Abstract
Background. Despite emerging recognition that off-label use of atypical antipsychotics is widespread, there is little data concerning patterns of such use. To investigate such usage of quetiapine, we evaluated prescribing practices of this drug at our acute-care psychiatric hospital.
Methods. Inpatient orders for quetiapine were obtained from October 2004 to March 2006 and divided into standing or prn (as needed) dose regimens. For patients receiving standing dose regimens, diagnosis, total daily dose, and dosing adequacy were ascertained. For patients receiving prn dosing, diagnosis, behavioral indication, dose, and frequency were determined.
Results. The most common diagnoses in patients receiving standing dose quetiapine were depressive disorders, followed by substance-related, bipolar, and psychotic disorders. Mean dose was 169 ± 154 mg/day (median = 200 mg/day), with 29.8% of patients receiving ≥ 300 mg/day. Only 28.5% of patients had one of the diagnoses for which quetiapine is approved; in these patients, 46.4% received ≥ 300 mg/day. Patients receiving prn dosing had a similar distribution of diagnoses. The most common prn dose was 50 mg, given for agitation or insomnia.
Conclusion. We found extensive off-label use of quetiapine. Further research is needed on the safety and efficacy of quetiapine in non-approved doses and diagnoses.