[The effect of methylphenidate on appetite and weight].

OBJECTIVES To better delineate in the medical literature the effect of methylphenidate on weight and appetite. METHODS A search on PubMed was carried out for articles published with no restrictions on language or year of publication using the terms: "methylphenidate"; "weight"; "appetite". RESULTS Methylphenidate increases dopamine and noradrenaline in synapses because of its blockage of the transporters of these monoamines in the frontal cortex and insular lobe. The intracerebral activity of methylphenidate is incriminated in the dysregulation of appetite due to its probable effect stimulating the disgust sensation generated after the activation of the insular lobe by the drug. The anorexigenic effect of methylphenidate has been demonstrated in preclinical studies although the dosage and the administration routes differ in animals from those used for human beings. In clinical studies, methylphenidate decreases the weight of children and adolescents during the first 3 to 6 months after its initiation due to the appetite reduction effect that it generates with a tendency of weight curves to rejoin the curves of subjects who did not receive the treatment a few years after its initiation. CONCLUSION The anorexigenic effect of methylphenidate does not persist over the long-term in children and adolescents who receive it.