A new study by the Canadian Medical Association shows 1 in 6 British Columbians have trouble affording prescription drugs. (CBC)

A new study published today in the Canadian Medical Association Journal says of all Canadians, British Columbians are least able to afford prescription drugs.

The study relied on data provided by 5,732 Canadians. People were asked if the cost of prescription drugs ever led them to stop medical treatment.

It found the people who are most likely to be unable to afford prescription medication are already in poor health, with no drug insurance and living in B.C, says lead author Michael Law, of the University of British Columbia.

"While we found 1 in 10 people across Canada had trouble with drug affordability, we found the number in B.C. was just under 1 in 6 -- so 17 per cent of people in British Columbia."

Law said the results took researchers by surprise.

"We weren't expecting that B.C. would be higher because we have a drug coverage program — Pharmacare," said Law.

But, he says, Pharmacare's high deductible could partially be to blame.

"Those costs might have something to do with it but it might also have to do with a lot of other things in B.C. -- like high personal debt," said Law.

"[It] stands to reason if you are spending more on housing and food than other people you are going to have trouble affording the other things you have to buy, like medicines."

The leader of B.C.'s official opposition says it's no surprise British Columbians have more trouble paying for prescription drugs than people in the rest of Canada.

NDP leader Adrian Dix says the B.C. government has put the squeeze on the poor and middle-income earners.

"I think [this is] recognition of high deductibles in our Pharmacare plans.  A recognition of high levels of inequality and just how vulnerable people are when they don't have extra or employee-related insurance."

Dix says British Columbians pay 40 per cent more for generic drugs than people in Ontario and Quebec.