What Is Trazodone Used for in Dogs? Everything You Need To Know

Trazodone is typically used to treat situational anxiety in pets or as a mild sedative following surgery. “In general, [it’s] a well-tolerated medication, and most vets are comfortable prescribing it,” says Kate Farmer, DVM, a veterinarian at the Animal Humane Society in Minnesota. Still, it’s natural to have questions: How long does trazodone last? What are the trazodone side effects in dogs? How much trazodone can I give my dog?

Here, expert veterinarians answer these questions and others so you can know what to expect with trazodone for dogs.

Trazodone is a SARI, or serotonin antagonist/reuptake inhibitor, and is a human antidepressant drug approved by the FDA, but not yet approved for use in animals.

The FDA allows veterinarians to prescribe and use human products containing this drug in animals in certain situations. However, it is commonly prescribed to dogs for relaxation due to behavioral disorders such as separation anxiety, or anticipatory stressors such as travel or fireworks, says Dr. Farmer. It’s thought to work by releasing serotonin (a mood-boosting hormone) in the brain to calm their nerves, she says.

Trazodone is often used as an additional medication for behavioral problems that do not adequately respond to just one medication.

Trazodone is considered a medication associated with a low risk of side effects. Just as with any veterinary medicine, trazodone can affect some dogs more so than others, so if your pup experiences extreme sedation or lethargy even with relatively small doses, trazodone might not be the right drug for them, says Dr. Farmer.

In certain circumstances, your vet may recommend a compounded formulation of trazodone. Compounded medications are not FDA-approved and are prescribed if there’s a specific reason your pet’s health can’t be managed by an FDA-approved drug. They are created by either a veterinarian or a licensed pharmacist on an individual basis to best suit a pet’s particular needs.

There’s a wide range of reasons you might discuss using trazodone for your dog with their vet, but the goal is more or less the same: to keep them calm.

Veterinarians often prescribe trazodone for recurring issues like separation anxiety or situational fears, such as thunderstorms or visits to the groomer, says Dr. Farmer.

They may also use it to keep them at ease following surgery, she adds.

Trazodone may also be used as a complement to a complete anxiety treatment plan, says Dr. Farmer. For example, if a dog has consistent, everyday anxiety, the vet may recommend an SSRI (selective serotonin reuptake inhibitor), which also boosts serotonin—but does so gradually over time. That means “they’re increasing that long-term level of serotonin as opposed to more of a situational boost,” she says. It can take as long as four to six weeks for SSRIs to reach full effect, so trazodone may be given, as needed, throughout that onboarding period, she explains.

Be aware, though, that an overdose of trazodone with other serotonin-boosting drugs could trigger a serious condition called serotonin toxicity, or serotonin syndrome.

Finally, dogs who are restless at night, such as from cognitive issues or dementia, may benefit from the relaxation provided by trazodone, says Adam Christman, DVM, MBA, chief veterinary officer for dvm360® and host of The Vet Blast Podcast.

Trazodone is generally well-tolerated in dogs, but possible mild clinical signs can occur and include:

• Nausea/vomiting
• Diarrhea
• Sedation

Less commonly you can see clinical signs including increased anxiety or agitation, aggression, or increased heart rate.

The most serious potential side effect of trazodone, though, is serotonin syndrome, “which is a reaction that occurs when brain levels of serotonin get too high,” Dr. Farmer says. This reaction is uncommon and may be related to minor medication interactions or dosing, she adds.

Serotonin syndrome may also be triggered when a dog takes more than one type of medication that boosts serotonin.

According to Dr. Farmer, the signs of serotonin syndrome include:

• Elevated heart rate
• Tremors or seizures
• Dilated pupils
• Difficulty breathing
• Elevated body temperature
• High blood pressure

If you see signs of serotonin syndrome in your pet, immediately contact your veterinarian, seek emergency veterinary care, or call an animal poison control center, like the Pet Poison Helpline® at (855) 764-7661.

What’s the appropriate dose of trazodone that will keep your pup calm and happy, while limiting unwanted trazodone side effects in dogs? As with other medications, trazodone dosage is prescribed based on your dog’s body weight.

“There’s a pretty wide dosing range for trazodone,” says Dr. Farmer. “Some dogs will respond at that low end, and some will need much higher dosing.”

You should never administer more medication than what your veterinarian prescribes during the appropriate dosing window.

Trazodone takes effect quickly, typically in about one to two hours but timing can vary, so don’t worry if your dog isn’t showing signs of relaxing within the first hour.

Technically, it can be given daily, but it’s unlikely your vet will recommend this kind of long-term use of trazodone, says Dr. Christman.

That’s partly because trazodone is typically used to manage short-term anxiety from a stressful event and because other types of drugs may be better for managing recurring anxiety in pets.

