Prediction and evaluation criteria in perazine therapy of acute schizophrenics: psychopathological results

Perazine for schizophrenia

BACKGROUND

Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia and is reputed to have a low level of extrapyramidal adverse effects. As far as we are aware, its use is limited to Germany, Poland, the former Yugoslavia and the Netherlands.

OBJECTIVES

To examine the effects of perazine for those with schizophrenia or related psychoses in comparison with placebo, no treatment or other antipsychotic medications.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register, which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile. We searched the references of all included studies for further trials. We contacted pharmaceutical companies and authors of trials. We updated this search on 16th July 2012.

SELECTION CRITERIA

We selected all randomised controlled trials that compared perazine with other treatments for people with schizophrenia or schizophrenia-like psychoses, or both.

DATA COLLECTION AND ANALYSIS

The review authors (SL, BH, BHe) independently inspected the citations and where possible abstracts and ordered papers for re-inspection and quality assessment. We independently extracted data. We calculated the risk ratio (RR) and 95% confidence interval (CI) using a random-effects model. For continuous data, we calculated mean differences (MD). We inspected all data for heterogeneity, assessed trials for risk of bias and created summary of findings tables using GRADE.

MAIN RESULTS

The review now includes seven trials with a total of 479 participants. In only one trial, with 95 participants, perazine appeared superior to 'active placebo' (trimipramine) at five weeks for the outcome of 'no important global improvement' (n = 95, RR 0.43 CI 0.2 to 0.8, low quality evidence), but there was no statistically significant difference in most measures of mental state. Perazine did not induce more general adverse events than placebo but more participants received at least one dose of antiparkinson medication (n = 95, RR 4.50 CI 1.0 to 19.5, very low quality evidence).Six small trials comparing perazine with other antipsychotics, including 384 participants in total, were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible on most occasions. In the six studies, a similar number of participants receiving perazine or comparator antipsychotics (amisulpride, haloperidol, olanzapine, ziprasidone, zotepine) left the studies early (n = 384, RR 0.97 CI 0.68 to 1.38, low quality evidence). The results on efficacy could not be meta-analysed because the authors presented their results in very different ways. No obvious differences in adverse events between perazine and other antipsychotics could be derived from the limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a way that was suitable for use in meta-analysis, but three small comparisons with the second-generation antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n = 111, RR 0.31 CI 0.1 to 1.1), dyskinesia (n = 111, RR 0.47 CI 0.1 to 3.5), parkinsonism (n = 81, RR 1.21 CI 0.5 2.8) or tremor (n = 40, RR 0.80 CI 0.3 to 2.6) with perazine.

AUTHORS' CONCLUSIONS

The number, size and reporting of randomised controlled perazine trials are insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics but this is based on small comparisons. This should be clarified in larger, well-designed trials.

Perazine for schizophrenia

BACKGROUND

Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia and is reputed to have a low level of extrapyramidal adverse effects. As far as we are aware, its use is limited to Germany, Poland, the former Yugoslavia and the Netherlands.

OBJECTIVES

To examine the effects of perazine for those with schizophrenia, and schizophrenia-like psychoses.

SEARCH STRATEGY

We searched the Cochrane Schizophrenia Group's register which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile (last update of the review March 2005). We searched references of all included studies for further trials. We contacted pharmaceutical companies and authors of trials.

SELECTION CRITERIA

We selected all randomised controlled trials that compared perazine with other treatments for people with schizophrenia and/or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We independently (SL, BH) inspected citations and where possible abstracts and ordered papers for re-inspection and quality assessment. We independently extracted data. We excluded data if loss to follow up was greater than 50%. For homogeneous dichotomous data we calculated the Relative Risk (RR), 95% confidence interval (CI) and, where appropriate, the number needed to treat (NNT) on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD). We inspected all data for heterogeneity.

MAIN RESULTS

We included six trials with a total of 288 participants. In only one trial with 95 participants, perazine appeared superior to 'active placebo' (trimipramine) at five weeks for the outcome of 'no important global improvement' (n=95, RR 0.43 CI 0.2 to 0.8, NNT 4 CI 2 to 13), but there was no statistically significant difference in most measures of mental state. Perazine did not induce more general adverse events than placebo, but more participants received at least one dose of antiparkinson medication (n=95, RR 4.50 CI 1.0 to 19.5, NNH 6 CI 4 to 33). Five small trials comparing perazine with other antipsychotics, including in total only 193 participants, were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible in most occasions. A similar number of participants receiving perazine or comparator antipsychotics left the studies early (n=193, RR 0.85, CI 0.5 to 1.4). The results on efficacy were controversial and need further assessment by randomised controlled trials. No obvious differences in adverse events between perazine and other antipsychotics could be derived from the limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a suitable way for use in meta-analysis, but three small comparisons with the atypical antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n=111, RR 0.31 CI 0.1 to 1.1), dyskinesia (n=111, RR 0.47 CI 0.1 to 3.5), parkinsonism (n=81, RR 1.21 CI 0.5 2.8) or tremor (n=40, RR 0.80 CI 0.3 to 2.6) with perazine.

AUTHORS' CONCLUSIONS

The number, size and reporting of randomised controlled perazine trials is insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics, and this should be clarified in larger, well-designed trials.

Perazine for schizophrenia

BACKGROUND

Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia which has a reputed low level of extrapyramidal side-effects. However, its use is restricted in the sense that - to the best knowledge of the reviewers - it is only marketed in Germany, Poland, Yugoslavia and the Netherlands.

OBJECTIVES

To examine the effects of perazine for those with schizophrenia, and schizophrenia-like psychoses.

SEARCH STRATEGY

Electronic searches of the Cochrane Schizophrenia Group's register which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile were undertaken. References of all included studies were searched for further trials. Pharmaceutical companies and authors of trials were contacted.

SELECTION CRITERIA

All randomised controlled trials that compared perazine with other treatments for people with schizophrenia and/or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

Citations and, where possible, abstracts were independently inspected by two reviewers, papers ordered, re-inspected and quality assessed. Data were independently extracted. Data were excluded if loss to follow up was greater than 50%. For homogeneous dichotomous data the Relative Risk (RR), 95% confidence interval (CI) and, where appropriate, the number needed to treat (NNT) were calculated on an intention-to-treat basis. For continuous data, weighted mean differences were calculated (WMD). All data were inspected for heterogeneity.

MAIN RESULTS

Six trials with a total of 288 participants are included. According to only one trial with 95 participants perazine appeared superior to active placebo (trimipramine) at five weeks for the outcome of 'no important global improvement' (n=95, RR 0.6, CI 0.3-0.9, NNT 4, CI 2-17), but there was no difference in various measures of mental state. The side-effect risk of perazine compared to placebo could not be estimated because they were not reported. Five small trials including only 193 participants which compared perazine with other antipsychotics were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible in most occasions. A similar number of participants receiving perazine or comparator antipsychotics left the studies early (n=193, RR 0.9, CI 0.5-1.4). The results on efficacy were controversial and need further assessment by randomised controlled trials. No obvious differences in adverse events between perazine and other antipsychotics could be derived from these limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a way usable for meta-analysis, but three small comparisons with the atypical antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n=111, RR 0.3, CI 0.1-1.1), dyskinesia (n=111, RR 0.5, CI 0.1-3.5), parkinsonism (n=81, RR 1.2, CI 0.5-2.8) or tremor (n=40, RR 0.8, CI 0.3-2.3) with perazine.

REVIEWER'S CONCLUSIONS

The number, size and reporting of randomised controlled perazine trials is insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics, and this should be clarified in larger, well-designed trials.