Effect of switching to atypical antipsychotics on memory in patients with chronic schizophrenia. Different side effect profiles of risperidone and clozapine in 20 outpatients with schizophrenia or schizoaffective disorder: a pilot study. International multisite double-blind trial of the atypical antipsychotics risperidone and olanzapine in 175 elderly patients with chronic schizophrenia. Neuropsychological change in early phase schizophrenia during 12 months of treatment with olanzapine, risperidone, or haloperidol. The Canadian Collaborative Group for research in schizophrenia. A double-blind, controlled study of sertindole versus risperidone in the treatment of moderate-to-severe schizophrenia. A double-blind comparative study of clozapine and risperidone in the management of severe chronic schizophrenia. Quetiapine has equivalent efficacy and superior tolerability to risperidone in the treatment of schizophrenia with predominantly negative symptoms. A randomized double-blind 12-week study of quetiapine, risperidone or fluphenazine on sexual functioning in people with schizophrenia. Olanzapine versus risperidone in the treatment of post-psychotic depression in schizophrenic patients. Amisulpride versus risperidone in the treatment of schizophrenic patients: a double-blind pilot study in Taiwan. Risperidone versus clozapine in the treatment of schizophrenic patients with acute symptoms: a double blind, randomized trial. The effects of clozapine and risperidone on spatial working memory in schizophrenia. Olanzapine vs risperidone in the management of schizophrenia: a randomized double-blind trial in Australia and New Zealand. Double-blind comparison of olanzapine versus risperidone in the treatment of schizophrenia and other psychotic disorders. Risperidone versus clozapine in treatment-resistant schizophrenia: a randomized pilot study. Efficacy and tolerability of ziprasidone versus risperidone in patients with acute exacerbation of schizophrenia or schizoaffective disorder: an 8-week, double-blind, multicenter trial. Efficacy of risperidone versus olanzapine in patients with schizophrenia previously on chronic conventional antipsychotic therapy: a switch study. Efficacy and safety of aripiprazole in the acute treatment of schizophrenia in Chinese patients with risperidone as an active control: a randomized trial. Clozapine and risperidone in chronic schizophrenia: effects on symptoms, parkinsonian side effects, and neuroendocrine response. Efficacy and tolerability of olanzapine, quetiapine, and risperidone in the treatment of early psychosis: a randomized, double-blind 52-week comparison. Effectiveness of clozapine versus olanzapine, quetiapine, and risperidone in patients with chronic schizophrenia who did not respond to prior atypical antipsychotic treatment. A randomized double-blind study of risperidone and olanzapine in the treatment of schizophrenia or schizoaffective disorder. Risperidone versus clozapine in treatment-resistant chronic schizophrenia: a randomized double-blind study. The Risperidone Study Group. Clozapine, olanzapine, risperidone, and haloperidol in the treatment of patients with chronic schizophrenia and schizoaffective disorder. Serum leptin and triglyceride levels in patients on treatment with atypical antipsychotics. Effectiveness of olanzapine, quetiapine, risperidone, and ziprasidone in patients with chronic schizophrenia following discontinuation of a previous atypical antipsychotic. A pilot study of risperidone, olanzapine, and haloperidol in psychotic youth: a double-blind, randomized, 8-week trial. Effects of olanzapine, risperidone and haloperidol on prepulse inhibition in schizophrenia patients: a double-blind, randomized controlled trial. A double-blind comparison of risperidone, quetiapine and placebo in patients with schizophrenia experiencing an acute exacerbation requiring hospitalization. Amisulpride vs. risperidone in chronic schizophrenia: results of a 6-month double-blind study. Aripiprazole, an antipsychotic with a novel mechanism of action, and risperidone vs placebo in patients with schizophrenia and schizoaffective disorder. Randomized comparison of olanzapine versus risperidone for the treatment of first-episode schizophrenia: 4-month outcomes. Comparison of quetiapine and risperidone in the treatment of schizophrenia: A randomized, double-blind, flexible-dose, 8-week study.
While the usefulness of atypical antipsychotics for improving cognitive function has been proven, the specific effects of these drugs are still unknown. The objective of this study was to investigate changes of the immediate memory and verbal working memory in patients with chronic schizophrenia after switching to one of four atypical antipsychotic agents and cessation of anticholinergic therapy. The subjects included 77 schizophrenic patients who were treated primarily with typical antipsychotics. Treatment was randomly switched to one of four atypical antipsychotics (olanzapine, perospirone, quetiapine, or risperidone) over a 4-week period, and then the drug was continued for another 4 weeks while the patient was taken off anticholinergics. The immediate memory, verbal working memory, and symptoms were evaluated. Significant improvement of immediate memory was only seen with olanzapine and risperidone. Improvement was also seen after switching to perospirone, but immediate memory worsened after treatment with this anticholinergic drug was discontinued. Deterioration was seen after switching to quetiapine, but immediate memory improved and reached the previous level after treatment with anticholinergic drugs was discontinued. Significant improvement of the verbal working memory was only seen during risperidone administration. The findings suggested that switching chronic schizophrenic patients to atypical antipsychotics can improve both the immediate memory and the verbal working memory when risperidone is used, while improvement of immediate memory can be expected with olanzapine. From the viewpoint of improving the memory, quetiapine should not be administered concomitantly with anticholinergic drugs, and caution should be exercised when discontinuing anticholinergic drugs during treatment with perospirone. The purpose of this study was to compare the side effect +profiles of clozapine and risperidone.
                The subjects were 20 outpatients with schizophrenia or schizoaffective disorder who were clinically stable on a regimen of clozapine at the time of screening. They underwent a randomized-order crossover comparison of 6 weeks of risperidone treatment and 6 weeks of clozapine treatment. Clinical and neurocognitive variables were assessed by raters blind to medication status, and severity of side effects was determined from patients' self-reports.
                Side effect measures, but not clinical ratings, were significantly different after 6 weeks of treatment with the two drugs. Patients required more benztropine for motor effects and complained of more insomnia with risperidone and more sedation with clozapine. Body weight was higher at the end of clozapine treatment than at the end of risperidone treatment.
                In this exploratory study, the side effect profiles of clozapine and risperidone were consistent with the different pharmacodynamic profiles of the two drugs. The authors compared the effects of the two most commonly used atypical antipsychotics, risperidone and olanzapine, in elderly patients with schizophrenia.
