In clinical practice, it is not always clear which patients will benefit from which antipsychotic. As with other antipsychotics, risperidone long-acting injection (RLAI) has been shown to be effective and well-tolerated in clinical trials. This study examines reasons for discontinuation with RLAI and therefore may help to identify suitable patients in the future to improve treatment success.

Fifteen patients with schizophrenia or schizoaffective disorder were prescribed RLAI with a mean age of 42.7 years. The primary reason for initiating RLAI was non-compliance with previous treatment (n=14). At the time of the audit, 40% of patients (n=6) were continuing treatment. Of the patients who discontinued, five were switched to clozapine for treatment resistance after an average trial of at 11 months with RLAI. (RLAI is not licensed for treatment resistance.) The other four patients who discontinued did not like receiving injections after an average trial of four months.

The patients who continued treatment with RLAI have experienced improvements with a 38.6% decrease in CGI scores (5.7 at baseline to 3.5 at endpoint, n=6). The mean duration of treatment was 15.7 months.

Although retention rates are relatively low in this audit, there are clear reasons for discontinuation. Several patients did not like receiving injections and received only a short trial. Five patients were switched to clozapine from RLAI because of treatment resistance. The rationale for prescribing RLAI prior to clozapine is to eliminate non-compliance with oral medication. Patients who continued on RLAI long-term had good outcomes and RLAI was generally well tolerated.