Toronto: Family doctors receive little or no information about harmful effects of medicines in the majority of drug promotions during visits by drug company representatives, according to an international study involving Canadian, US and French physicians.
Yet the same doctors indicated that they were likely to start prescribing these drugs, consistent with previous research that shows prescribing behaviour is influenced by pharmaceutical promotion.
The study, which had doctors fill out questionnaires about each promoted medicine following sales visits, has been published in the Journal of General Internal Medicine.
It shows that sales representatives failed to provide any information about common or serious side effects and the type of patients who should not use the medicine in 59 per cent of the promotions. In Vancouver and Montreal, no potential harms were mentioned for 66 per cent of promoted medicines.
“Laws in all three countries require sales representatives to provide information on harm as well as benefits,” says lead author Barbara Mintzes of the University of British Columbia. “But no one is monitoring these visits and there are next to no sanctions for misleading or inaccurate promotion.”
Serious risks were mentioned in only six per cent of the promotions, even though 57 per cent of the medications involved in these visits came with US Food and Drug Administration “black box” or Health Canada boxed warnings — the strongest drug warning that can be issued by both countries.
“We are very concerned that doctors and patients are left in the dark and patient safety may be compromised,” says Mintzes, an expert on drug advertising in UBC’s School of Population and Public Health.
Doctors in Toulouse were more likely to be told of a harmful effect in a promotional visit, compared to doctors in Canada and the US, according to the study. Researchers suggest that this may reflect stricter regulatory standards for promotion of medicines in France.
For the study, researchers recruited physicians to participate using random samples from lists of primary care physicians at four sites – Vancouver, Montreal, Sacramento and Toulouse. Among 704 eligible physicians contacted, 255 (36 per cent) chose to participate. Information was collected on 1,692 drug promotions at sales visits between May 2009 and June 2010.
Doctors were asked to fill out a questionnaire about the information provided for each promoted medicine following each visit they received from pharmaceutical sales representatives. Sales representatives regularly visit doctors’ offices to promote medicines by providing information, free samples and in some cases food and invitations to events. The study focused on how often information was provided about drug safety.
The team included researchers from UBC, York University, University of Montreal, University of California, Davis and the University of Toulouse.
Dr Tom Perry, an internal medicine and clinical pharmacology specialist at the UBC Hospital in Vancouver, who is not part of the study, expresses concern about the findings.
“Doctors learn relatively little about drugs in medical school, and much of their exposure to pharmacology after graduation may be in the form of advertising. If they are unaware of the potential harms from drugs they prescribe, patients inevitably suffer the consequences,” Dr Perry says.
Dr Perry also calls for much stricter control of drug advertising in Canada.