(FORTUNE Small Business) – He worked as a commercial diver, retrieving cement samples for Seatec International hundreds of feet beneath the often turbulent South China Sea. It was a risky job, but the pay was good, and "it was an adventure for me at 19," William MacPhee recalls. He figured that if anything bad happened to him, it would come underwater. Instead, disaster struck from within. At age 24, MacPhee--by then employed on dry land in a printing plant--began feeling paranoid and delusional, and was hearing voices no one else heard. At one point he was found by police wandering in the street, unaware of what he was doing.

Diagnosed with schizophrenia in 1987, MacPhee was hospitalized six times and once attempted suicide. But in lucid moments, he kept searching for a way to regain the confidence and purpose he once felt--and he began to find it at his local library, in a book that helped him start his own business.

Once his doctors prescribed the right medication for his condition, MacPhee began taking entrepreneurial classes at Niagara College in Ontario, and developed a business plan for a magazine called Schizophrenia Digest. It appears to have been the first magazine of its kind to focus on a single mental illness. In 1994, after persuading his father to co-sign a bank loan for $45,000, he introduced the publication to Canada, editing it from his father's home in Ontario. The magazine's goal was to act as a "support group on paper" for readers with schizophrenia and their families, offering news on the latest medical research, success stories of schizophrenics, and advice.

When the publication he had started in his father's basement reached a circulation of 25,000, it motivated MacPhee to expand his audience. In 2003, from a new base in Buffalo, he teamed up with business partner Joanne Garvey to launch an edition with for the U.S., where 1.5 million people--less than 1% of the population--have been diagnosed with the illness, according to the National Mental Health Information Center, part of the U.S. Department of Health and Human Services. With a circulation of 50,000, the U.S. edition of Schizophrenia Digest brought in $500,000 in 2004 from subscriptions and ad sales, earning 94% of its ad revenue from pharmaceutical companies. The Canadian edition, which has a circulation of 25,000, brought in additional sales. Garvey says the next goal is to attract advertisements from national brands that are mainstream advertisers in other industries to help escape the "stigma surrounding schizophrenia."

Inspired by the success of Schizophrenia Digest, MacPhee and Garvey launched bp Magazine last fall. The quarterly publication, which addresses topics similar to those in Schizophrenia Digest, is aimed at patients with bipolar illness and their families. It broke even on its first issue and boasts a circulation of 50,000. "Bill has taken a risk by doing something in an area that hasn't been ventured into," says Eric Hufnagel, president and CEO of the National Schizophrenia Foundation in Lansing, Mich. "His accomplishments allow people to see what people with schizophrenia are capable of."

MacPhee, now 42 and a married father of three, agrees. "Having meaningful work is important," he says. "You have to find that spark." --HALAH TOURYALAI