment for animals that refuse to eat
  • Helps treat depression in cats and dogs
  • Precise dose made just for your pet’s needs
  • No additives – just the medication and a plant-based filler
  • Hypoallergenic formulation
  • Liquid formula easy to swallow for dogs and cats

Is your pet feeling under the weather or refusing to eat? Are they experiencing long-term nausea or vomiting? Mirtazapine is an appetite stimulant used to help dogs and cats that are not eating enough or are underweight. It’s also an antidepressant medication prescribed by veterinarians to treat a variety of conditions including anxiety, sleep disturbance, behavioral problems, and loss of appetite.
Mirtazapine increases norepinephrine and serotonin in the brain making it helpful in treating depression. It has anti-nausea properties and can create appetite stimulation for your pet. This medication works fast and within several days some improvement can be noticed.
Mirtazapine helps maintain a regular appetite and healthy weight for your pet with a gradual increase in energy levels. Treat your pet’s depression, nausea or vomiting with our veterinary strength formula for dogs and cats. Our easy to give compounded formula can help them feel better and have an improved quality of life. All our medications are made in our state-of-the-art pharmacy lab in Arizona, USA.
Purchasing affordable pet medications online has never been easier! ExpressVet offers the largest selection of pet medications on planet earth. If you can't find it here, let us know and we'll get it for you! Transform your pet's life with the best pet medications available on the market today.
When it comes to something as important as your pets, you want the best medication possible without breaking the bank. When you buy ExpressVet's compounded medications, you get better value and happy pets!


Mirtazapine Compounded Oral Liquid is given by mouth in liquid form once daily. This medication must be measured carefully, and it's best to use the syringe provided to ensure you are able to give the proper dosage required. After dosing your pet, rinse and dry the syringe, and screw the cap tightly onto the bottle.
If you have difficulty giving it to your pet, contact your veterinarian for some helpful tips. We recommend washing your hands with soap and water after handling any medication.
After 2 weeks of taking the medication noticeable changes can be seen in your pets weight gain and behavior.

Possible Side Effects

Mirtazapine Compounded Oral Liquid is safe for dogs and cats when taken the appropriate prescribed dosages. Side effects can include sedation, drowsiness, vocalization, low blood pressure, and elevated liver enzymes in cats.
Allergic reactions can include difficulty breathing, hives, swollen lips, tongue, or face.
If these symptoms continue, contact your veterinarian as the dosage may need to be adjusted. We recommend consulting with your veterinarian with any questions or concerns.

Drug & Food Interactions

Drug Interactions: If your pet is on any of the following medications you should use mirtazapine with caution:

  • Benzodiazepines - (eg, diazepam, midazolam): Used together may cause additive impairment of motor skills.
  • Cns depressants – (eg, antihistamines, opioids): When combined with mirtazapine may increase risk for sedation or depression.
  • Warfarin – When combined with mirtazapine may prolong prothrombin time (PT).

The following medications when combined with mirtazapine may increase risk for serotonin syndrome.
Buprenorphine, Butorphanol, Cimetidine, Clonidine, Cyproheptadine, Erythromycin, Ketoconazole, Monoamine oxidase inhibitors, serotonergic agents, selective serotonin reuptake inhibitors, tricyclic antidepressants, Tramadol

Mirtazapine should not be given to pets that are allergic or hypersensitive to it. If your pet is taking other medications, pregnant or lactating, mirtazapine should be used with caution.
Stopping the medication abruptly is not recommended since it is an antidepressant. Your pet should slowly be weaned off over a set time, which your veterinarian can assist with.


Your veterinarian will monitor your pet by measuring their increased appetite, weight gain and decreased vomiting. In cats their liver enzymes will be reviewed and monitored.

Active Ingredients



Mirtazapine Compounded Oral Liquid is given to your pet by mouth with or without food daily as prescribed by your veterinarian. If your pet vomits after receiving the medication on an empty stomach, give the next dose with a treat or meal. If the vomiting continues, contact your veterinarian.

Storage Instructions

Mirtazapine Compounded Oral Liquid should be stored at room temperatures from 68° - 77°F and away from light, moisture, heat, or humidity.


Mirtazapine dosage for dogs and cats should be given orally once daily with or without food. The exact dosage will be prescribed by your veterinarian and can vary depending on your pets’ body weight.

What if I miss giving my pet a dose? If you miss a dose, give the next dose as soon as possible. If it is almost time for the following dose, then continue with the next scheduled one and skip the missed dose. Do not give a double dose to catch up or make up for a missed dose.


