Risperidone long acting injection: Findings of a 2-year retrospective follow-up study

Objective. The aim of this retrospective study was to assess the clinical effectiveness of risperidone long acting injection (RLAI) at 2 years within an acute mental health setting. Method. All patients who received RLAI between July 2002 and December 2004 were identified from pharmacy records, and data collected by retrospective case note review. In order to give an indication that their condition was unresponsive to treatment, patients' drug histories were reviewed to determine whether or not they had previously been treated with clozapine or received two or more failed trials of other antipsychotic medication. Results. Eighty-four patients were included in the study and 56 discontinued at 2 years. The most common reason for treatment discontinuation was lack of effectiveness, accounting for 32 patients, whilst eight patients discontinued due to adverse effects. Patients remaining on treatment spent 67% of the time in an outpatient setting. Conclusion. The proportion of patients remaining on RLAI at 2 years was 33%. Limitations of the naturalistic methodology used in this study hindered any precise determination of which patients were likely to continue RLAI. However, it was apparent that a history of previous treatment failure with at least two antipsychotics was associated with RLAI treatment discontinuation.