                In an 8-week, international, double-blind study, patients (outpatients, hospital inpatients, and residents of nursing or boarding homes) were randomly assigned to receive risperidone (1 mg to 3 mg/day) or olanzapine (5 mg to 20 mg/day). The main outcome measures were changes in Positive and Negative Syndrome Scale (PANSS) total scores and rates of extrapyramidal symptoms (EPS).
                Subjects were 175 patients age 60 years or over with schizophrenia or schizoaffective disorder. The mean duration of illness was 36.5 years. Median doses were 2 mg/day of risperidone and 10 mg/day of olanzapine. PANSS total scores and four of the five PANSS factor scores (positive symptoms, negative symptoms, disorganized thoughts, and anxiety/depression) improved significantly at all time-points and at endpoint in both groups; between-treatment differences were not significant. EPS-related adverse events were reported by 9.2% of patients in the risperidone group and 15.9% in the olanzapine group; the between-treatment difference was not significant. Total scores on the Extrapyramidal Symptom Rating Scale were reduced in both groups at endpoint; between-treatment differences were not significant. Clinically relevant weight gain was seen in both groups, but was significantly less frequent in risperidone patients than in olanzapine patients.
                Stable elderly patients with chronic schizophrenia receiving appropriate doses of risperidone or olanzapine over an 8-week period experienced significant reductions in the severity of psychotic and extrapyramidal symptoms, with a relatively low risk of side effects. The purpose of this investigation was to test the efficacy of novel antipsychotic medications in the treatment of cognitive impairment in early phase schizophrenia.
                Sixty-five patients in this multicenter double-blind study were randomly assigned to olanzapine (5-20 mg), risperidone (4-10 mg), or haloperidol (5-20 mg). Standard measures of clinical and motor syndromes were administered, as well as a comprehensive battery of tests to assess (1) motor skills, (2) attention span, (3) verbal fluency and reasoning, (4) nonverbal fluency and construction, (5) executive skills, and (6) immediate recall at baseline and after 6, 30, and 54 weeks of treatment.
                The general cognitive index derived from the 6 domain scores revealed a significantly greater benefit from treatment with olanzapine relative to haloperidol and olanzapine relative to risperidone, but no significant difference was shown between risperidone and haloperidol. The improvement related to olanzapine was apparent after 6 weeks and enhanced after 30 and 54 weeks of treatment. Exploratory within-group analyses of the 6 cognitive domains after a conservative Bonferroni adjustment revealed a significant improvement with olanzapine only on the immediate recall domain, and similar analyses of the 17 individual tests revealed a significant improvement with olanzapine only on the Hooper Visual Organization Test.
                These data suggest that olanzapine has some superior cognitive benefits relative to haloperidol and risperidone. A larger sample replication study is necessary to confirm and generalize the observations of this study and begin evaluation of the implications of this change to cerebral function and quality of life for people with schizophrenia. Sertindole is a non-sedating atypical antipsychotic effective in the management of schizophrenia and is associated with placebo-level incidence of extrapyramidal symptoms (EPS). In this randomized, double-blind, parallel-group, flexible-dose, multi-centre study, the efficacy and tolerability of sertindole was directly compared with another atypical antipsychotic in patients with schizophrenia. A total of 187 patients were randomly assigned to treatment with sertindole (12-24 mg/day, n=98) or risperidone (4-10 mg/day, n=89) for 12 weeks. Although early termination reduced the power of the study, some significant between-group differences were evident. Sertindole reduced the mean Positive and Negative Syndrome Scale total scores to a greater extent than risperidone, and the difference reached statistical significance at endpoint for the Observed Cases (OC) dataset. Moreover, sertindole was superior for the treatment of negative symptoms compared to risperidone (P<0.05, Last Observation Carried Forward and OC). Both treatment groups were similarly effective in improving Clinical Global Impression (Severity and Improvement), the Drug Attitude Inventory and Global Assessment of Functioning scores. Sertindole and risperidone were both well tolerated. Numerically, fewer patients in the sertindole group (19%) reported EPS-related adverse events than in the risperidone group (28%), although significantly more sertindole-treated patients reported QT prolongation and abnormal ejaculation volume (P<0.05). In conclusion, sertindole was well tolerated and demonstrated clinically relevant efficacy advantages over risperidone. This prospective, double-blind, multicenter, parallel-group study compared the efficacy and safety of therapeutic doses of clozapine and risperidone in patients with severe chronic schizophrenia and poor previous treatment response.
                Male or female patients aged 18-65 years who met DSM-IV criteria for schizophrenia and study requirements for poor previous treatment response (N=273) were randomly assigned to double-blind treatment with either clozapine or risperidone administered over 12 weeks in increasing increments. The primary efficacy measures were the magnitude of improvement in Brief Psychiatric Rating Scale (BPRS) and Clinical Global Impression (CGI) scores. Adverse events were recorded throughout the study.
                The magnitude of improvement in mean BPRS and CGI scores from baseline to end of the study was significantly greater in the clozapine group than in the risperidone group. Statistically significant differences in favor of clozapine were also seen for most of the secondary efficacy measures (Positive and Negative Syndrome Scale, Calgary Depression Scale, Psychotic Depression Scale, and Psychotic Anxiety Scale). The adverse event profile was similar for both treatment groups, with a lower risk of extrapyramidal symptoms in the clozapine group.
