When Katrina O’Neill’s first saw Noah, the black and white terrier puppy that was to become her constant companion, her spirits lifted. She knew that the puppy would not only make an ideal pet but would also cheer up her aunt, Angela, who was unwell. “He was a godsend. Anytime either one of us was feeling upset, Noah would be there to lick away our tears. He is such a caring wee dog,” she says.

A year after she got Noah, O’Neill, 22, was at a birthday party where she met Kate Jack, the regional organiser of Pets As Therapy (PAT), a charity that has been taking dogs into hospitals, nursing homes and hospices for more than 20 years in the belief that animals can play a vital part in reducing stress and the need for medication as well as helping to speed up a patient’s recovery.

Jack suggested that Noah’s friendly nature would make him a perfect candidate to become a dog visitor. O’Neill agreed and Noah started to make regular house calls at a residential home in Inverness.

“The residents absolutely love Noah,” says O’Neill. “He gives them something to look forward to. They get to cuddle him, pat him and feed him biscuits. He brightens everyone’s spirits. I know myself that all my problems vanish whenever I see Noah and I think the residents feel the same way.”

The conviction that pets can help alleviate stress and in some cases illness is one that is taking hold among medical professionals as well as animal lovers.

For Abby (not her real name) her two-year-old beagle-corgi cross, Mungo, is more than just a pet. “This smelly thing,” she says pointing to the dog, “is my guardian angel.” She might sound like any other devoted dog owner, but Abby insists their story is different: she credits Mungo with bringing her back from the abyss of clinical depression.

Eighteen months ago, Abby felt that the rug had been pulled from beneath her. A five-year relationship with her boyfriend had ended, their flat had been sold and the prospect of rebuilding her life on her own seemed like a struggle Abby didn’t have the strength to see through.

“I took the break-up really badly. I was crying every day, I was calling in sick to work and I couldn’t face meeting up with my friends who were all blissfully coupled up,” says Abby.

After four months, feelings of heartache had given way to depression. “I was panicking before leaving the house, not sleeping properly, falling to pieces over the tiniest little mishap at work. I couldn’t cope with my life any more.”

Having suffered badly from depression in her teens, Abby made an appointment with her GP, who suggested she begin a programme of anti-depressant medication, and join a six-month waiting list for counselling. But Abby was determined to avoid prescription drugs, having heard horror stories about side effects and addiction. A friend suggested the common-sense option of getting a canine companion. Murray was sceptical but in the absence of any other solution, was eventually persuaded to give it a try.

“At first he was just something to hug. He got a quick walk along the canal and then I generally spent the rest of the evening sobbing into his fur,” recalls Abby.

But she soon found comfort in the routine of dog walking and stick throwing. Eighteen months on, Abby says she would never have believed a pet could have such a dramatic effect on her psychological wellbeing.

But can patting a pooch really provide a reliable alternative to pills? Critics have already mocked the idea of taxpayers’ money being used to provide pets on prescription, following the controversial launch of a pilot scheme in south London, but some believe that the healing powers of animals should not be ignored.

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