HomeShelter & rescueWhat Is Trazodone, and Why Is it Given to Shelter Dogs?

What Is Trazodone, and Why Is it Given to Shelter Dogs?

The antidepressant can be a godsend to anxiety-ridden dogs, as well as to pups prone to getting sick in shelters

by Jennifer Abrams, LVT, ACAAB and Sarah Byosiere, PhD, | March 25, 2024

What Is Trazodone, and Why Is it Given to Shelter Dogs?

Cierra Voelkl / Unsplash

Gone are the days of Disney’s Lady and the Tramp, when dog catchers rounded up strays and took them to dog pounds to sit in cages. Animal shelters are increasingly staffed by caring and committed animal lovers, have welfare conferences, veterinary-shelter medicine specializations, and many even have enrichment programs.

Yet even with these improvements, animal shelters — especially large, open-admission municipal shelters — are inherently stressful places, where even well-adjusted pets can shut down physically and behaviorally. 

So what can be done to help these anxious pets? Animal Care Centers of NYC (ACC), New York City’s only open-admission animal-shelter system, began a trial of low-dose trazodone to ease their dogs’ transition into the shelter environment.

What is trazodone?

Trazodone is an antidepressant often prescribed for generalized anxiety disorders and specific phobias in dogs (for example, loud noises caused by thunderstorms). Trazodone is also used for dogs experiencing intermittent or acute anxiety. The transition into a shelter may be a similar stressor: Everything a dog was once comfortable with, and in control of, is jarringly removed. So the unexpected becomes the norm.

Is trazodone for dogs the same as for humans?

Yep, trazodone for dogs is the same drug used for humans. Trazodone has been used in human medicine since 1981, and more recently, it has been prescribed off-label for dogs. Never give your dog medication made for people without first talking with your vet. A veterinarian should always determine the dosage for dogs, based on the dog’s specific needs and condition.

How does trazodone work?

Trazodone works by impacting the levels of neurotransmitters in the brain, helping to calm and soothe your pup by increasing serotonin, which plays a key role in improving mood regulation. 

Classified as a serotonin receptor antagonist and reuptake inhibitor (SARI), trazodone affects serotonin in two ways. It blocks the brain’s serotonin receptors to prevent it from being reabsorbed too quickly, allowing it to remain active for longer periods of time.

This creates a prolonged mood-stabilizing effect that can help reduce anxiety in dogs, making stressful situations more manageable. It can then lead to a decrease in destructive stress-related behaviors, such as excessive barking, chewing, or pacing.

How long does trazodone last in dogs?

It takes about two hours for trazodone to kick in. Effects of trazodone last between eight and 12 hours in dogs who have taken a single dose, but it may stay in the system for up to 24 hours. For dogs on long-term trazodone, the effects can take longer to wear off.

Side effects of trazodone in dogs

Trazodone has few side effects. It is well-tolerated in nearly 80 percent of dogs, but any dog on trazodone should be monitored. Side effects include:

  • Sedation, drowsiness, or lethargy

  • Nausea and dizziness

  • GI issues (vomiting or diarrhea)

  • Changes in appetite (some dogs may become more hungry)

Most of the more serious side effects of trazodone occur when used in conjunction with other medications. For example, there’s an increased risk of bleeding when used with NSAIDs, and trazodone should not be combined with other serotonin-enhancing drugs.

When used in a shelter environment, pets are monitored closely to check for appetite, water intake, activity level, and signs of anxiety or stress-related behaviors.

Trazodone can help improve shelter pets’ health

In addition to environmental stress, shelter-housed pets get sick easily due to exposure to novel germs, a high viral load in the environment, stress-weakened immune systems, or a combination of all three. (Yikes.)

The first step in combating this is for shelters to meet their pets’ basic veterinary and behavioral-care needs, and put enrichment policies into place to minimize stress. But in spite of these measures, rates of contagious respiratory illness (particularly kennel cough) remain high at ACC and other shelters across the country.