                Clozapine showed superior efficacy over risperidone in this patient population. Both treatments were equally well tolerated as demonstrated through their adverse event profiles, although as expected clozapine was associated with a lower risk of extrapyramidal symptoms than risperidone. Atypical antipsychotics are generally thought to be more effective than conventional agents in treating the negative symptoms of schizophrenia; however, there have been few direct comparisons among atypicals. We therefore investigated risperidone and quetiapine with respect to their efficacy against negative symptoms in a 12-week,double-blind, comparative pilot study involving 44 patients with schizophrenia with predominantly negative symptoms, as defined by Positive and Negative Syndrome Scale (PANSS) scores. Other efficacy measures included the Scale for the Assessment of Negative Symptoms (SANS) and the Clinical Global Impression (CGI) rating scale. Antipsychotic tolerability was assessed using the Simpson-Angus Scale (SAS) and various laboratory measures. Mean doses were 589.7 mg/ day quetiapine and 4.9 mg/day risperidone (observed cases). Both antipsychotics produced significant decreases in PANSS total, positive and negative scores, and SANS scores. Patients receiving risperidone were significantly more likely to experience extrapyramidal symptoms (EPS) [p <0.05], or to require anticholinergic medication (p <0.05), and had significantly higher prolactin levels (p <0.001) than quetiapine-treated patients. In conclusion, there is no significant difference in efficacy between quetiapine and risperidone in alleviating the negative symptoms of schizophrenia. Quetiapine is also well tolerated, with a lower incidence of EPS and prolactin increase than risperidone. Sexual dysfunction is common in people suffering from schizophrenia and is reported by patients to be a significant reason for medication nonadherence. This report contains data for 27 people with schizophrenia who participated in a randomized double-blind 12-week trial of risperidone (4 mg/day), quetiapine (400 mg/day) or fluphenazine (12.5 mg/day). At baseline and endpoint, subjects were rated on the Changes in Sexual Function Questionnaire (CSFQ), the Prolactin-Related Adverse Event Questionnaire (PRAEQ) and had prolactin levels drawn. Endpoint prolactin levels were 50.6 +/- 40.4, 24.4 +/- 18.5, and 8.2 +/- 4.4 mg/dl for risperidone (N = 12), fluphenazine (N = 9) and quetiapine (N=6), respectively (F = 7.5,df = 2, p = 0.005, controlling for sex). Orgasm quality/ability improved significantly for quetiapine as compared to fluphenazine and risperidone (F = 4.41, df = 2, p = 0.033). Seventy-eight percent of patients on fluphenazine reported sexual dysfunction whereas did only 42 and 50% of those on risperidone and quetiapine. Forty percent of quetiapine patients reported they felt better about their sexuality as compared to previous treatment, as did 55% on risperidone. Conversely, only 13% of fluphenazine subjects reported any improvement. Hormonal problems (menstrual problems, gynecomastia, galactorrhea) were predominately observed in risperidone-treated subjects. Overall, quetiapine was associated with a normalization of prolactin levels and had the greatest benefits among these drugs regarding sexual functioning. To compare the efficacy of two atypical antipsychotic drugs, olanzapine and risperidone, in schizophrenic patients with post-psychotic depression.
                A clinically significant decrease of MADRS scores occurred in patients treated with both drugs for 8 weeks.
                Atypical antipsychotic drugs may be particularly appropriate when treating schizophrenic patients with depression. The atypical antipsychotics, amisulpride and risperidone, have different receptor affinity characteristics. Although the relative efficacy of both drugs compared to conventional antipsychotics is well established, it remains unclear how the efficacy of amisulpride compares with risperidone. There have been no controlled studies comparing amisulpride to risperidone in Asian patients. The purpose of this study was to compare the efficacy and safety of amisulpride with that of risperidone in Taiwanese schizophrenic patients.
                Patients with productive positive symptoms (n = 48) were enrolled into this double-blind, randomized pilot study for 6 weeks. Patients received either amisulpride (400-800 mg/day) or risperidone (4-8 mg/day). Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression (CGI), Social and Occupational Functioning Assessment Scale (SOFAS), and patients' subjective responses to treatment were assessed during the trial period. Adverse events were recorded at each follow-up visit.
                At the end of the trial, the mean dosage was 630 +/- 134 mg/day and 6.88 +/- 1.54 mg/day for amisulpride and risperidone, respectively. There was no significant difference in the reduction of the PANSS total score (amisulpride -24.1 versus risperidone -28.4, p = 0.999), the PANSS positive subscale score (amisulpride -6.8 versus risperidone -8.3, p = 0.467), the PANSS negative subscale score (amisulpride -5.6 versus risperidone -6.4, p = 0.999), or the CGI score between the two groups. The extrapyramidal symptom ratings, the improvement in the SOFAS (amisulpride 11.1 versus risperidone 10.0) and the subjective response (amisulpride 82% versus risperidone 83%) were comparable. No serious adverse events were recorded in either treatment group. There was a statistically significant body weight gain in the risperidone group. In contrast, there was a statistically, though not clinically, significant reduction of blood pressure and heart rate in the amisulpride group.
                This study suggests that amisulpride is as effective as risperidone in the treatment of patients with schizophrenia. Both drugs were well tolerated, but had different side effect profiles. 1. In order to verify the hypothesis that risperidone is a useful therapeutic alternative to clozapine the authors carried out a randomized double blind trial in 59 patients with paranoid hallucinatory psychoses. 2. In a treatment lasting 28 days three groups of patients received either 4 mg risperidone (N = 20), 8 mg risperidone (N = 19), or 400 mg clozapine (N = 20) daily. 3. The tolerance of 4 mg risperidone was globally assessed as being better than that of 400 mg clozapine. Drop-outs under clozapine were mostly caused by side effects, whereas under risperidone they tended to occur for therapeutic inefficacy. 4. The antipsychotic effect was highly significant and clinically relevant under both risperidone and clozapine. The purpose of this investigation was to evaluate the effects of clozapine and risperidone on spatial working memory in patients with schizophrenia.
                Spatial working memory performance was evaluated at baseline and after 17 and 29 weeks in 97 patients with schizophrenia participating in a multisite trial.
                Compared with baseline performance while receiving conventional antipsychotic medication, risperidone improved, and clozapine worsened, spatial working memory performance.
