For the last two years, Nancy Bierlmeier has been living with a constant companion she wishes would go away and leave her in peace.

Whether working, eating, conversing or trying to sleep, Bierlmeier is nearly driven to distraction by a loud, high-pitched hum in her ears that never goes away.

The condition, known as tinnitus, affects millions of people worldwide to varying degrees -- from mildly annoying to out-and-out ear-splitting.

Heard in one or both ears, or sometimes throughout the entire head, the sounds caused by tinnitus are usually described as a humming, ringing or buzzing. Some people are bothered only intermittently; for others, it is unrelenting.

For Bierlmeier, the sensation is like standing under a hydro tower and listening to the heavy thrum of a high-tension wire.

Except for her, there's no walking away.

"It's like the power line's between your two ears, right through your head -- it's a very high-pitched sound," says Bierlmeier, 50, who lives in Victoria with her 11-year-old son and works for the B.C. government.

"It's such an invasive condition. For me, I find that it competes with every second of my day. It's always trying to overtake my day, my thoughts. It's always there and I'm always aware it's there."

Maha Atrach, an audiologist with the Canadian Hearing Society in Toronto, describes tinnitus as a sound heard in the ears or head without any external stimulation.

The disorder can be caused by a number of physical conditions, including wax in the outer ear, a hole in the eardrum, or fusion or breakage of the three tiny bones in the ear that vibrate to transmit sound. (It can also be a side-effect of some medications.)

Most commonly, tinnitus occurs because of damage to the hair cells in the inner ear, often as a result of aging, says Atrach. Typically, the sound heard corresponds to the type of hearing loss.

Depletion of high-frequency hearing often produces a sharply pitched ringing sound, "like cicadas," she explains. When lower-register hearing perception goes, it can create a humming or roaring sound.

But for some people, no physical damage can be pinpointed to account for the condition.

"About 20 per cent of the population has tinnitus, so it's very common," says Atrach. "But only about five per cent are severely debilitated by it, where it really affects their working and social life, their family life."

While Atrach acknowledges that people with severe tinnitus are truly suffering, she says the condition is exacerbated when people focus on the sound and become increasingly anxious.

"A big part of it is the way that you perceive it and the way that you choose to deal with it," she says.

"So with people who are affected by tinnitus, when they hear it, they automatically associate it with a negative feeling. They start saying, 'Oh, my God. What is this sound? It's driving me crazy. Does this mean I'm going to go deaf? I can't live with it."'

"So every time they hear it, they pay attention to it in a negative way."

That was the case for Toronto retailer Gerald Small, who developed full-blown tinnitus about five years ago after going on a ride with his kids at Disney World in Florida.

Small, 48, had noticed a slight buzzing in his ears for many years, likely the result of too much noise exposure over decades of concert-going.

But after the Tower of Terror ride -- an elevator-like affair that involves plunging from a great height -- Small developed a high-pitched hum in his ears that has never disappeared.

"I had three months from hell, where it interfered with my work terribly. I couldn't put in a full day, and I found the tinnitus was on my mind 90 per cent of the day, constantly thinking about it."

Small said he consulted doctors, researched the condition on the Internet and finally contacted the Canadian Tinnitus Association for help.

"Gradually as I learned more about it and what was happening, I started to come to terms that I have this and there's a chance it may never go away," he says.

"At first you don't accept that. And I did run into some anxiety issues, which unfortunately with tinnitus, that's their dinner. They feed on it. They love anxiety, they love panic attacks, and it's a vicious circle."

For a short time, Small took anti-anxiety medications, which helped him shift his focus away from the noise in his head.

"It was a case of just live my life normally a or worry about this. I chose to forget about it as best as I can," he says. "I've been basically able to phase it out of my life."

In fact, shifting a patient's focus using a method called tinnitus retraining therapy, or TRT, has proven to be the most effective treatment, says Atrach of the Hearing Society.

With TRT, a patient has both ears fitted with hearing aid-like devices that generate "white noise" to compete with the buzzing, humming or ringing of their tinnitus -- in effect, redirecting the brain's attention.

Wearing the sound generators for six to eight hours a day has been found to make many people's tinnitus less intrusive and disturbing over time. (The devices are pricey, however, at $1,000 per ear.)

Patients also receive counselling that includes stress-reduction and tinnitus-diversion strategies, such as avoiding quiet environments and sleeping with a white-noise machine.

"Another thing I tell them is to not focus on it," Atrach says. "Try to focus on something else. Try to do activities that they enjoy."

For some people, a combination of therapies -- stress reduction, TRT and medications to regulate mood and sleep -- are most effective in dampening down the din, advises Elizabeth Eayrs, co-founder of the Canadian Tinnitus Association.

But she warns tinnitus sufferers against putting their hopes and dollars into herbal and other so-called cures offered on websites and in some health-food stores.

"The Internet is flooded constantly with quote-unquote remedies or miracles for tinnitus relief that don't work," she says. "There's a lot of snake oil."

Bierlmeier, who began developing tinnitus after going through a stressful divorce six years ago, has run the gamut of stress-relieving therapies, from acupuncture and chiropractic to vitamins and massage.

While some temporarily muffled the sound somewhat, nothing has silenced the cacophony completely.

Still, she is hopeful that in time she may find some peace of mind.

"There are days when I think, 'How am I going to get through the next hour?' And then that hour somehow becomes a day and then it becomes a week and a month and a year. And somehow you're still going, you're still living with it and you're still having days where you're really happy and positive."

"Deep inside, I don't know if it will ever go away, but I believe it will improve."