Aripiprazole and quetiapine are the two most recent second generation antipsychotics available in the UK. We aimed to study patients who were prescribed aripiprazole and quetiapine in routine clinical practice, to identify and compare patients who had a good clinical response.

From a data set of 22,000 electronic patient records (from 2002 to 2007), we retrospectively identified all secondary care psychiatric patients started on aripiprazole and quetiapine for schizophrenia and other psychotic disorders. We retrospectively assigned a severity and an improvement score of Clinical Global Impression (CGI) to records, to measure the effectiveness of both drugs.

89 patients were newly prescribed aripiprazole and 132 patients prescribed quetiapine, for schizophrenia and other psychotic conditions. Patients on aripiprazole had a lower initial severity of illness, CGI (Severity) 3.9 versus 4.4, p=0.0003. After excluding treatment resistant patients, a CGI (Improvement) score 1-4 (minimally to very much improved) was achieved with aripiprazole in 69% and quetiapine in 71% of patients. There were no statistical differences in overall discontinuation rates (aripiprazole 40%, quetiapine 41.5%). There were differences in mean time to discontinuation, aripiprazole,165 days, quetiapine, 267 days (p=0.017)

This study is an independent comparison of aripiprazole and quetiapine in schizophrenia and psychoses. Both aripiprazole and quetiapine were clinically effective in the majority of patients. CGI improvement scores were similar for both drugs as were overall discontinuation rates. Patients on aripiprazole, however, discontinued earlier than those discontinuing from quetiapine.