                The differential effects of these medications on spatial working memory may be due to the anticholinergic effects of clozapine and prefrontal dopamine-enhancing effects of risperidone. Improved drug therapy for schizophrenia may represent the best strategy for reducing the costs of schizophrenia and the recurrent chronic course of the disease. Olanzapine and risperidone are atypical antipsychotic agents developed to meet this need. We report a multicenter, double-blind, parallel, 30-week study designed to compare the efficacy, safety, and associated resource use for olanzapine and risperidone in Australia and New Zealand. The study sample consisted of 65 patients who met DSM-IV criteria for schizophrenia, schizoaffective disorder, or schizophreniform disorder. Olanzapine-treated patients showed a significantly greater reduction in Positive and Negative Syndrome Scale (PANSS) total, Brief Psychiatric Rating Scale (BPRS) total, and PANSS General Psychopathology scores at endpoint compared to the risperidone-treated patients. Response rates through 30 weeks showed a significantly greater proportion of olanzapine-treated patients had achieved a 20% or greater improvement in their PANSS total score compared to risperidone-treated patients. Olanzapine and risperidone were equivalent in their improvement of PANSS positive and negative scores and Clinical Global Impression-Severity of Illness scale (CGI-S) at endpoint. Using generic and disease-specific measures of quality of life, olanzapine-treated patients showed significant within-group improvement in most measures, and significant differences were observed in favor of olanzapine over risperidone in Quality of Life Scale (QLS) Intrapsychic Foundation and Medical Outcomes Study Short Form 36-item instrument (SF-36) Role Functioning Limitations-Emotional subscale scores. Despite the relatively small sample size, our study suggests that olanzapine has a superior risk:benefit profile compared to risperidone. Olanzapine and risperidone, both second-generation antipsychotic agents, represent two different pharmacologic strategies. Although they share some in vitro properties, they differ by virtue of their chemical structure, spectrum of receptor binding affinities, animal neuropharmacology, pharmacokinetics, and in vivo neuroimaging profile. Based on such differences, it was hypothesized that the two compounds would show distinct safety and/or efficacy characteristics. To test this hypothesis, an international, multicenter, double-blind, parallel-group, 28-week prospective study was conducted with 339 patients who met DSM-IV criteria for schizophrenia, schizophreniform disorder, or schizoaffective disorder. Results of the study indicated that both olanzapine and risperidone were safe and effective in the management of psychotic symptoms. However, olanzapine demonstrated significantly greater efficacy in negative symptoms (Scale for Assessment of Negative Symptoms summary score), as well as overall response rate (> or = 40% decrease in the Positive and Negative Syndrome Scale total score). Furthermore, a statistically significantly greater proportion of the olanzapine-treated than risperidone-treated patients maintained their response at 28 weeks based on Kaplan-Meier survival curves. The incidence of extrapyramidal side effects, hyperprolactinemia, and sexual dysfunction was statistically significantly lower in olanzapine-treated than risperidone-treated patients. In addition, statistically significantly fewer adverse events were reported by olanzapine-treated patients than by their risperidone-treated counterparts. Thus, the differential preclinical profiles of these two drugs were also evident in a controlled, clinical investigation. Olanzapine seemed to have a risk-versus-benefit advantage. 1. The atypical antipsychotic risperidone may constitute an alternative to clozapine, the current treatment of choice for refractory schizophrenia. The objectives of this study were to evaluate the effectiveness of risperidone in comparison to clozapine in everyday practice and to assess the feasibility of a pragmatic trial procedure. 2. Patients were randomly assigned to open-label clozapine or risperidone treatment for 10 weeks and treatment outcomes were assessed blindly. Twenty-one patients were recruited and nineteen entered the randomized phase. 3. Five of 10 participants allocated to clozapine and one of nine risperidone participants dropped out before study completion. Five clozapine patients and six risperidone patients achieved clinical improvement, defined as a 20% decrease in the Positive and Negative Symptom Scale (PANSS) total score. No significant differences between the groups were detected in baseline or endpoint positive or negative symptoms, disease severity, or global or social functioning scores. Patients' opinion on the drugs did not differ between groups. 4. The findings of the intention-to-treat analysis of this study corroborates previous findings that risperidone may be equally effective as clozapine, and supports the feasibility and need of a multicenter randomized pragmatic trial with sufficient power to detect differences between treatments. More head-to-head comparisons of antipsychotics are needed to discern the relative efficacy and safety profiles of these compounds. Thus, we compared ziprasidone and risperidone in patients with acute exacerbation of schizophrenia or schizoaffective disorder.
                Patients with DSM-III-R acute exacerbation of schizophrenia or schizoaffective disorder were randomly assigned to double-blind ziprasidone 40 to 80 mg b.i.d. (N = 149) or risperidone 3 to 5 mg b.i.d (N = 147) for 8 weeks. Primary efficacy measures included Positive and Negative Syndrome Scale (PANSS) total score and Clinical Global Impressions-Severity of Illness scale (CGI-S) score; secondary measures included scores on the PANSS negative sub-scale, CGI-Improvement scale (CGI-I), and PANSS-derived Brief Psychiatric Rating Scale (BPRSd) total and core items. Safety assessments included movement disorder evaluations, laboratory tests, electrocardiography, vital signs, and body weight. Efficacy analyses employed a prospectively defined Evaluable Patients cohort. Treatment equivalence was conferred if the lower limit of the 95% confidence interval of the ziprasidone/risperidone ratio of least-squares mean change from baseline was > 0.60. Data were gathered from August 1995 to January 1997.
                Equivalence was demonstrated in PANSS total scores, CGI-S scores, PANSS negative subscale scores, BPRSd total and core item scores, and PANSS total and CGI-I responder rates. Both agents were well tolerated. Risperidone exhibited a significantly higher Movement Disorder Burden (MDB) score (p < .05) and higher incidences of prolactin elevation and clinically relevant weight gain. However, compared with current recommendations, study dosing may have been high for some risperidone-treated patients (mean dose = 7.4 mg/day) and low for some ziprasidone-treated patients (mean dose = 114.2 mg/day).
                Both agents equally improved psychotic symptoms, and both were generally well tolerated, with ziprasidone demonstrating a lower MDB score and less effect on prolactin and weight than risperidone. The objective of the study was to examine whether patients with schizophrenia who were judged to be stable on long-term treatment with conventional antipsychotic medications would further benefit from a switch to an atypical antipsychotic drug. Thirty-six subjects with schizophrenia spectrum disorder, on conventional antipsychotic medication therapy for at least 2 years, were randomized in double-blind fashion to risperidone versus olanzapine. Patients were titrated up to 6 mg risperidone or 15 mg olanzapine as tolerated, followed by tapering and discontinuation of conventional antipsychotic medication. Atypical antipsychotic agents were then administered alone (monotherapy) for 12 weeks. Efficacy and tolerability were assessed using the Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression Scale, and Simpson Angus Scale. Body weight was measured at each visit. Both treatment groups exhibited marked and similar improvement in the total PANSS score from baseline to study endpoint (22 weeks) [risperidone: baseline=59.3 (SE 3.1), 22 weeks=44.3 (SE 2.3) (p<0.001); olanzapine: baseline=55.9 (SE 3.3), 22 weeks=46.9 (SE 3.2) (p<0.001). Both groups also exhibited significant reductions in PANSS factor scores for positive and negative symptoms and disorganized thoughts. Only risperidone-treated patients exhibited significant decreases in uncontrolled hostility/excitement and anxiety and depression. Of note, while positive factor scores exhibited the majority of change within the first 10 weeks, negative factor scores continued to decline significantly in both treatment groups throughout the study. Tolerability assessments did not differ between groups. The results indicate that both atypical antipsychotic medications provided significant additional improvement in symptom severity in patients with schizophrenia previously on conventional antipsychotic agents. Asian populations may differ from other races in response to antipsychotics. Studies of aripiprazole in Asian populations are scarce. This study aimed to investigate the efficacy, safety, and tolerability of aripiprazole in Chinese patients with acute schizophrenia or schizoaffective disorder.