What is mirtazapine?

Mirtazapine is an antidepressant and used in humans and some small animals.

Does mirtazapine cause weight gain?

Mirtazapine can be used as an appetite stimulant for weight gain. It can improve nutrient tolerance, anxiety, quality of life, and early satiation helping give your pet the ability to eat a full meal.

How does mirtazapine work?

Mirtazapine works in the central nervous system and makes certain chemicals in the brain stronger. It is available in tablets or compounded liquid for easy dosing to your pet.

How long does it take for mirtazapine to work?

Mirtazapine starts to work within the first two weeks, with gradual improvement over the following weeks. Overall, it can take 4-6 weeks to get the full benefits of the medication.

What are the side effects of mirtazapine in dogs?

Several common side effects in dogs are sedation, low blood pressure, a faster heart rate, and drowsiness. If you notice breathing difficulties, hives or swelling in the face this can be signs of an allergic reaction and you should contact your veterinarian.

Mirtazapine vs Lexapro?

Mirtazapine is the generic medication for Remeron. Both Remeron and Lexapro are antidepressants used to treat depression and belong to different drug classes. Remeron is also used to treat anxiety, nausea, and post traumatic stress.

Mirtazapine vs Trintellix?

Remeron (mirtazapine) helps improve mood and sleep better, it can cause more weight gain than other antidepressants. Trintellix (vortioxetine) can cause more nausea than other antidepressants similar to it.

Is mirtazapine safe for dogs?

Mirtazapine is safe for animals, however, should not be given to pets that are allergic or hypersensitive to it.

What is mirtazapine used for in cats?

Mirtazapine is prescribed to cats to treat vomiting, nausea, and loss of appetite. It is also used as an antidepressant.

Do I need a prescription for mirtazapine?

Mirtazapine is available by prescription only in the United States, your veterinarian will provide the appropriate dosage and prescription for your pet.

What if my pet overdoses?

If you know or suspect that your pet experienced an overdose, call veterinary services immediately. Signs of an overdose can include panting, vomiting, tremors, vocalization and increased heart rate.

What is compounding?

Compounding is a method of preparing individualized prescription medications by licensed pharmacists. Compounding allows the practitioner, the pharmacist, and the pet owner to collaborate to create custom dosages, flavors, and dosage forms for pets to easily, safely, and effectively take their medication. Often pet owners struggle to give oral tablets which is why ExpressVet offers compounded oral liquids, transdermal gels, capsules, and treats to make taking care of your pet easy.

How do I order a compounded prescription medication for my pet?

  1. Sign in to your existing ExpressVet account, or create a new account.
  2. Select the item or item(s) you are requesting and add to your cart
  3. Add your pet’s information and your vet’s information.
  4. If you are a returning customer, you will see your previous choices available or you can add as new.
  5. Let us know if you want us to request a prescription from your veterinarian, or if you would like to mail in a prescription.
  6. Complete your billing, shipping, and payment information at checkout to complete your order.

Do all compounded medications require a prescription?

Yes, all compounded medications require a prescription. Express Vet Pharmacy is happy to request a prescription order from your veterinarian, but all prescription orders must be accompanied by a patient-specific prescription from a licensed veterinarian before an order can be shipped out.

Where is Express Vet licensed to dispense veterinary prescription medications?

We are licensed in 38 states. Alaska (AK), Arizona (AZ), California (CA), Colorado (CO), Connecticut (CT), Delaware (DE), Florida (FL), Hawaii (HI), Illinois (IL), Iowa (IA), Kansas (KS), Kentucky (KY), Massachusetts (MA) ,Michigan (MI), Minnesota (MN), Missouri (MO), Montana (MT), Nebraska (NE), Nevada (NV), New Jersey (NJ), New Mexico (NM), New York (NY), North Dakota (ND), Ohio (OH), Oregon (OR), Pennsylvania (PA), Rhode Island (RI), South Dakota (SD), Tennessee (TN), Texas (TX), Utah (UT), Vermont (VT), Virginia (VA), Washington (WA), West Virginia (WV), and Wisconsin (WI)

Where does ExpressVet source the ingredients for compounding?

All ingredients for compounding are from FDA registered manufacturers and distributors.

How long does it take to process my prescription after the pharmacy receives it?

Once the pharmacy receives authorization to dispense from your veterinarian, compounded medications are prepared and shipped out within 1 to 2 business days.