ACC has full veterinary and behavior teams in each shelter to provide for the animals’ physical and mental needs. They also have an extensive enrichment program and one of the highest placement rates in the nation for a large-city municipal facility.

What else could further reduce rates of contagious illness linked to immunosuppression caused by high levels of stress? For shelters like ACC, which have made great strides in addressing overall welfare practices and direct sources of contagion, pharmacological intervention is a logical next step.

Reducing contagious illnesses with trazodone 

ACC began to use low-dose trazodone on a trial basis to ease the transition period into the shelter environment. The study results suggest that trazodone may be a useful way to reduce pets’ stress in the shelter and improve their qualities of life — by indirectly affecting their immune suppression, and possibly improving their resistance to highly contagious illnesses like kennel cough. 

In the study of 1,766 cases, they found:

  • Fewer dogs in the trazodone group (29.1 percent) were sick, compared to the no-trazodone group (41.2 percent).

  • Dogs in the trazodone group had a statistically significantly shorter length of stay (an average of 9.23 days) in the shelter, in contrast to dogs in the no-trazodone group (an average of 10.47 days).

  • Dogs in the trazodone group had a higher rate of adoption (42.1 percent), compared to the no-trazodone group (30.4 percent).

Early intervention in a shelter is critical for a pet’s success. And trazodone has proven to be a useful way to ease pets’ stress in the shelter, which has a wonderful cascading effect of minimizing their tendencies to pick up illnesses.

Giving shelter dogs the best chance

When using trazodone in a shelter situation, the goal is not to mask stress or behaviors, but rather to facilitate a smoother transition. Trazodone should be used in tandem with other non-pharmacological protocols. It’s very important that other enrichment and stress-mitigating procedures are used within the shelter (e.g., conspecific playgroups, individual socialization sessions, music, quiet lights-out time overnight, scent enrichment, and food puzzles).

In other words, this method is one of many in an arsenal of techniques that can be used — collectively, and when all other possibilities have been exhausted — to set up a dog for success in a stressful environment.

Commonly asked questions

Is trazodone safe for dogs?

Yes, trazodone is safe for dogs with minimal side effects, when used as directed by a veterinarian. It’s important to follow your vet’s instructions, and let them know of any concerns.

Is trazodone available for dogs without a vet’s prescription?

No, trazodone is not available for dogs without a vet’s prescription. Your veterinarian will review your pet’s specific needs, weight, and medical history in order to prescribe the correct dosage.

Can I use trazodone to treat separation anxiety?

Yes, trazodone can be used to treat separation anxiety in dogs in conjunction with training. Separation-anxiety training will ultimately provide your pup with the best long-term treatment.


Adverse Effects of Trazodone in Dogs on Primary Hemostasis and Electrocardiogram: A Single‐Blinded Placebo‐Controlled Crossover Study

Behavioral Pharmacology in Shelter Settings

Echocardiographic Effects of Oral Trazodone on Left Ventricular Function in Healthy Dogs

Effects of Trazodone on Behavioral and Physiological Signs of Stress in Dogs During Veterinary Visits

Effects of Trazodone on Behavioral Signs of Stress in Hospitalized Dogs 

The Use of Trazodone to Facilitate Post-Surgical Confinement in Dogs

Jennifer Abrams, LVT, ACAAB and Sarah Byosiere, PhD

Jennifer Abrams is a Behavior Consultant with Behavior Vets of NYC. She previously served as the Director of Animal Welfare at Animal Care Centers of NYC. She is a licensed veterinary technician and Associate Certified Applied Animal Behaviorist, with a master’s degree in Animal Behavior and Conservation from Hunter College. She is passionate about representing the shelter-animal population in the scientific literature on welfare and well-being.

Sarah Byosiere, PhD, is director of Thinking Dog Center at CUNY Hunter College, where she focuses on studying the behavior and cognition of domestic dogs and other canids. Her research evaluates a broad spectrum of issues, including, but not limited to, the function of the play bow, dogs’ susceptibility to visual illusions, optimal methods in dog training, and improving the lives of shelter dogs.