                This 4-week, double-blind, randomized, parallel study was conducted in 5 medical centers in Taiwan between March 2004 and January 2005. A total of 83 patients with a primary DSM-IV diagnosis of schizophrenia or schizoaffective disorder were randomly assigned (with a randomization ratio of 3:2) to 15 mg/day of aripiprazole (N = 49) or 6 mg/day of risperidone (N = 34). Efficacy measures included the Positive and Negative Syndrome Scale (PANSS) total, positive, and negative scores and Clinical Global Impressions-Severity of Illness (CGI-S) and -Improvement scale scores. Extrapyramidal symptoms (EPS), weight gain, serum prolactin level, QTc interval, and self-reported adverse events were assessed as measures of safety and tolerability.
                Both the aripiprazole and risperidone groups showed statistical improvement from baseline in PANSS total, PANSS positive, PANSS negative, and CGI-S scores at study endpoint (all p < .001). Significant improvement was noted in the first week of treatment for both treatment groups. There were no significant differences in efficacy measures between treatment groups. Aripiprazole showed significantly less EPS liability as assessed by the Simpson-Angus Scale (p < .005) and less serum prolactin level elevation (p < .001) than risperidone. Both groups showed mild weight gain. No patients showed clinically significant QTc interval prolongation in this study.
                Compared with risperidone 6 mg/day, aripiprazole 15 mg/day has comparable efficacy and favorable safety and tolerability profiles in the short-term treatment of Chinese patients with acute schizophrenia. In this group of Chinese patients, the overall response to aripiprazole did not differ from that of white patients.
                ClinicalTrials.gov identifier NCT00283179. Clozapine and risperidone were the first two "second-generation" antipsychotic drugs approved for schizophrenia. There is currently little information about their comparative efficacy from head-to-head clinical trials. The purpose of this study was to examine the comparative efficacy of clozapine and risperidone for positive and negative symptoms, depression, parkinsonian side effects, and indexes of neuroendocrine function in schizophrenic patients who met a priori criteria for partial response to traditional neuroleptic agents.
                After a baseline fluphenazine treatment period, 29 patients participated in a 6-week, double-blind, parallel-group comparison of the effects of these agents.
                Clozapine was superior to risperidone for positive symptoms and parkinsonian side effects, but there were no significant differences between the drugs on two measures of negative symptoms, Brief Psychiatric Rating Scale total scores, and depression scores. The clozapine patients, but not the risperidone patients, demonstrated significant reductions from the fluphenazine baseline in positive symptoms, total symptoms, and depression. In addition, clozapine produced fewer effects on plasma prolactin than risperidone or fluphenazine. The mean daily doses during week 6 of the trial were 403.6 mg of clozapine and 5.9 mg of risperidone.
                The findings from this study indicate that these drugs have both important differences and similarities in their comparative efficacy in chronically ill, partially responsive patients with schizophrenia. Further research on second-generation antipsychotic drugs in this patient population that addresses key methodological issues, such as optimal dose and treatment duration, are needed. This 52-week randomized, double-blind, flexible-dose, multicenter study evaluated the overall effectiveness (as measured by treatment discontinuation rates) of olanzapine, quetiapine, and risperidone in patients early in the course of psychotic illness.
                Patients were randomly assigned to treatment with olanzapine (2.5-20 mg/day), quetiapine (100-800 mg/day), or risperidone (0.5-4 mg/day) administered in twice-daily doses. Statistical analyses tested for noninferiority in all-cause treatment discontinuation rates up to 52 weeks (primary outcome measure) based on a prespecified noninferiority margin of 20%.
                A total of 400 patients were randomly assigned to treatment with olanzapine (N=133), quetiapine (N=134), or risperidone (N=133). The mean modal prescribed daily doses were 11.7 mg for olanzapine, 506 mg for quetiapine, and 2.4 mg for risperidone. At week 52, all-cause treatment discontinuation rates were 68.4%, 70.9%, and 71.4% for olanzapine, quetiapine, and risperidone, respectively. Reductions in total score on the Positive and Negative Syndrome Scale (PANSS) were similar for the three treatment groups, but reductions in PANSS positive subscale scores were greater in the olanzapine group (at 12 weeks and at 52 weeks or withdrawal from study) and the risperidone group (at 12 weeks). The most common elicited adverse events for olanzapine were drowsiness (53%), weight gain (51%), and insomnia (38%); for quetiapine, drowsiness (58%), increased sleep hours (42%), and weight gain (40%); and for risperidone, drowsiness (50%), menstrual irregularities in women (47%), and weight gain (41%).
                Olanzapine, quetiapine, and risperidone demonstrated comparable effectiveness in early-psychosis patients, as indicated by similar rates of all-cause treatment discontinuation. When a schizophrenia patient has an inadequate response to treatment with an antipsychotic drug, it is unclear what other antipsychotic to switch to and when to use clozapine. In this study, the authors compared switching to clozapine with switching to another atypical antipsychotic in patients who had discontinued treatment with a newer atypical antipsychotic in the context of the Clinical Antipsychotic Trials for Interventions Effectiveness (CATIE) investigation.
                Ninety-nine patients who discontinued treatment with olanzapine, quetiapine, risperidone, or ziprasidone in phase 1 or 1B of the trials, primarily because of inadequate efficacy, were randomly assigned to open-label treatment with clozapine (N=49) or blinded treatment with another newer atypical antipsychotic not previously received in the trial (olanzapine [N=19], quetiapine [N=15], or risperidone [N=16]).
                Time until treatment discontinuation for any reason was significantly longer for clozapine (median=10.5 months) than for quetiapine (median=3.3), or risperidone (median=2.8), but not for olanzapine (median=2.7). Time to discontinuation because of inadequate therapeutic effect was significantly longer for clozapine than for olanzapine, quetiapine, or risperidone. At 3-month assessments, Positive and Negative Syndrome Scale total scores had decreased more in patients treated with clozapine than in patients treated with quetiapine or risperidone but not olanzapine. One patient treated with clozapine developed agranulocytosis, and another developed eosinophilia; both required treatment discontinuation.
