Quetiapine may not differ from typical antipsychotics in the treatment of positive symptoms and general psychopathology. There are no clear differences in terms of the treatment of negative symptoms. However, it causes fewer adverse effects in terms of abnormal ECG, extrapyramidal effects, abnormal prolactin levels and weight gain.
Risperidone, quetiapine, and fluphenazine in the treatment of patients with therapy-refractory schizophrenia.
This 12-week, double-blind study evaluated the effectiveness of risperidone (4 mg/day), quetiapine (400 mg/day), or fluphenazine (12.5 mg/day) in a stringently defined treatment-resistant population of people with schizophrenia. No differences were noted in total Brief Psychiatric Rating Scale (BPRS) or Clinical Global Impression scores among the drug groups (n = 38). More subjects tended to complete the study on risperidone (69%) or quetiapine (58%) than those treated with fluphenazine (31%; P value not significant). Eighty-nine percent of those who discontinued on fluphenazine (8 of 9) were due to lack of efficacy. Discontinuation due to adverse effects was low, with only 2 subjects (both on quetiapine) stopping due to side effects. Three of 13 risperidone-treated subjects (23%) and 3 of 12 quetiapine-treated subjects (25%) met response criteria (decrease of 20% of total BPRS score), whereas 2 of 13 subjects (15%) responded to fluphenazine. Side effect occurrence was similar among drug groups and EPS ratings on the Simpson Angus Scale improved in all drug groups (quetiapine, 1.64; risperidone, 1.30; fluphenazine, 0.69; P value not significant). Despite the newer class of second-generation antipsychotic medications, this treatment-resistant population remains difficult to treat. Many people have only minimal to modest improvements with antipsychotic treatment and most continue to have residual psychotic symptoms. Treatment with first- and second-generation antipsychotics may demonstrate similar efficacy; however, patients treated with second-generation antipsychotics may be more likely to adhere to treatment.