Animal-Assisted Therapy: Right for Your Patients?

By: Robert S. Kennedy, MA

Animal-assisted therapy (AAT) is defined as a form of therapy that involves using an animal as a fundamental part of a person's treatment. Although the most commonly used animal is the dog, followed by the cat, many kinds of animals have been used in therapy. Most are small animals (rabbits, birds, fish, and gerbils), but some large animals such as horses and some farm animals have been employed.1

The range of problems that AAT has addressed is quite broad. While most people are aware of assistance animals, such as guide dogs for the blind, hearing-assistance dogs, handicap-assistance dogs and (more recently) seizure-alert and seizure-assistance dogs, clinicians and the general public are only slowly coming to understand that animals are used to assist in problems involving emotional distress and stress-related symptoms. Sometimes animals used in this context are referred to as "comfort animals." However, AAT animal interactions involve treatment that is targeted to specific areas such as cognitive functioning, social interaction problems, and even more extreme conditions such as autism.2

Animals as Part of the Healing Process

In ancient Egypt, dogs were used in healing practices. It was believed that being licked by a dog, especially in those areas of the body containing lesions or sores, could help heal the injury or cure disease causing it. This practice was adopted by the Greeks, and temples dedicated to Asclepius--their god of medicine and healing--often contained dogs trained to lick wounds. There is even a contemporary French saying, "Langue de chien, langue de medicine" which translates to "a dog's tongue is a doctor's tongue."1 Perhaps there is some validity to this, considering that research has shown that the dog's saliva actually contains a number of antibacterial and antiviral compounds, as well as some growth factors, that promote healing.3

AAT has been around for centuries. The earliest documented therapeutic use of AAT was in 1792 at York Retreat in England. It was implemented to improve the treatment of patients in the local psychiatric facility.4 Florence Nightingale also recognized the therapeutic value of pets and recommended pet birds to cheer up patients. The first documented use of AAT in the United States occurred in 1944, when the Pawling Army Air Force Convalescent Hospital near New York City treated soldiers with battle injuries or psychological trauma with trained therapy dogs.5

Sigmund Freud has been well known for being the "grandfather" of the field of psychology and psychoanalysis. His theories are omnipresent and his work has been studied by every psychology student. Interestingly, less known is that Freud was an advocate of using animals, specifically dogs, in treatment.

Freud's own companion dog, Jofi, accompanied him to every therapy session that he conducted for the seven years of Jofi's life. Freud believed that dogs have a "special sense" that allows them to correctly "judge a person's character." Additionally, he believed that having a dog present in therapy would help calm his patients. Freud noticed that Jofi had a way of attending to tension in the therapy room and would lie down near calm patients but stay across the room when the patient was tense. He was able to use this information to understand and conceptualize his patients in session. Jofi also helped the great psychoanalyst determine when a therapy session was finished by unfailingly getting up and moving toward the office door when the hour was up. There is very little written about what Jofi specifically did in session that may have been therapeutic or what results he facilitated for Freud's patients. Nonetheless, it is interesting to note that AAT has been around, in some form or another, since the beginning of the field of psychoanalysis.6

In 1961, Boris Levinson, PhD, a New York psychologist, wrote about his dog, Jingles, who significantly helped a severely disturbed and uncommunicative child during some therapy sessions. The dog was left alone with the child for only a few minutes, but when Dr. Levinson returned to the room, the child was talking to the dog. He coined the term 'pet therapy' and later published his studies of this phenomenon in two books: Pet-Oriented Child Psychotherapy7 and Pets and Human Development.8 In these works, he describes the therapeutic use of animals in a variety of institutional settings for emotionally disturbed children and in schools for the blind, deaf, and physically disabled. He believed that pets serve as 'transitional objects' allowing the child to relate first to the animal, then the therapist and eventually to other individuals.5,9

Physiological Impact of Animal-Assisted Intervention

Many authors note the sense of calm that animals bring to the lives of humans. For example, Phil Arkow, an international lecturer on AAT, states, "Animals have been called ambassadors from the natural world, bringing a sense of calm and of natural cycles into our increasingly urbanized, mechanized world."10

A number of studies have studied the impact of AAT on human physiology.11,12 Beck and Katcher used direct physiological measures to show that when a person interacted with, or even was simply in the presence of, a friendly dog, there were direct changes in their physiological responses. Breathing became more regular, the heart beat slowed, muscles relaxed, and there were other physiological changes, suggesting a lowering of sympathetic nervous system activity. Because it is the sympathetic nervous system that responds to stress, this indicated that the dog was clearly reducing the stress levels of the people in its presence.13