                For these patients with schizophrenia who prospectively failed to improve with an atypical antipsychotic, clozapine was more effective than switching to another newer atypical antipsychotic. Safety monitoring is necessary to detect and manage clozapine's serious side effects. The safety and efficacy of risperidone and olanzapine were compared in a double-blind trial that used doses widely accepted in clinical practice.
                Subjects (N=377) who met DSM-IV criteria for schizophrenia or schizoaffective disorder were randomly assigned to receive 2-6 mg/day of risperidone (mean modal dose=4.8 mg/day) or 5-20 mg/day of olanzapine (mean modal dose=12.4 mg/day) for 8 weeks.
                The two study groups were similar at baseline except that the olanzapine group was slightly younger than the risperidone group. Seventy-five percent of the participants completed the trial, with no between-treatment differences in the proportion of dropouts. Similar proportions of the risperidone and olanzapine groups reported extrapyramidal symptoms (24% and 20%, respectively). Severity of extrapyramidal symptoms was low in both groups, with no between-group differences. Total Positive and Negative Syndrome Scale scores and scores on the five Positive and Negative Syndrome Scale factors were improved in both groups at week 8 (subjects who completed the study) and endpoint (all subjects, including dropouts). There were overall between-treatment differences in efficacy. Comparison of individual factors found no significant differences at endpoint; at week 8, however, improvements on Positive and Negative Syndrome Scale factors for positive symptoms and anxiety/depression were greater with risperidone than olanzapine. An increase in body weight of > or =7% was seen in 27% of olanzapine participants and 12% of risperidone participants.
                Both treatments were well tolerated and efficacious. The frequency and severity of extrapyramidal symptoms were similar in the two treatment groups. Greater reductions in severity of positive and affective symptoms were seen with risperidone than with olanzapine treatment among study completers. There was no measure on which olanzapine was superior. Greater weight gain was associated with olanzapine than with risperidone treatment. The purpose of this study was to compare the short-term efficacy and safety of risperidone and clozapine in treatment-resistant chronic schizophrenic patients.
                In a controlled double-blind, multicenter study, 86 inpatients with chronic schizophrenia (DSM-III-R), who were resistant to or intolerant of conventional neuroleptics, were randomly assigned to receive risperidone or clozapine for 8 weeks after a 7-day washout period. After a 1-week dose-titration phase, doses were fixed at 6 mg/day of risperidone and 300 mg/day of clozapine for 1 week and then adjusted according to each patient's response. The final mean doses were 6.4 mg/day of risperidone and 291.2 mg/day of clozapine. Treatment efficacy and safety were evaluated with several well-known rating scales.
                Both risperidone and clozapine significantly reduced the severity of psychotic symptoms (scores on the Positive and Negative Syndrome Scale and the Clinical Global Impression scale) from baseline, with no significant between-group differences. At endpoint, 67% of the risperidone group and 65% of the clozapine group were clinically improved (reduction of 20% or more in total Positive and Negative Syndrome Scale score). Risperidone appeared to have a faster onset of action. In both groups extrapyramidal symptoms and other adverse events were few, and their severity was generally mild. Neither group showed evidence of a relation between drug plasma concentrations and clinical effectiveness.
                Risperidone was well tolerated and as effective as medium doses of clozapine in patients with chronic schizophrenia who had been resistant to or intolerant of conventional neuroleptics. The authors compared the efficacy and safety of three atypical antipsychotics (clozapine, olanzapine, and risperidone) with one another and with haloperidol in the treatment of patients with chronic schizophrenia or schizoaffective disorder.
                In a double-blind trial, 157 inpatients with a history of suboptimal treatment response were randomly assigned to treatment with clozapine, olanzapine, risperidone, or haloperidol for 14 weeks (an 8-week escalation and fixed-dose period followed by a 6-week variable-dose period).
                Clozapine, risperidone, and olanzapine (but not haloperidol) resulted in statistically significant improvements in total score on the Positive and Negative Syndrome Scale. Improvements seen in total and negative symptom scores with clozapine and olanzapine were superior to haloperidol. The atypical drugs, particularly olanzapine and clozapine, were associated with weight gain.
                The effects of atypical antipsychotics in this population were statistically significant but clinically modest. The overall pattern of results suggests that clozapine and olanzapine have similar general antipsychotic efficacy and that risperidone may be somewhat less effective. Clozapine was the most effective treatment for negative symptoms. However, the differences among treatments were small. Weight gain is a common adverse effect associated with the use of most antipsychotic drugs. Leptin has been reported to be associated with antipsychotic-induced weight gain. Previous studies have demonstrated a relationship between the atypical antipsychotics clozapine and olanzapine and serum leptin levels. We planned to comparatively investigate the effects of the atypical antipsychotics quetiapine, olanzapine, risperidone, and clozapine on leptin and triglyceride levels and weight gain.
                The study population comprised 56 patients with DSM-IV schizophrenia, who were divided into 4 treatment groups: quetiapine (N = 14), olanzapine (N = 14), risperidone (N = 14), or clozapine (N = 14) monotherapy, and a control group of 11 patients receiving no psychopharmacologic treatment. The patients were evaluated at baseline and at the sixth week according to the Positive and Negative Syndrome Scale (PANSS), body mass index (BMI), weight, and fasting serum leptin and triglyceride levels. Data were gathered in 2001 and 2002.
                Olanzapine and clozapine caused a marked increase in weight and serum triglyceride and leptin levels, though increases in these variables were modest in the patients receiving quetiapine and minimal in those receiving risperidone. There were positive correlations between serum leptin levels and BMI and triglyceride levels. Clinical efficacy, as indicated by decrease in total PANSS scores, was associated with leptin levels in all atypical antipsychotic groups.
                Our results suggest that leptin may be associated with olanzapine- and clozapine-induced weight gain and that quetiapine appears to have modest influence and risperidone appears to have minimal influence on leptin and triglyceride levels and weight gain compared with olanzapine and clozapine. In the treatment of schizophrenia, changing antipsychotics is common when one treatment is suboptimally effective, but the relative effectiveness of drugs used in this strategy is unknown. This randomized, double-blind study compared olanzapine, quetiapine, risperidone, and ziprasidone in patients who had just discontinued a different atypical antipsychotic.
