Evaluating appropriateness of prescribing of long-acting risperidone for injection in acute care settings.

Abstract

Long-acting risperidone for injection is a second-generation antipsychotic indicated for the treatment of schizophrenia and related psychotic disorders. It is a relatively new agent with pharmacokinetic and dosing properties unlike those of conventional long-acting antipsychotic drugs administered by injection. To determine the proportion of patients for whom long-acting risperidone for injection was prescribed appropriately in acute care settings in the Fraser Health Authority of British Columbia, according to the following 4 criteria: approved indication for therapy, 2-week dosing intervals, dose increases no sooner than every 4 weeks, and initial overlap supplementation with another antipsychotic for at least 3 weeks. A variety of other variables, including documented approval under special authority from the provincial drug coverage program, length of hospital stay, initial dose of risperidone, and total number of doses, were assessed as secondary outcomes. A chart review was conducted for all patients for whom therapy with long-acting risperidone for injection was prescribed during stays in 8 acute care hospitals between July 1, 2007, and July 22, 2008. The appropriateness of prescribing was assessed according to the 4 prespecified criteria. Long-acting risperidone for injection was prescribed for 116 patients during the study period, and 82 of these started therapy and were included in the evaluation. The primary outcome could not be assessed for 27 of these 82 patients, because they were discharged early, and data for some or all of the 4 criteria were not available. For 33 (60%) of the 55 remaining patients, long-acting risperidone for injection had been prescribed appropriately. In contrast, for 22 (40%) of the patients, prescription of risperidone was deemed inappropriate because of failure to meet at least 1 of the 4 criteria. Premature escalation of the dose and inadequate overlap with antipsychotic supplementation were the most common reasons for designation of the prescription as inappropriate. Opportunities exist to improve prescribing practices for long-acting risperidone for injection in acute care institutions in this health authority.