Assistance dogs are often thought of as aides for people who are blind or visually impaired, but these animals make life easier for adults and children with a wide range of medical conditions.

Adam and Jeff are inseparable.

Whether at school, summer camp, or Little League games, Jeff is never far from Adam’s side.

Besides acting as a faithful companion, Jeff serves another crucial purpose.

The labradoodle is specially trained to alert Adam to significant changes in his blood sugar levels. That’s a potentially lifesaving measure for the 8-year-old, who has type 1 diabetes.

Since joining Adam’s family in February, Jeff has become an invaluable presence.

“Knowing that the dog is there to kind of be my backup and be that extra set of eyes on Adam is such a relief and [provides] such a peace of mind,” Adam’s mother, Morayea Pindziak, told Healthline.

The practice of medical alert and response is one of many ways in which service dogs can be trained to aid humans.

As the definition of disability has expanded to encompass a variety of physical and psychological conditions, so has the potential for service dogs to aid people with their capacity for steadfast devotion and affection.

The term assistance dog may bring to mind the image of a dog guiding a person who is blind or visually impaired.

This is a common example, but guide dogs are just one category under the larger umbrella of assistance dogs.

Melissa Winkle, registered and licensed occupational therapist, president of Dogwood Therapy Services, says people tend to use terms such as guide dog and service dog interchangeably.

However, each classification of assistance dog has unique capabilities developed through specialized training.

Winkle told Healthline that there are guide dogs who use their senses to help people in situations such as navigating changes in elevation and topography and avoiding oncoming traffic. There are also hearing dogs that alert people to the sources of sounds.

And service dogs perform a number of functions related to alert and response to help people with medical conditions such as asthma, epilepsy, diabetes, migraines, post-traumatic stress disorder (PTSD), and more.

As a diabetic alert dog, Jeff was trained to recognize the scents associated with a substantial spike or drop in his owner’s blood sugar levels.

To do this, Adam’s family sent Diabetic Alert Dogs of America samples of Adam’s saliva that were collected when his blood sugar levels fell outside his normal range.

Now when Jeff senses that danger zone he will sit and put his paw on someone to signal an emergency. Pindziak says that Jeff is adept at detecting the subtle chemical changes, sometimes before the glucose monitor does.

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It’s no coincidence that dogs are well-suited to assist humans.

“The story of dogs and humans goes back thousands of years,” said Steven Feldman, executive director of the Human Animal Bond Research Initiative Foundation. “Dogs are very clued into their people.”

Dr. Blanca Vazquez is an attending physician in neurology and director of clinical trials and outpatient services at the Comprehensive Epilepsy Center at New York University Medical Center.

She recognizes the power of human-canine relationships, particularly in terms of epilepsy treatment. For instance, whereas some animals might be spooked by their owner going into an epileptic seizure, dogs can respond effectively.

“Dogs seem to be very sensitive to emotional needs,” Vazquez told Healthline. Mariah Murray knows this to be true.

Murray has panic disorder, severe general anxiety disorder, and agoraphobia. She has taken medication to manage her symptoms, but she wanted an alternative form of treatment.

It was a documentary on dogs for jail inmates that inspired Murray to consider a service dog of her own. After raising $15,000 through a GoFundMe campaign, she was able to purchase a black German shepherd named Jax from the Dog Wish organization.

Among other needs, Murray told Healthline she wanted a dog who could provide tactile stimulation and deep pressure therapy, a calming mechanism in which the dog would apply pressure to Murray’s body.

Jax did both for Murray, giving her some relief from her debilitating symptoms. She describes Jax as a “goofy” and “cuddly” dog who was attuned to her emotions.

“He was very good at picking up on all sorts of things that I didn’t realize I was doing,” she said.

Jax recently died of cancer, but Murray says their bond strengthened as his health deteriorated.

While Murray is mourning the loss of Jax, she is now working with a new service dog named Aries on some of the alert skills that Jax had yet to master.

Ownership of a service dog does involve the reliance on an animal for certain needs, but many people would say their service dogs have supported their independence.

Even as Adam grows older and better understands his diabetes, Pindziak expects that Jeff will be sticking around. She acknowledges that as children get older they often want to test their limits, but Jeff will ensure that Adam won’t ignore his medical condition.

Vazquez has seen firsthand how service dogs can foster autonomy, particularly in young people who may feel isolated or alone because of their disability.

She notes that simply owning a dog creates a routine and promotes responsibility. Dogs also encourage people to go outside and interact with others, all while behind the physical and psychological barrier of an animal.

“All that can really help with socialization,” Vazquez said.

This approach can be especially useful for people who have anxiety disorders such as PTSD. If a person becomes overwhelmed by public or crowded spaces, a service dog can discreetly escort the owner away from the commotion.

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According to Feldman, there is a general consensus that dogs have a favorable impact on the quality of life for humans.

There are countless stories in which dogs are praised for their innate abilities, but to further advance research on the importance of assistance dogs, these stories need to be meshed with hard facts.

As one systematic review stated, “There are many anecdotal publications extolling the benefits of working with service dogs, but few rigorous studies exist to provide the evidence of the usefulness of this type of assistive technology option.”

That’s not to say there’s a total absence of research demonstrating impressive canine abilities, from sniffing out cancer to sensing earthquakes before they occur, but the scientific community is largely uncertain about how these processes work.

Vazquez doesn’t doubt the positive effect that service dogs have had on some of her patients, but she maintains the explanations behind some of the superhero-like skills that dogs possess are “all pure speculation.”

The service dog community Please Don’t Pet Me also notes that, “In most cases, the ability to sense an oncoming medical crisis is innate within the dog. This means that it is not a trained skill. In fact, in regard to many medical conditions, it is not yet known for sure how dogs can sense the respective episodes or crises.”

However, Vazquez says that some of these seemingly unbelievable circumstances could be attributed to dogs recognizing certain behaviors in their owners.

For example, she says, some actions are typical of someone who is about to have a seizure. If a service dog knows that its owner always turns to the left before they fall down, that could prompt the dog to bark for help as a seizure occurs.

When it comes to pairing service dogs with humans, individuality is important.

“It’s like every relationship,” Vazquez said. “You have to find the right animal for each individual patient.”

People are often looking for certain characteristics in a canine companion and some dogs just aren’t cut out for the job.

Owning an assistance dog comes with the same kinds of responsibilities that supporting any non-working dog would entail, but the stakes are even higher.

Assistance dogs require the utmost care and continuous training to ensure they can deliver a high level of performance.

But putting so much pressure on an animal brings up a number of ethical issues, Winkle explains.

Should a dog be placed in an environment that will likely be stressful? Should a dog be paired with an owner who struggles to take care of their own mental health? Winkle emphasizes that as helpful as assistance dogs for people with disabilities are, they’re not meant to be the only source of aid.

“Dogs can’t work 24 hours a day,” she said.

Keeping lifestyle factors in mind, potential owners need to do extensive research when selecting a service dog. It’s critical to seek out reputable organizations that have a history of turning out well-trained dogs.

Winkle encourages people to contact the Better Business Bureau, trainers, and former service dog recipients to assess the quality of service dogs. Feldman also recommends bringing healthcare providers into the conversation to determine whether a service dog is the best option.

“It is a long journey from deciding you want to get a service dog to actually having a service dog,” Murray said.

She called her experience an “arduous journey” but tells those who want to own a service dog “don’t give up even if it’s hard.”

Ultimately, that process is generally worth the effort. With Jeff, Pindziak says her son has a “built-in best friend.”

“He may have four legs and fur, but he’s definitely Adam’s true friend,” she said.

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