Evaluation of Inpatient Depot Antipsychotic Prescribing

OBJECTIVE: To assess the use of fluphenazine decanoate and haloperidol decanoate in an inpatient setting. DESIGN: A prospective observational study conducted over a 3-month period. SETTING: A 400-bed state psychiatric hospital. INTERVENTIONS: The psychiatric pharmacy staff evaluated the medical records and new orders of 30 consecutive patients receiving depot antipsychotic formulations using a detailed evaluation form and the hospital pharmacy computer database. Criteria for evaluation were derived from the medical literature and product information, and included the following areas: diagnosis, stabilization on a short-acting form of the antipsychotic, appropriateness of dosage conversion to depot therapy, concomitant administration of short-acting antipsychotics (and duration of concomitant medications), and plasma concentration monitoring. RESULTS: Only 7 patients (23%) received what would be considered optimal depot antipsychotic therapy. These patients were receiving a stable dosage of a short-acting antipsychotic prior to conversion to depot therapy (i.e., ≥7 d), received optimal dose conversion to a depot form, and received optimum overlap with a short-acting preparation (i.e., overlap ≤7 d with fluphenazine HCl and 7–30 d with haloperidol HCl). When length of stay data were evaluated, no significant differences were observed in patients who received optimal therapy versus those who did not. There was also no difference in length of stay when the study group was compared with an age-, sex-, and diagnosis-matched cohort group. However, quantitatively fewer adverse effects were reported for patients whose treatment was considered optimal on the basis of the evaluation criteria. CONCLUSIONS: Depot antipsychotic therapy frequently did not meet the criteria for optimal use. This did not affect length of hospital stay in these individuals. However, individuals who met the criteria experienced quantitatively fewer adverse events.