CBC News asked Health Canada in December 2007 to comment about the efficacy of the agency's advisory system. Health Canada initially did not respond, though later agreed to an interview with the CBC's David McKie. Here is an excerpt of the CBC interview with Dr. Marc Berthiaume, a practising physician and director of Health Canada's marketed pharmaceuticals and medical devices bureau, which monitors heath products, including prescription drugs.

David McKie: When it comes to warnings, advisories and "Dear health-care professional" letters, etc, what is the purpose of them?

Marc Berthiaume: The purpose of warnings is to communicate to stakeholders — mainly the public and prescribers — emerging information around risk that has been discovered for drugs once they have been put on the market. So often, there is a bridging mechanism between the time that we integrate that additional information into the labelling, which is the tool that prescribers should use whenever they decide to prescribe a specific drug to a specific patient.

McKie: And when you put out a warning, is there any expectation on the part of Health Canada with regard to what should happen to prescription rates?

The health minister's powers

Health Canada told CBC News that its powers are limited to publishing safety alerts. If warnings remain unheeded, Health Canada suggests the law ties its hands. Healthcare advocates argue the law gives the minister the power to intervene if warnings are ignored.

Section 4 of the Department of Health Act sets out the duties of the minister, which "extend to and include all matters over which Parliament has jurisdiction relating to the promotion and preservation of the health of the people of Canada…" Among the specifics are:

• The promotion and preservation of the physical, mental and social well-being of the people of Canada.
• The protection of the people of Canada against risks to health and the spreading of diseases.

Marc Berthiaume: Our main focus when we disclose this information is that we want it to be part of the decision-making information that a physician uses when he prescribes. We have developed over the years different ways to increase our outreach of that safety information to get to the physicians and other types of prescribers and patients. For example, the [amount] of risk communication has increased by two and a half times over the past four years. We also have a list where people can register and they can receive all the risk communication [information] that Health Canada sends out. Once that information is in the hands of the physician, the decision to take one drug or another is part of their own professional decision — this is not something that we control. Our mandate at Health Canada is to bring additional safety information to the prescriber, and the way they handle that information is part of their professional autonomy.

McKie: So it would be fair to say that in your risk communication you talk about a drug carrying certain dangers, your expectation is that there would be some sort of influence on prescription rates, that they go down?

Marc Berthiaume: It depends. I don't think the prescription rate is an outcome that can be used to measure the impact of a risk communication for all risk communications. In certain instances, a drug that has a certain indication, there may not be a lot of other alternatives, even if you identify additional risks with that drug. If there is no safe alternative, you cannot expect a decrease in the prescribing rates. It's more complex than just looking at prescribing rates.

McKie: But you just said that prescription rates is something that you do monitor.

Marc Berthiaume: We do look at it for certain drugs that we have investigated, yes.

McKie: And why do you look at the rates?

Marc Berthiaume: It's a way to document the effectiveness of some interventions. One perception that's out there is that risk communications don't work. That perception is based on certain cases that have had had a certain profile. As a professional involved in communicating risk, I thought it was important to look into certain cases where we could document that we did have a good impact on the prescribing rates and on the use of a drug. So if the prescription rate decreases, it may be a marker that, yes, there has been a change in the prescribing patterns. If there is no decrease, that cannot be assumed that it is a sign of failure of the risk communication.

McKie: But it's not a good sign…

Marc Berthiaume: Well, ultimately, the objective is to get the information into the hands of the prescriber and the consumer. We've increased our outreach capacity, as I've said before. We are successful in getting the information out. Once it's in the possession of the physician, the decision to prescribe is the professional judgment of the prescriber.

McKie: In our story, we reported that there were two warnings in June 2005 about increased risk of death. The sales data shows that there was an increase between seven and 40 per cent for a 24-month period after that warning. What is your reaction to that?

Marc Berthiaume: One thing that has to be kept in mind is that drug safety involves numerous organizations. Drug manufacturers have an important role to play when it comes to keeping track of the safety record of their drugs. Regulators do approve the drug for market. Physicians have a role to play in choosing drug A over drug B. Pharmacists have a role to play in the information they disclose to the patient. Patients have the ability to ask the physician or pharmacist or to get information on the web or from other sources. On the case that you're referring to, Health Canada has been very diligent in posting, first in 2002 for the drug risperidone (Risperdal), and then in 2004 for the drug olanzapine (Zyprexa), and then another one in 2005, disclosing all the risks about the drugs. Health Canada has also been very diligent in putting in all the product monographs and clear warnings that these products should not be used in patients with dementia, with the exception of risperidone, which has an indication in very specific cases. So I think Health Canada has done its duty to bring all the information to the point of care so that an informed decision can be made. However as you probably know, there is the ability for the physician to prescribe off-label, which is the ability to prescribe a drug outside its prescribed use. It's part of the provincial authority, whether it's the provincial colleges of pharmacists or physicians and the drug plans, to decide if they want to intervene at that level to modify prescription behaviours.

McKie: Understood, but you talked about the fact that in order to judge the effectiveness of your advisories, one of the areas that you did look at was prescriptions. Here, the rates are still going up. So doesn't that give Health Canada some pause for concern?

Marc Berthiaume: As I said, one of the reasons we looked at prescribing rates was to demonstrate that there was an effect on risk communication in certain situations. Once the information is out there, it's the role of other stakeholders to take that information into consideration. For examples: organizations that develop practice guidelines; organizations that decide what drugs are reimbursed and under what conditions. These organizations have tools to influence prescription behaviour that are outside the mandate, scope and authority of Health Canada. So even if in certain circumstances the information is out there, the impact of that information on prescribing is outside of our control.

Here, on your story, you took the number of prescriptions as a marker of the failure of the risk communication. I haven't looked at the numbers, but I think it's over-simplistic to reduce the success of the risk communication based on the fact that there's been additional use. The reason for the additional use should be addressed to the medical community.

McKie: Are you saying that Health Canada has no scope or no responsibility to monitor if its message is getting out?

Marc Berthiaume: As I said, we are monitoring the effects of some of our interventions, but we are working within our mandate, our authority and the tools that we have in the regulations. We cannot go outside of that. Regulating the practice of medicine is outside of our authority.

McKie: I'm not talking about regulating medicine. I'm just talking about whether your message, your risk communication is reaching its targeted audience.

Marc Berthiaume: We conducted a survey, for example with the Canadian public in 2006. One-third were aware of the existence of Health Canada's website as a source of health product safety information. Two-thirds were aware of the fact that Health Canada posts warnings and advisories and is a source of that type of information.

For doctors, if you take the Zyprexa and the risperidone risk communication, they were directly sent physically to them by mail with an envelope bearing the mention that Health Canada endorses safety information, so it's about as far as we can get. We cannot open the letter for them. We cannot make them read them.

McKie: Should the doctors be doing more, then? Should they be opening those envelopes?

Marc Berthiaume: I think they are.

McKie: They say they're not. They don't always … they don't necessarily pay attention.

Marc Berthiaume: We've had good discussions with the provincial regulatory authorities, the colleges of pharmacists and physicians, and they do help us increase the awareness among their members about the information that we get to them. I think as a physician myself, you have to screen the information that gets to you, and you have to identify credible sources of information.