Walk into psychiatrist Drew Ramsey’s office in Manhattan and you’ll likely be greeted by Gus, a four-year-old shih tzu. After escorting you through the waiting room, he may hop onto the ottoman and go to sleep or sit beside you on the couch.

Therapists use ‘canine assistants’ to comfort and cheer up their patients. WSJ’s Christina Tsuei sees how psychiatrist Drew Ramsey teams up with his four-year-old shih tzu Gus.

Some patients pat Gus while they talk to Dr. Ramsey. A few talk to Gus instead. And if they get emotional, Gus provides physical comfort that therapists can’t offer. “We can’t hug patients, but patients can hug Gus,” says Dr. Ramsey, who began bringing his dog to his office two years ago. Now, he says, “I think about Gus the way a cowboy thinks of his horse—he’s part of the job.”

A small but growing number of psychologists, psychiatrists, social workers and other therapists are bringing their dogs to work in their private practices, where they help calm patients down, cheer them up and offer a happy distraction with a wagging tail. The job is similar to what therapy dogs do when they visit at hospitals or nursing homes, but these “canine therapy-assistants” often work full days and get to know the patients just as well as the doctors.

Mimi Ritzen Crawford for The Wall Street Journal

New York neurologist Gayatri Devi, who specializes in memory disorders, brings Lola, shown, and Wolfie to the office.

Even some medical doctors have put their pups to work. Lacey, part golden retriever, part spaniel, entertains waiting patients at New York plastic surgeon Janis Di Pietro’s office, though she isn’t allowed in the procedure room.

Lola and Wolfie, mutts aged three and 17, put elderly patients at ease for New York neurologist Gayatri Devi, who specializes in memory disorders. “Coming to this office can be unnerving for dementia patients, but when they see a dog, it’s disarming. They feel comforted and safe,” she says.

Research shows that a few minutes of stroking a pet dog decreases cortisol, the stress hormone, in both the human and the dog. It also increases prolactin and oxytocin, hormones that govern nurturing and security, as well as serotonin and norepinephrine, neurotransmitters that boost mood. One study found that five minutes with a dog was as relaxing as a 20-minute break for hospital staffers.

“It’s chemical, not magical,” says Rebecca Johnson, who teaches a popular course in animal-human interaction at the University of Missouri and has conducted much of the research.

Michal Czerwonka for The Wall Street Journal

Child psychologist Aubrey Fine has used animals in his Claremont, Calif., practice for 30 years. Shown are his two golden retrievers, Magic and P.J.

While there are no set requirements for having an animal assistant, most dogs who work with doctors have been trained in obedience and as therapy dogs. The Delta Society offers such courses to human-and-pet pairs nationwide, as do other organizations.

Interacting with a dog can work wonders for some patients. Early in his practice, child psychologist Aubrey Fine treated a 9-year-old girl who was painfully withdrawn and refused to speak until his golden retriever, Puppy, laid her head in the girl’s lap. The girl slowly began patting Puppy, smiled and spoke to her as her astonished parents looked on.

Melinda Beck explains to Simon Constable why a growing number of therapists are incorporating dogs into their practices and why the animals are proving beneficial in treating patients.

For the past 30 years, Dr. Fine, who practices in Claremont, Calif., has used dogs and other animals to help treat children disorders such as autism, attention-deficit/hyperactive disorder and obsessive compulsive disorder. Learning to walk and interact with the pets helps the kids learn to maintain focus, eye contact and communication. “With some children, I use the dog as an external form of biofeedback,” to help them learn to regulate their behavior, says Dr. Fine, who

Mimi Ritzen Crawford for The Wall Street Journal

Psychiatrist Drew Ramsey with his fouryear-old shih tzu, Gus, in his Manhattan office.

“You never have a problem getting a child to go see Dr. Fine—they want to go,” says Velene Lima, whose daughter, Angela, now 24, has been a patient since infancy, when a brain tumor left her with multiple challenges. “She would be bouncing off the wall when she was young, but with Dr. Fine, she’d be calm. Those dogs mean everything to her.”

Some therapists report that their dogs act differently with different patients, depending on their conditions.

“I call them ‘seeing heart dogs’—because they can see into people’s hearts,” says Lois Abrams, a marriage and family therapist in Los Alamitos, Calif., who practices with her two cavalier King Charles spaniels, Duke, 11, and Romeo, eight. Duke lies on the floor next to patients with anxiety disorders and sits on the couch close to those who are depressed.

Once, Duke jumped up and sat next to a patient she hadn’t realized was depressed. “When I asked if she was, suddenly the woman poured out her heart

Sandra Barker

Sandra Barker and High Anxiety (‘Hi’ for short) visit a patient at Virginia Commonwealth University Health System.

How can dogs be that sensitive to human emotions?

Experts speculate that people give off tell-tale scents under certain physical or psychological conditions that only dogs can detect.

That acute sense of smell also enables specially trained service dogs to recognize when seizures, diabetic comas or heart attacks are imminent in humans. Some dogs can even detect the presence of cancer cells in lab specimens—much like detecting traces of contraband or explosives in luggage.

That still doesn’t explain some of the things dogs seem to intuit. Sandra Barker, director of the School of Medicine Center for Human-Animal Interaction at Virginia Commonwealth University, recalls taking a therapy dog to visit a patient who was paralyzed from the neck down. When the patient blinked “yes” to invite the dog on the bed, the dog nestled around his head. “How did that dog know that was the only part of his body that had any feeling?” Dr. Barker marvels.

Dr. Ramsey thinks their appeal is simpler. “Like Freud said about cigars, sometimes a dog in the office is just a dog in the office,” he says. “They’re just nice to have around.”

He also thinks Gus is good for his own mental health. “Much of psychiatry is about loss and depression, so when I get a break, it’s great to have him there to take for a walk.”

What do dogs get out of working with patients?

And many dogs seem happiest when they have a job to do—whether it’s herding, guarding, patrolling or engaging in supportive listening. What’s more, patients bring presents. “Gus got a Freud chew toy,” Dr. Ramsey says.

Not every dog is cut out for the health-care profession. Dogs that are highly energetic, territorial or demanding could be disruptive to a practice. Temperament is more important than any particular breed, says Dr. Barker, who says the Virginia Commonwealth program has included pit bulls, Great Danes and everything in between as therapy dogs.

As a rule, dogs are better suited to therapy than other animals. “Cats like relationships on their own terms,” says Dr. Johnson, who is president of the International Association of Human-Animal Interaction Organizations, a nonprofit working to advance the nascent science of understanding between humans and animals.

Ashley Talbott

Ashley Talbott, a fourth-year medical student at Virginia Commonwealth University’s School of Medicine, with Berkeley.

But other animals can serve other roles. Besides golden retrievers and black labs, Dr. Fine has worked with guinea pigs, bunnies, birds and bearded lizards. He recalls one lizard that had a severed tail and chronic constipation, which helped some children relate to her even more closely. “She was one of the nicest lizards I have ever met,” he says.

Of course, some patients are allergic or frightened around animals. Most doctors who practice with dogs inform patients before the first visit, and put the pup elsewhere for part of the day if necessary. But most find that practicing with a dog is a draw for patients, not a deterrent.

Animal-assisted therapy is still in its infancy. But research is expanding and interest is growing steadily. Some universities now offer undergraduate courses. VCU’s School of Medicine offers a course in human-animal interaction for fourth-year medical students and another for psychiatry residents.

“When you have psychiatrists who say, ‘I want to leave my practice and come and work with you,’ you know it’s an area of great interest,” says Dr. Barker.