Risperidone (Risperdal®) is a recently developed antipsychotic drug with the combination of serotonin-5HT2A-and dopamine-D2-antagonism (SDA). In patients with schizophrenia, risperidone reduces positive symptoms at least equally effective as haloperidol, however, risperidone has a reduced propensity for the induction of extrapyramidal symptoms.

In addition, available evidence indicates that risperidone may be an effective treatment for negative symptoms. The optimum daily dose range is between 4 and 8 mgfor most patients. In this review article, risperidone is compared with some other (classical and atypical) neuroleptics. In addition, the pharmacological and pharmacokinetic properties of risperidone are reviewed.

A concise review is given of the importance of the atypical antipsychotic drugs clozapine, sulpiride, remoxipride and raclopride. Both the concept of atypicality and the pharmacological profile of these compounds is discussed. The newly developed atypical antipsychotic remoxipride has been studied in several double blind studies. In virtually all of these studies a reduced propensity for the induction of extrapyramidal symptoms was found.

These findings implicate that atypical antipsychotics may also not induce tardive dyskinesia. In addition to the treatment of acute schizophrenia, these compounds might be of use in the treatment of treatment resistent schizophrenia (clozapine), tardive dyskinesia and psychosis during the course of Parkinson's disease.