Simultaneous prescribing of atypical antipsychotics, conventional antipsychotics and anticholinergics—a European study

OBJECTIVE: The aim of this study was to investigate to what extent atypical antipsychotics, conventional antipsychotics and anticholinergics are prescribed simultaneously in daily clinical practice in Europe. METHOD: A pharmaco-epidemiological study was carried out in which hospital pharmacists from 45 hospitals in Belgium, Denmark, France, Germany, The Netherlands and Scotland participated. Prescription data for 2,725 patients (mainly inpatients) who had been using an atypical antipsychotic for more than 6 weeks were analysed. MAIN OUTCOME MEASURE: The frequencies of simultaneous prescription of atypical antipsychotics with other antipsychotics and/or anticholinergics. RESULTS: In this sample of patients with an atypical antipsychotic 42.1% was prescribed another antipsychotic (24.1% if low-potent antipsychotics were not included in the analysis) and 30.1% was prescribed an anticholinergic. In total 47.1% of patients were prescribed an atypical antipsychotic without any other antipsychotic or anticholinergic. CONCLUSION: It is common practice to prescribe a combination of atypical antipsychotics and conventional antipsychotics and/or anticholinergics. This suggests that monotherapy involving an atypical antipsychotic is not considered to be an adequate treatment for a substantial number of patients in clinical practice.