Pharmacoproteomics may be defined as proteomics applied to the discovery of new therapeutic targets and to the study of drug effects. Proteomics is a powerful technique for analyzing the protein expression profiles in a biological system and its modifications in response to a stimulus or according to the physiological or pathophysiological states. Thus it is a technique of choice for the discovery of new drug targets. It is also an interesting approach for the study of the mode of action of treatments and preclinical drug development. This pharmacoproteomic approach may be particularly useful for the research of new molecular alterations implicated in type 2 diabetes and/or obesity and for the further characterization of existing or new drugs.