Most family doctors say they receive little or no information about harmful effects of medications when visited by drug company sales representatives promoting their products, a survey of Canadian, U.S. and French physicians has found.
The study, which involved 255 doctors in Montreal, Vancouver, Sacramento and Toulouse, France, shows that sales reps 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 promotions.
In Vancouver and Montreal, no potential harms were mentioned for 66 per cent of promoted medicines, says the study published online Wednesday in the Journal of General Internal Medicine.
"Laws in all three countries require sales representatives to provide information on harm as well as benefits," said principal researcher 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 6 per cent of the promotions, even though 57 per cent of the medications involved in these visits came with U.S. Food and Drug Administration "black box" or Health Canada boxed warnings – the strongest warnings issued in both countries.
Physicians in Toulouse were more likely to be told of a harmful effect by sales reps, compared to doctors in Canada and the United States, possibly reflecting stricter regulatory standards for promotion of medicines in France, researchers said.
"We are very concerned that doctors and patients are left in the dark and patient safety may be compromised," said Mintzes, an assistant professor at UBC's school of population and public health.
To conduct the study, researchers recruited family doctors to participate using random samples from lists of primary-care physicians in the four cities.
Doctors were asked to fill out a questionnaire about the information provided for promoted medications following each visit from a pharmaceutical sales rep. In all, they provided information on almost 1,700 drug promotions between May 2009 and June 2010.
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.
Despite the lack of information on potential adverse effects, many of the surveyed doctors said they were likely to start prescribing these drugs, consistent with previous research that shows prescribing behaviour is influenced by pharmaceutical companies' promotion.
"We were surprised that most of the time they were somewhat or very likely to increase their prescribing or to start prescribing [a promoted drug]," Mintzes said. "The problem is this is a source of information that is often used, consciously or not, to inform prescribing decisions. There's a serious problem in terms of ensuring that doctors are getting adequate safety information as a background to prescribing decisions."
Dr. Tom Perry, an internal medicine and clinical pharmacology specialist at the UBC Hospital in Vancouver, expressed 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," said Perry, who was not involved in the study. "If they are unaware of the potential harms from drugs they prescribe, patients inevitably suffer the consequences."