A particularly interesting investigation by Cole and colleagues examined both physiological and subjective anxiety variables in patients who were hypertensive. Their participants were assigned to three study arms: a human and animal-assisted intervention, a human-only intervention, and a "usual care" intervention. The authors found that, compared with both control groups, the animal-assisted group had significantly greater beneficial decreases in systolic pulmonary artery pressure, pulmonary capillary wedge pressure, epinephrine, and norepinephrine both during and after the intervention. The participants in the animal-assisted group also had the greatest decrease in state anxiety. These results indicate that the sense of calm and relaxation that comes from association with animals may not only be a subjective feeling but also has evidence in the associated reduction it brings in terms of physiological stress levels.14

AAT has been used in critical and acute care, rehabilitation, outpatient clinics, long-term care facilities, nursing homes, oncology and hospice care, and prisons, as well as during home visits.5 AAT has also been in use and studied in a broad variety of patients and in an array of clinical situations (see Table 1).

The goals of ATT can be both quite varied and tailored to the needs of a particular patient. See Table 2 for examples.

Defining Therapy Versus Visitation

AAT is a scheduled intervention designed to improve a patient's cognitive or physical functioning, with specific short- and long-term goals. It is generally done by a skilled practitioner, and the patient/animal interaction is usually one-on-one. AAT uses specifically trained therapy animals, not the patient's own pet.5

Animal visitation is a short-term intervention intended to improve the patient's sense of well-being and reduce loneliness. Visitation can help accomplish short-term goals such as reducing the need for pain medication. Visitation may be provided by a single animal/volunteer or a group of animals/volunteers, for example, in a visit to a nursing home.5

There is a certification process for AAT. Certification helps to unsure that the animals brought into a facility will behave in a predictable manner. A number of non-profit organizations, both nationally and internationally, train and certify AAT. For example, the Delta Society23 is an international organization that certifies and registers animals who provide AAT; its mission is to improve human health through service and therapy animals. They unite people who have mental and physical disabilities and patients in health care facilities with professionally trained animals in order to help improve patient health. (See Resources for additional organizations.)

As stated above, dogs are the most frequently used therapy animals. Their behavior is the most predictable and the easiest to test. Working, herding, and sporting dogs excel at therapy work. Although breed has an influence on behavior, temperament and training of the individual dog are the two most important attributes of a great therapy dog.5

Equine-assisted therapy (EAT), also termed hippotherapy (from Greek hippo meaning horse), has also been used for many years. The traditional focus of hippotherapy has been physical rehabilitation to promote balance and improve body control. It has been used to treat individuals with cerebral palsy,24 multiple sclerosis,25 stroke,26 and a number of other physically disabling disorders. More recently, it has been used with individuals with autism spectrum disorders,27 and a recent program uses EAT for PTSD in veterans.28

Possible Risks of Animal-Assisted Therapy

Possible risks and concerns of AAT include fear of animals, animal allergies, and cultural biases. These can be eliminated with proper screening of both the patient and the animal. Of greatest concern in hospitals, particularly in critical care units, is safety and sanitation.29 In addition, some patients may have compromised immune systems.30 Certification programs with strict guidelines for safety and sanitation for AAT help to ensure quality control.29 Most AAT programs collaborate with a veterinarian for enhancing animal care.4 Guidelines from the American Veterinary Medical Association discuss the benefits and risks of AAT and ways to promote safety of both humans and animals.31 Patient selection should be an important consideration. Some people are afraid of animals, particularly large ones. It is important to assess a patient's willingness to participate in AAT. A preliminary step often involves visiting the animal or therapeutic site to evaluate the potential relationship and interaction.30


Complementary therapy is defined as treatment that supports, facilitates, or enhances conventional treatment strategies. AAT describes a complementary intervention with animals, usually dogs that are trained to be obedient, calm, and comforting.2,29,32 AAT is not a solution for all health problems, nor is it appropriate for all patients. When using it as a complementary therapy, however, AAT has the potential to provide physiological and emotional benefits for many people.18 Animals offer a unique kind of support and unconditional love that human companions often cannot offer. They offer comfort on demand, in a quantity tailored to the patient's need, without the expectations of gaining something in return.20,33

Clinical Connections

Post-Compass Questions™

Your responses to this issue's Compass Questions™ will be added to an ongoing needs assessment for educational programming in this important area. Responses to this issue's questions will be reported in an upcoming issue.

Question #1
Now that you have read this Compass Points article, have you increased your knowledge of animal-assisted therapy as a clinical option for selected patients?
Very much
Not at all

Question #2
Now that you have read this Compass Points article, will you consider recommending animal-assisted therapy for selected patients in your practice?

Question #3
How interested are you in participating in additional educational activities on animal-assisted therapy as a therapeutic option?
Extremely interested
Very interested
Moderately interested
Somewhat interested
Not at all interested


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