Risperidone - A review of its use in the management of the behavioural andpsychological symptoms of dementia

Risperidone is a benzisoxazole derivative which has proven efficacy against the positive and negative symptoms of schizophrenia It has mon recently be en investigated and shown efficacy as a treatment for the behavioural and p sychological symptoms associated with dementia in the elderly. Risperidone has pharmacological properties resembling those of the atypical antipsychot ic clozapine and an improved tolerability profile compared with the convent ional antipsychotic haloperidol. Risperidone has antagonistic activity prim arily at serotonin 5-HT2A and dopamine D-2 receptors. In the first 2 large, well controlled trials of an antipsychotic agent used in the treatment of elderly patients with Alzheimer's dementia, vascular d ementia or mixed demential risperidone 1 mg/day was at least as effective a s haloperidol and superior to placebo. as assessed by the rating scales for global behaviour, aggression and psychosis. In extension phases of the 2 t rials, clinical benefits were maintained for treatment periods of up to 1 y ear, with an incidence rate of tardive dyskinesia (2.6%) one-tenth of that seen with conventional antipsychotics. Risperidone, administered at a low d osage of 1 mg/day was associated with fewer extrapyramidal symptoms compare d with haloperidol in elderly patients, Risperidone was well tolerated with no clinically relevant abnormalities in laboratory tests. vital signs or e lectrocardiogram results. Conclusion: The efficacy of risperidone has been demonstrated in the treatm ent of the behavioural and psychological symptoms associated with dementia in the elderly. Preliminary results from 1-year extension studies confirm t he favourable efficacy and tolerability profile of risperidone 1 mg/day, Al though head to head studies with other atypical antipsychotic agents are re quired and the long term use of the drug requires clarification, risperidon e represents a generally well tolerated and effective treatment in the mana gement of dementia-associated behavioural and psychological symptoms in the elderly.