Right Right after residency,I took a summer job in a family practice in a beach town on Long Island. One day,a woman in her early 40s asked me to prescribe fen-phen,a weight-loss pill that combined the fenfluramine and phentermine and was being heavily marketed at the time.
She certainly didnt look overweight,and I asked her why she wanted weight-loss pills. I was also a little leery of the whole idea of weight-loss pills,which seemed like a Band-Aid approach to what was usually a lifetime pattern of poor eating habits and inactivity.
I started to explain my concerns,noting that every medication has side effects. But she cut me off.
Ive taken fen-phen before, she said. I just need a prescription from you,not a lecture. When I reiterated my hesitations,she stormed out in a huff.
A month later,an article in The New England Journal of Medicine linked fen-phen to heart valve abnormalities. Shortly after,the medication was pulled from the market.
The encounter in Long Island came to mind recently when I read an essay called Lemons for Obesity in Annals of Internal Medicine. The author,Dr Michael S Lauer,was one of only two members of a 22-member Food and Drug Administration panel who earlier this year voted against approval of the new weight-loss drug Qnexa,a combination of phentermine and topiramate,an epilepsy drug with the side effect of weight loss.
Dr Lauer gives a brief history of Qnexas approval process,including concerns of cardiovascular side effects and possible risks of cleft lip and cleft palate in babies born to mothers taking the drug. Then he makes an interesting analogy to the used-car market,citing the 1970 paper The Market for Lemons that eventually won a Nobel in economic science for its author,George Akerlof.
Lemons are harder to sell than quality products,so sellers do more promotion and offer steeper discounts,Dr Akerlof had argued. In addition,used-car buyers (like patients) know much less about the product than used-car sellers (and pharmaceutical companies). The combination of information asymmetry and aggressive marketing can allow lemons to dominate the market.
Fen-phen,ephedra,sibutramine and phenylpropanolamine all were pulled for safety concerns. A drug popular in Europe,rimonabant,was denied approval in the US because of side effects. The lone prescription drug currently available in America for weight loss,orlistat,offers only minor weight loss with the trade-off of major stomach problems in the form of oily,greasy stools.
The weight-loss field is strewn with lemons,more so than other areas of medicine,Lauer argues. Its hard to know at the outset which new drugs are lemons and which will become game-changers. But any drug that arrives on the scene with heavy promotion and only modest benefits deserves the same circumspect attitude as that too-good-to-be-true used car.
(The author is a doctor,professor,author and editor of studies in medicine)