Although the appetite suppressant benfluorex (Mediator°) has been on the market in France for more than 30 years, no convincing data are available as to its benefits.

Its adverse effects, which have been known for a long time but little publicised, can be severe: digestive and neuropsychiatric disorders (agitation, confusion, delirium, etc) and adverse cardiovascular effects. 28 cases of pulmonary arterial hypertension and around 30 cardiac valve disorders affecting one, two or even three heart valves have been recorded by the French regional pharmacovigilance centres in Besançon and Brest.

All of these cardiovascular and neurological adverse effects resemble those that led to the market withdrawal of two other appetite-suppressant amphetamines: fenfluramine and dexfenfluramine.

In France, it took until November 2009 for the French Health Products Safety Agency (AFSSAPS) to finally suspend its marketing authorisation for benfluorex, after having authorised copies of the drug in 2008. Whereas Spain simply withdrew benfluorex from the market years ago and outlawed compounds containing the drug.

Just how many serious adverse effects, without any benefit in return, could have been avoided during all these years of dithering?

> See also: "Benfluorex: still on the market, despite numerous severe adverse effects", November 2008

©Prescrire 26 November 2009