OTTAWA - Health Canada says the choice to restrict access to some prescription mental-illness drugs for on-reserve patients is based on the same expert advice that guides other publicly funded pharmacare programs nationwide.

Dr. Cornelia Wieman, a psychiatrist who has worked on First Nations reserves, said Health Canada will not cover some prescriptions for antipsychotics unless the patient has tried other drugs first. She made the comments last week to a parliamentary committee studying the high suicide rate in indigenous communities.

The issue is linked to Health Canada's non-insured health benefits program, which provides about $1 billion in annual coverage to eligible First Nations and Inuit people for a limited range of prescription drugs, dental care, vision care, medical supplies and equipment, medical transportation and mental health counselling not covered by private or provincial or territorial health insurance plans.

Health Canada responded to the criticism this week.

Spokeswoman Maryse Durette said that when it comes to figuring out which drugs the non-insured benefits program should cover, Health Canada relies on the advice of the Canadian Drug Expert Committee at the Canadian Agency for Drugs and Technology and Health, an independent organization that helps governments make informed decisions on health-care policies and funding.

That committee gives the same recommendations for all publicly funded drug programs in Canada, excluding Quebec, which are generally used by seniors, people on social assistance and others who need help paying for the higher drug costs associated with some diseases and conditions.

It is up to each jurisdiction whether or not to follow the advice.

"That approach is evidence-based and the advice reflects medical and scientific knowledge, current clinical practice, economics, ethical considerations, and patient and public impact," Durette wrote in an email.

"As a result, (non-insured health benefits) pharmacy coverage is generally aligned with that of the provinces and territories."

She also said that more than 99 per cent of pharmacy claims do not require any pre-approval.

For those that do, 94 per cent of them are allowed following a review.

Health Canada provided a chart comparing the recommendations of the committee, its non-insured health benefits program and pharmacare programs in all provinces and territories for eight different antipsychotic medications used for mental illnesses such as schizophrenia and bipolar disorder.

The data shows some variety across the country.

The Ontario drug benefits program, for example, does not impose any restrictions for those drugs, but most other jurisdictions follow at least some of the recommendations for most of them.

In some cases, the restrictions explicitly state that a program will not cover a certain drug unless the patient has failed with a less expensive alternative.

Brent Fraser, vice-president of pharmaceutical reviews at the Canadian Agency for Drugs and Technology and Health, said drug plan managers often tell the organization that cost is an important factor as they weigh whether a new drug on the market is worth including.

"It's the entire package that we need to provide comments on in order to help inform what the final decision is that's made by those jurisdictions," Fraser said.

Fraser also said the committee does not routinely review its recommendations to see whether they need to be updated, but this can happen if drug plan managers bring particular challenges or new evidence to their attention.

Dr. Doug Urness of the Canadian Psychiatric Association said the complex nature of reviewing so many medications can sometimes lead to concerns over whether the recommendations used by publicly funded plans are kept up to date with new medications and clinical guidelines.

"There is occasionally some frustration with disparities in coverage and I'm not exactly sure how to remedy that," said Urness, who chairs the association's professional standards and practice committee.

Wieman says Health Canada should focus on the needs of the population it is serving, rather than comparing its decisions to other plans.

"I don't waste my time thinking about (comparisons) between other drug plans," she said.

"I'm just interested in what is best for our patients."