                Subjects with schizophrenia (N=444) who had discontinued the atypical antipsychotic randomly assigned during phase 1 of the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) investigation were randomly reassigned to double-blind treatment with a different antipsychotic (olanzapine, 7.5-30 mg/day [N=66]; quetiapine, 200-800 mg/day [N=63]; risperidone, 1.5-6.0 mg/day [N=69]; or ziprasidone, 40-160 mg/day [N=135]). The primary aim was to determine if there were differences between these four treatments in effectiveness measured by time until discontinuation for any reason.
                The time to treatment discontinuation was longer for patients treated with risperidone (median: 7.0 months) and olanzapine (6.3 months) than with quetiapine (4.0 months) and ziprasidone (2.8 months). Among patients who discontinued their previous antipsychotic because of inefficacy (N=184), olanzapine was more effective than quetiapine and ziprasidone, and risperidone was more effective than quetiapine. There were no significant differences between antipsychotics among those who discontinued their previous treatment because of intolerability (N=168).
                Among this group of patients with chronic schizophrenia who had just discontinued treatment with an atypical antipsychotic, risperidone and olanzapine were more effective than quetiapine and ziprasidone as reflected by longer time until discontinuation for any reason. This pilot study was undertaken to estimate the acute antipsychotic effect size and side effect propensity of risperidone and olanzapine in the pediatric population, in comparison to haloperidol, a conventional antipsychotic with established efficacy. Risperidone and olanzapine are widely used as first-line treatments to ameliorate psychotic symptoms in youth, but their abilities to specifically treat children and adolescents presenting due to psychotic symptoms have not been rigorously studied. Subjects, selected because of prominent positive psychotic symptoms, were randomly assigned to double-blind, parallel treatment with risperidone, olanzapine, or haloperidol for 8 weeks. The primary outcome was reduction in the Brief Psychiatric Rating Scale for Children total score from baseline to termination. An exploratory, descriptive analysis was done to compare the three treatments. A total of 50 patients, 8-19 years, participated. All treatments reduced symptoms significantly with p-values (corrected for multiple comparisons) of 0.0018 for each of the atypical agents and 0.012 for haloperidol. In all, 88% of subjects treated with olanzapine, 74% treated with risperidone, and 53% treated with haloperidol met response criteria. The primary side effects observed in all patients were mild to moderate sedation, extrapyramidal symptoms, and weight gain. Risperidone and olanzapine acutely reduced psychotic symptoms in this pediatric sample. Exploratory comparisons indicate the magnitude of the antipsychotic response with these atypical agents is comparable to that observed with haloperidol. However, youth treated with risperidone and olanzapine experienced weight gain and extrapyramidal effects that appear more prevalent and severe than reported in adults. Prepulse inhibition (PPI), whereby the startle eyeblink response is inhibited by a relatively weak non-startling stimulus preceding the powerful startle eliciting stimulus, is a measure of sensorimotor gating and has been shown to be deficient in schizophrenia patients. There is considerable interest in whether conventional and/or atypical antipsychotic medications can "normalize" PPI deficits in schizophrenia patients. 51 schizophrenia patients participated in a randomized, double-blind controlled trial on the effects of three commonly-prescribed antipsychotic medications (risperidone, olanzapine, or haloperidol) on PPI, startle habituation, and startle reactivity. Patients were tested at baseline, Week 4 and Week 8. Mixed model regression analyses revealed that olanzapine significantly improved PPI from Week 4 to Week 8, and that at Week 8 patients receiving olanzapine produced significantly greater PPI than those receiving risperidone, but not haloperidol. There were no effects of medication on startle habituation or startle reactivity. These results support the conclusion that olanzapine effectively increased PPI in schizophrenia patients, but that risperidone and haloperidol had no such effects. The results are discussed in terms of animal models, neural substrates, and treatment implications. This study compared the effects of atypical antipsychotics (risperidone or quetiapine) with placebo and with each other in recently exacerbated patients with schizophrenia requiring hospitalization.
                This international, randomized, double-blind study included a 2-week monotherapy phase followed by a 4-week additive therapy phase. Recently exacerbated patients with schizophrenia or schizoaffective disorder (DSM-IV) were randomized (2:2:1) to risperidone (n = 153), quetiapine (n = 156), or placebo (n = 73). Target doses were 4 or 6 mg/day of risperidone and 400 or 600 mg/day of quetiapine by day 5, with the ability to increase to 600 or 800 mg/day of quetiapine on day 8. The main outcome measures were the total Positive and Negative Syndrome Scale (PANSS) and need for additional psychotropic medications.
                Monotherapy Phase: The combined atypical antipsychotic group (n = 308) reached borderline superiority to placebo (n = 71) at the 2-week endpoint on mean change in total PANSS score (-24.1 +/- 1.2 and -20.2 +/- 2.0, respectively; p = 0.067). The change in the atypical group was driven by the improvement with risperidone (-27.7 +/- 1.5 vs. -20.2 +/- 2.0 with placebo, p < 0.01; and vs. -20.5 +/- 1.5 with quetiapine, p < 0.01); the improvement with quetiapine was similar to placebo, p = 0.879. Results were similar on other efficacy endpoints. Additive Therapy Phase: Additional psychotropics were prescribed to fewer (p < 0.01) risperidone (36%) than quetiapine (53%) or placebo patients (59%). The overall discontinuation rate was 18%, 26%, and 38%, respectively. Risperidone, compared with placebo, was associated with more parkinsonism, akathisia, plasma prolactin changes, and weight gain; while quetiapine was associated with more somnolence, sedation, dizziness, constipation, tachycardia, thyroid dysregulation, and weight gain.
                While the combined atypical antipsychotic group did not experience greater improvements than the placebo group, risperidone, but not quetiapine, was significantly superior in all measured domains to placebo in the management of recently exacerbated hospitalized patients with schizophrenia or schizoaffective disorder, with no unexpected tolerability findings. This multicenter, double-blind, randomized study evaluated the efficacy, safety and functional effects of two atypical antipsychotics, amisulpride and risperidone, in patients with chronic schizophrenia (DSM IV) with a recent worsening of symptoms. It was planned as a non-inferiority trial. 309 patients received amisulpride (400-1,000 mg/day) or risperidone (4-10 mg/day) for six months. Amisulpride was demonstrated to be not inferior to risperidone with respect to the decrease in Positive and Negative Syndrome Scale (PANSS) total score from baseline (90% 2-sided confidence interval (-5.6; 4.0)). Symptomatic improvement measured with the Brief Psychiatry Rating Scale (BPRS), the PANSS positive subscale, and the Bech Rafaelsen Melancholia Scale was similar in both groups. Amisulpride was significantly (p <.05) superior to risperidone in terms of response (>/=50% improvement in PANSS and BPRS total scores or "very much/much improved" on the Clinical Global Impression Scale) and also demonstrated better functional effects and subjective response. Both treatments were well tolerated and had a similar low incidence of extrapyramidal symptoms; however, amisulpride was associated with less weight gain and endocrine/sexual symptoms. Aripiprazole is a dopamine D2 receptor partial agonist with partial agonist activity at serotonin 5HT1A receptors and antagonist activity at 5HT2A receptors. This multicenter trial examined the efficacy, safety, and tolerability of aripiprazole in patients with acute exacerbation of schizophrenia or schizoaffective disorder.
