Reviews studies examining effects of pharmacological interventions for children with mental retardation and autism. Discusses information regarding stimulants, neuroleptics, anticonvulsants, antianxiety drugs, and antidepressant drugs as measured by their effects on laboratory and clinical measures of activity level, self-injurious behavior, and stereotypies. Presents information regarding dose levels, positive effects, and possible negative side effects. (Author/NB)