[Paracetamol: a promising ancestor].

More than a century after its discovery, paracetamol remains the most widely used analgesic around the world. Despite elderly, its beneficial effects (analgesic, antipyretic), its undesirable effects and its toxicity are an inexhaustible source of publications. Indeed, mechanisms underlying these actions are unclear. A better understanding of its analgesic mechanism of action will highlight molecular(s) target(s) involved in its effect. This will allow the design of more efficient analgesics with equal safety than paracetamol. Several systems appear to be involved: the serotoninergic system and the prostaglandin one. Two other endogenous systems presently need to be added: the cannabinoidergic and vanilloidergic systems. Recent studies reveal a new vision of paracetamol: a pro-drug which needs to be bio-transformed to exert its analgesic effect. These new data forebode that paracetamol did not finish surprising us.