                In this 4-week double-blind study, 404 patients were randomized to 20 mg/d (n = 101) or 30 mg/d (n = 101) of aripiprazole, placebo (n = 103), or 6 mg/d of risperidone (n = 99). Efficacy assessments included Positive and Negative Syndrome Scale (PANSS) scores and Clinical Global Impression scores. Safety and tolerability evaluations included extrapyramidal symptoms and effects on weight, prolactin, and corrected QT (QTc) interval.
                Aripiprazole (20 and 30 mg/d) and risperidone (6 mg/d) were significantly better than placebo on all efficacy measures. Separation from placebo occurred at week 1 for PANSS total and positive scores with aripiprazole and risperidone and for PANSS negative scores with aripiprazole. There were no significant differences between aripiprazole and placebo in mean change from baseline in the extrapyramidal symptom rating scales. Mean prolactin levels decreased with aripiprazole but significantly increased 5-fold with risperidone. Mean change in QTc interval did not differ significantly from placebo with any active treatment group. Aripiprazole and risperidone groups showed a similar low incidence of clinically significant weight gain.
                Aripiprazole is effective, safe, and well tolerated for the positive and negative symptoms in schizophrenia and schizoaffective disorder. It is the first non-D2 receptor antagonist with clear antipsychotic effects and represents a novel treatment development for psychotic disorders. The authors compared 4-month treatment outcomes for olanzapine versus risperidone in patients with first-episode schizophrenia spectrum disorders.
                One hundred twelve subjects (70% male; mean age=23.3 years [SD = 5.1]) with first-episode schizophrenia (75%), schizophreniform disorder (17%), or schizoaffective disorder (8%) were randomly assigned to treatment with olanzapine (2.5-20 mg/day) or risperidone (1-6 mg/day).
                Response rates did not significantly differ between olanzapine (43.7%, 95% CI=28.8%-58.6%) and risperidone (54.3%, 95% CI=39.9%-68.7%). Among those responding to treatment, more subjects in the olanzapine group (40.9%, 95% CI=16.8%-65.0%) than in the risperidone group (18.9%, 95% CI=0%-39.2%) had subsequent ratings not meeting response criteria. Negative symptom outcomes and measures of parkinsonism and akathisia did not differ between medications. Extrapyramidal symptom severity scores were 1.4 (95% CI=1.2-1.6) with risperidone and 1.2 (95% CI=1.0-1.4) with olanzapine. Significantly more weight gain occurred with olanzapine than with risperidone: the increase in weight at 4 months relative to baseline weight was 17.3% (95% CI=14.2%-20.5%) with olanzapine and 11.3% (95% CI=8.4%-14.3%) with risperidone. Body mass index at baseline and at 4 months was 24.3 (95% CI=22.8-25.7) versus 28.2 (95% CI=26.7-29.7) with olanzapine and 23.9 (95% CI=22.5-25.3) versus 26.7 (95% CI=25.2-28.2) with risperidone.
                Clinical outcomes with risperidone were equal to those with olanzapine, and response may be more stable. Olanzapine may have an advantage for motor side effects. Both medications caused substantial rapid weight gain, but weight gain was greater with olanzapine. To compare the efficacy and tolerability of quetiapine and risperidone in the treatment of schizophrenia.
                In this 8-week, double-blind, multicenter, flexible-dose study, patients with schizophrenia (DSM-IV diagnosis) were randomly assigned to quetiapine (200-800 mg/day) or risperidone (2-8 mg/day). The primary hypothesis was that quetiapine was not inferior to risperidone. The primary efficacy measure was change from baseline in Positive and Negative Syndrome Scale (PANSS) total scores; secondary outcomes included response rate (> or = 40% reduction in PANSS scores), Clinical Global Impression-Change (CGI-C), and cognitive and social functioning. Tolerability assessments included treatment-emergent adverse events and changes in weight, glucose, and prolactin. Patients were recruited from June 2001 to September 2002.
                Patients (N = 673) were randomly assigned to quetiapine (N = 338, mean dose = 525 mg/day) or risperidone (N = 335, mean dose = 5.2 mg/day). The primary analysis demonstrated noninferiority between treatments (p < .05). Improvements with both treatments were comparable on PANSS total, negative, and general psychopathology subscales. Risperidone-treated patients had a significantly (p = .03) greater improvement in PANSS positive subscale score among all patients, but not among completers. Improvements in PANSS response rates, CGI-C, and cognitive function were similar between treatment groups. Changes in serum glucose and weight were minimal and comparable. The rate of extrapyramidal symptom (EPS)-related adverse events was significantly higher with risperidone (22%) than quetiapine (13%; p < .01). Somnolence was more common with quetiapine (26%) than risperidone (20%; p = .04). Prolactin levels increased with risperidone (+35.5 ng/mL), but decreased with quetiapine (-11.5 ng/mL; p < .001).
                Quetiapine and risperidone had broadly comparable clinical efficacy. Both agents improved cognitive and social functioning, and neither had a clinically significant effect on weight or glucose. Somnolence was more common with quetiapine; EPS and elevated prolactin rates were significantly higher with risperidone.
Risperidone seems to produce somewhat more extrapyramidal side effects and clearly more prolactin increase than most other SGAs. It may also differ from other compounds in efficacy and in the occurrence of other adverse effects such as weight gain, metabolic problems, cardiac effects, sedation and seizures. Nevertheless, the large proportion of participants leaving studies early and incomplete reporting of outcomes makes it difficult to draw firm conclusions. Further large trials, especially comparing risperidone with those other new drugs for which only a few RCTs are available, are needed.