I would like to thank Dr Carracedo-Martínez for his interest in our work, and for his valuable comments [1]. Obviously, health insurance companies do not invent such measures out of the blue but on the basis of warnings from regulatory authorities such as the European Medicines Agency. ‘Dear Healthcare Professional Communications’ (DHPCs) on this issue had already been sent before July 2007, and the decline in prescribing already occurred before that month [2]. It is likely that several local and regional guidelines also changed and further contributed to the decline. Such consequences from DHPCs are helpful to endorse safer prescribing. In this case, health insurers re-emphasized that thiazolidines should be prescribed to non-insulin-dependent diabetics with a contra-indication for metformin and sulfonylureas, or in those on double or triple therapy with metformin, a thiazolidine, and a sulfonylurea. From an epidemiological viewpoint, such measures are considered as intermediates rather than as direct causal factors for prescription decline.