UBC Reports | Vol. 48 | No. 5 | Mar. 7, 2002

Drug advertising may pose health risk warns researcher

Requests for advertised drug influence mds, says study

When marketing meets up with medicine, results can be harmful to health, says a UBC researcher. Barbara Mintzes, a PhD candidate in the Dept. of Health Care and Epidemiology, led a study of how advertising affects prescribing practices in Vancouver and Sacramento, Calif.

The study was published last month in the British Medical Journal. Doctors were more likely to prescribe a drug that a patient had seen advertised and specifically asked for even when the doctor was uncertain about its appropriateness for that patient, according to Mintzes and co-investigators from UBC's Centre for Health Services and Policy Research, York University and the University of California at Davis.

"One of the big concerns about this kind of advertising is you're pushing people to use very new drugs before we know very much about either their risks or their longer term benefit," says Mintzes, who has worked for Health Action International, a non-profit global group interested in a more rational use of medicinal drugs.

The study of 78 primary care physicians and 1,431 patients used questionnaires to determine the frequency of patients' requests for prescriptions and of prescriptions resulting from requests.

Findings showed that physicians prescribe drugs in response to almost three-quarters of requests and that doctors are ambivalent about their prescription decision in about half of cases where they are responding to patient requests for an advertised drug. They reported ambivalence in only about one case in eight when not prompted by a patient request.

The study looked at drugs having the 50 biggest advertising budgets in the U.S. or which had been covered by Canadian media.

Only the U.S. and New Zealand allow advertising of drugs directed at patients. U.S. pharmaceutical companies spent $2.5 billion US in advertising prescription drug products to the public in 2000, says Mintzes. Although this amount is less than 20 per cent of the total advertising budget, it is the fastest-growing budget item, she adds. Retail drug sales in 2000 totalled $145 billion US. The Pharmaceutical Advertising Advisory Board, part of Health Canada, prohibits such advertising but enforcement is lax, she says.

She points out that Canadians still get the messages through American cable and satellite TV, magazines and the Internet. In addition some ads are allowed that fall between the cracks of regulations concerning promotion, such as disease-oriented ads that advise patient to see their doctor.

"It's very clear that the industry has been pushing the limits of the law," she says.

Even if it is not explicit, it is still promotional activity posing as education, she adds. Critics of the research say it does not address the key question of how the advertising-influenced prescribing affected patients' health.

"Medicines have prescription-only status because they are judged to be too risky to be used without the advice of a physician. We are concerned that the protection offered by prescription-only status is being seriously eroded if patients request drugs in response to advertising and doctors prescribe requested drugs in spite of being ambivalent about the choice of treatment," says Mintzes.

more information

Visit the British Medical Journal Web site at bmj.com/cgi/content/full/324/7332/278