According to the DSM-IV, all types of psychiatric disorders can be obs
erved in mentally retarded subjects, with prevalence estimated to be t
hree or four times higher than in the general population, Clinical fea
tures, longitudinal course and triggering factors are influenced by th
e characteristics of the intellectual disability, The aim of this pape
r is to discuss the specificity of the psychopharmacological therapy i
n mental retardation (sensitivity to specific psychotropic drugs, inci
dence of side effects, predictive criteria for evaluating risk factors
, etc.) and to propose an update in the pharmacotherapy in the most im
portant psychiatric disorders (mood disorders, psychotic disorders, be
havioral disorders, anxiety disorders, attention deficit disorders wit
h or without hyperactivity).