Direct to consumer advertising (DTCA) – advertising for prescription drugs – is only allowed in the United States (since 1997, when restrictions were loosened) and New Zealand. Drug companies pay for direct to consumer advertising (more than $4 billion in 20051) because they believe that it increases prescription rates. In a clever study published in the British Medical Journal in September2, Michael Law and colleagues looked at the prescription rates of the drugs etanercept, mometasone, and tegaserod in Canada. DTCA is not allowed in Canada, but English-speaking Canadians see these ads in US magazines and US TV commercials. The study authors found that prescriptions were higher compared to French-speaking Canada (supposedly not using the US media) for one of the three drugs studied (tegaserod). The study authors explain:
The European Union is considering changes in legislation that would allow direct to consumer advertising3. Not a good idea. Direct to consumer advertising not only means easily identified ads, but also information campaigns about diseases and treatments that are biased towards prescribing a particular drug.
The problems surrounding direct to consumer advertising are a reminder that open access to scientific and medical information is not enough. Similar conflicts of interest exist when car manufacturers would talk about climate change or crop producers about genetically engineered crops. We need not access to as much information as possible, but rather access to independent and objective information of high quality. Scientific journals and learned societies have traditionally played an important role in this. Once they've built up more reputation, science bloggers could have a bigger role in this in the future.
fn1. Donohue JM N Engl J Med 2007. doi:10.1056/NEJMsa070502
fn2. Law MR et al. BMJ doi:10.1136/bmj.a1055