Risperidone is a longer-acting benzisoxazole derivative used for treating schizophrenia, and also the psychotic, affective, or behavioral symptoms associated with other disorders. This second-generation antipsychotic was designed to antagonize both D2 and 5-HT2A receptors. It has little effect on cholinergic and β-adrenergic receptors but does affect α2-adrenergic and histamine H1 receptors. In drug discrimination studies, risperidone antagonized LSD in a complete manner, and without displaying any LSD-like agonist activity.
