Just months shy of his 90th birthday, the oldest and longest practising doctor in Kingston, Ont., has brought to an end a medical career that spanned nearly 70 years.

During his last week on the job, the still-spry but soft-spoken Dr. Edgar Barnett said he was sad to be leaving the career he had loved for so long.

"It's been my life, oh yes," Barnett told CTV Ottawa.

Barnett, who was born in England, graduated from medical school in 1948. He moved to Canada 20 years later and, after becoming certified here, practised family medicine in Kingston for several years.

But in the early 1970s, Barnett became intrigued by the then-growing field of hypnotherapy -- a form of psychotherapy performed while a patient is hypnotized.

Over the years, he has been fascinated with how a patient's subconscious mind can be used to help them in their conscious life with everything from quitting smoking to overcoming anxiety and depression.

"It's something that's a part of all of us; we all have a subconscious mind. All we hypnotherapists do is access that part," Barnett explained.

Barnett spent several years lecturing on hypnotherapy and wrote three books on the topic, including a textbook for other hypnotherapy practitioners, and a handbook for patients.

The desire to help others is what kept Barnett waking up early every morning to head into the office. And, he said he has been able to keep up his energy all these years by staying physically fit.

"I do get up early and I swim every day, so that keeps me going," he said.

Barnett also climbed the stairs every day to the same second-floor office that had been his home-away-from-home for close to 50 years.

"I always said: as soon as I can't get up the stairs, I'll retire," he said.

But now, the aging building where Barnett has had his office all these years is due to be torn down. Rather than try to move his practice elsewhere, Barnett decided to take the building demolition as an opportunity to close up shop.

"I learned they're going to pull the building down, so I thought I'd better get out before there are no stairs to come up," he joked.

For a man who loved his work, Barnett said he was sorry to be leaving it. But with his 90th birthday coming up in June, the soon-to-be retired doctor hopes to spend more time reading and playing the piano. He also plans on travelling, starting with a trip south next month.

It has been rewarding to help so many people over his career, doing what he loves, he said, and it’s what he will remember most as he begins his next chapter, away from the doctor’s office.

With a report from CTV Ottawa's Claudia Cautillo