Pharmaceutical companies that advertise their prescription drugs directly to consumers may not be getting as much bang for their buck as they – or their critics – assume. Such advertisements do little to boost the rate at which doctors prescribe the drugs, a new study finds.

Direct-to-consumer ads have long been a controversial part of pharmaceutical marketing. Both proponents and opponents assume the ads are effective at increasing prescription rates, with the former arguing the ads benefit society by raising awareness of diseases and their treatments, and the latter arguing they pump up demand for drugs unnecessarily.

However, consumer advertising is usually accompanied by other marketing efforts directly to doctors, making it difficult to tease out the effect of the ads alone.

Enter Michael Law, a health policy researcher at Harvard Medical School in Boston, Massachusetts, who realised that Canada provides a perfect test case.


Language barrier

Doctors throughout Canada receive the same vigorous sales pressure as their American counterparts. Their English-speaking patients also see direct-to-consumer drug ads on US television stations, which most Canadian households receive.

However, Canadian TV is prohibited from running similar ads, so French-speaking patients should have far less exposure to the ads because of the language barrier, Law reasoned.

He and his colleagues chose three drugs that were widely advertised to consumers in the US and compared prescription rates in predominantly French-speaking Quebec versus in the predominantly English-speaking rest of Canada.

Only one of the three – a treatment for irritable bowel syndrome called Zelnorm – showed any spike in prescription rates in English Canada after ads began in the US, and even this advantage vanished within a few months.

Patient power

“All of this hoopla about drug advertising on TV might be exaggerated,” says Stephen Soumerai, a health-policy researcher at Harvard Medical School, who also worked on the project.

The evidence suggests that advertising to consumers does little to increase the sales of most drugs, perhaps because consumers must go through their doctors to get a prescription rather than just going to a shop, as with most products advertised to consumers.

While it is important not to generalise too far from a study of just three drugs, Law’s result might indicate that television advertising of drugs is losing its punch in an era where patients are inundated with information from news media and the internet, says David Henry, CEO of the Institute for Clinical Evaluative Sciences, a health services research institute in Toronto, Canada.

“Maybe we just have to accept that consumers are going to take more control,” says Henry.

Journal reference: British Medical Journal (DOI: 10.1136/bmj.a1055)