Again, you should never give your dog more than the vet-prescribed dose.

If you accidentally give too much or your pet gains access to the bottle and ingests too many pills, call your veterinarian, your local ER, or a pet poison control center such as Pet Poison Helpline at (855) 764-7661.

If your dog is having any alarming clinical signs such as seizures or trouble breathing, see a vet immediately.

Your vet may prescribe trazodone in pill form or as a liquid (when compounded), and it should always be taken orally, says Dr. Christman. You might even find the liquid form in dog-friendly flavors like chicken, liver, or beef.

If your pup isn’t a fan of taking pills (to put it mildly), try hiding it in xylitol-free peanut butter, soft dog food, cream cheese, bread, or a pill-hiding treat (like these from Milk-Bone®).

If this is the first time you’re giving your dog trazodone, you’ll also want to do a test run, says Dr. Farmer.

“We recommend they give a practice dose at home just to make sure everything’s well tolerated,” she says. Plus, “we can get an idea of how much sedation they’re getting.”

Ideally, your pup finds a “sweet spot where they’re still alert and happy, but they’re relaxed enough to be comfortable,” Dr. Farmer says.

You’ll want to give your dog trazodone about an hour or so before the scenario if it’s being prescribed for situational fears or anxieties, to ensure it’s kicked in, says Dr. Farmer.

However, if your dog doesn’t seem to be affected by the medication, or the effects don’t show up for a day or more, you may need to speak with the vet about increasing the dosage, adds Dr. Christman.

How long trazodone stays in your dog’s system will vary, and it partly depends on how quickly your dog metabolizes it, says Dr. Farmer.

For some dogs, the drug’s effects will wear off in a couple of hours, and others may experience drowsiness for the rest of the day, she says.

This is another reason it’s a good idea to, one, start with a lower dose, and two, try a practice dose to watch how your dog reacts.

Trazodone liquid medication should be stored according to the pharmacist’s instructions, and tablets should be stored at room temperature in a dry area of your home.

Can trazodone be used long-term for anxiety in dogs?

Trazodone is not the first drug of choice for dogs with chronic anxiety or similar behavioral disorders, says Dr. Christman. That’s because the medication delivers varying levels of sedation in dogs for a temporary calming effect, but this doesn’t address the underlying cause of the chronic anxiety—whether it is separation anxiety or a recurring fear like thunderstorms.

“Most importantly, we have to identify what kind of anxiety the dog is experiencing,” he says.

Due to the gradual and long-term effects of an SSRI-type drug such as fluoxetine, these may be better suited for treating daily or consistent anxiety, but your vet will be able to make a specific recommendation.

What should I do if my dog has an adverse reaction to trazodone?

If your dog experiences adverse effects such as sudden vomiting, stumbling, or extreme lethargy, stop giving the medication immediately, and consult your vet for medical advice.

While rare, if more severe complications occur, such as tremors or ataxia (loss of coordination), get your dog evaluated by an emergency vet, advises Dr. Christman.

Will trazodone make my dog sleepy?

Yes, trazodone will have a sedative effect on most dogs. Sedation or sleepiness is typically mild but can vary from pet to pet.

If your dog is severely lethargic after taking trazodone or, conversely, you notice few to no changes in their anxiousness, consult your vet about changing their dosage.

Why is my dog shaking after trazodone?

Shaking may be a sign of serotonin syndrome, a serious side effect of trazodone in dogs, says Dr. Christman. With this condition, “serotonin levels can elevate, causing symptoms like restlessness, agitation, and tremors,” he says.

If you notice a combination of these signs in your dog, or you think your dog may be shaking after trazodone and are understandably worried, call your vet ASAP.

Seizures, which can cause a dog to collapse, convulse, stiffen, drool, or even lose consciousness, may also rarely occur with trazodone.

Can you use gabapentin and trazodone together for dogs?

This is a commonly prescribed combination of drugs among veterinarians, thanks to its “augmentative sedative effects,” says Dr. Farmer.

Gabapentin is a different class of drug than trazodone in that it works on different pathways in the brain, she says. Specifically, it works on neuropathic pain pathways, but it offers some sedation as well.

So, if your pup is entering a high-stress situation like a vet visit, and an SSRI or the trazodone alone is not enough to calm them (especially if your pup is at risk of hurting themselves if not relaxed), this combination may be used.

Trazodone isn’t the only medication vets may prescribe to dogs who experience anxiety. Here are nine other common anxiety meds for dogs.

Expert input provided by Kate Farmer, DVM, a veterinarian at the Animal Humane Society in Minnesota; and Adam Christman, DVM, MBA, chief veterinary officer for dvm360, and host of The Vet Blast Podcast.

This content was medically reviewed by Chewy vets.