State of the art of drug treatment of schizophrenia and the future position of the novel/atypical antipsychotics

Clozapine-associated adverse drug reactions in 38,349 psychiatric inpatients: drug surveillance data from the AMSP project between 1993 and 2016

Clozapine is a second-generation antipsychotic drug that offers superior treatment results in patients with schizophrenia but is also associated with significant risks. This study analyzes data on pharmacotherapy with clozapine and the associated adverse drug reactions (ADRs) in an inpatient setting including 38,349 patients. Data about the use of clozapine and reports of severe ADRs within the period 1993-2016 were obtained from the multicentered observational pharmacovigilance program "Arzneimittelsicherheit in der Psychiatrie" (AMSP). In total, 586 severe clozapine-associated ADRs were documented (1.53% of all patients exposed). Patients aged ≥65 years had a higher risk of ADRs than patients aged <65 years (1.96 vs. 1.48%; p = 0.021). Significantly more ADRs were attributed to clozapine alone (396; 67.6% of all 586 ADRs) than to a combination with other drugs. The most frequent ADRs were grand mal seizures (0.183% of all 38,349 patients exposed), delirium (0.180%), increased liver enzymes (0.120%), and agranulocytosis (0.107%). We detected 24 cases (0.063%) of clozapine-induced extrapyramidal symptoms, of which 8 (0.021%) were attributed to clozapine alone. Five ADRs resulted in death (0.013%): 2 due to agranulocytosis (41 cases total) (mortality = 4.88%) and 3 due to paralytic (sub)ileus (16 cases) (mortality = 18.75%). The median dose of clozapine in all patients treated was 300 mg/day, in patients who developed ADRs 250 mg/day. The main risk factor for an ADR was pre-existing damage of the affected organ system. Overall, the results of this study highlight the importance of alertness-especially of frequently overlooked symptoms-and appropriate monitoring during treatment with clozapine, even at low doses.

Antipsychotic agents. Gradually improving treatment from the traditional oral neuroleptics to the first atypical depot

Relapse is one of the key factors in the long-term outcome of schizophrenia. The consequences of relapse are diverse and often unpredictable, and the time to recovery and degree of recovery worsen with each successive relapse. There is now overwhelming evidence that advances in antipsychotic drug treatment have led to significant reductions in the rate of relapse. This review charts the developments that have taken place in antipsychotic therapy from the introduction of depot formulations, through atypical agents, to the development of the first long-acting atypical antipsychotic. Depot formulations of conventional antipsychotics were developed in the 1960s and led to fewer relapses and episodes of hospitalization, compared with oral equivalents. Meta-analysis has confirmed that patients receiving depot antipsychotics experience significantly greater global improvement than those receiving the respective oral agents. Conventional antipsychotics are, however, associated with a range of potentially serious adverse events. The atypical antipsychotics were introduced in the 1990s and have significant advantages over conventional agents with regard to positive and negative symptoms. There is also evidence that atypical agents can reduce the risk of relapse. Importantly, atypical antipsychotics have an improved safety profile compared with older agents, particularly with regard to extrapyramidal symptoms. One disadvantage of atypical agents has been that they are only available in an oral form. The recent development of a long-acting injectable formulation of risperidone means that a new treatment option is available to physicians.

Psychopharmacological Treatment of Schizophrenia Over Time in 30 908 Inpatients: Data From the AMSP Study

BACKGROUND

Psychotropic drugs are the cornerstone of schizophrenia treatment, often requiring lifelong treatment. Data on pharmacotherapy in inpatient settings are lacking.

METHODS

Prescription data of schizophrenic inpatients within the time period 2000-2015 were obtained from the database of the Drug Safety Program in Psychiatry (AMSP). Data were collected at 2 index dates per year; the prescription patterns and changes over time were analyzed.

RESULTS

Among 30 908 inpatients (mean age 41.6 years, 57.8% males), the drug classes administered most often were antipsychotics (94.8%), tranquilizers (32%), antidepressants (16.5%), antiparkinsonians (16%), anticonvulsants (14.1%), hypnotics (8.1%), and lithium (2.1%). The use of second-generation antipsychotics significantly increased from 62.8% in 2000 to 88.9% in 2015 (P < .001), whereas the prescription of first-generation antipsychotics decreased from 46.6% in 2000 to 24.7% in 2015 (P < .001). The administration of long-acting injectable antipsychotics decreased from 15.2% in 2000 to 11.7% in 2015 (P = .006). Clopazine was the most often used antipsychotic, having been used for 21.3% of all patients. Polypharmacy rates (≥5 drugs) increased from 19% in 2000 to 26.5% in 2015. Psychiatric polypharmacy (≥3 psychotropic drugs) was present in 44.7% of patients.

CONCLUSIONS

Combinations of antipsychotics and augmentation therapies with other drug classes are frequently prescribed for schizophrenic patients. Though treatment resistance and unsatisfactory functional outcomes reflect clinical necessity, further prospective studies are needed on real-world prescription patterns in schizophrenia to evaluate the efficacy and safety of this common practice.

Higher than recommended dosages of antipsychotics in male patients with schizophrenia are associated with increased depression but no major neurocognitive side effects: Results of a cross-sectional pilot naturalistic study

INTRODUCTION

The current small pilot naturalistic cross-sectional study assesses whether higher dosages of antipsychotics are related to a satisfactory outcome concerning symptoms of schizophrenia but also to a worse outcome in terms of adverse events and neurocognitive function.

MATERIAL AND METHODS

41 male stabilized hospitalized schizophrenic patients were assessed by PANSS, Calgary Depression Rating Scale, UKU and Simpson-Angus Scale and a battery of neurocognitive tests. Medication and dosage was prescribed according to clinical judgement of the therapist.

RESULTS

Clinical variables and adverse events did not differ between patients in the recommended vs high dosage groups. Higher dosage correlated with depressive symptoms but there was no correlation with neurocognitive measures except for impaired concentration.

DISCUSSION

Results suggest that it is possible to achieve a good clinical response in refractory patients by exceeding recommended antipsychotic dosages at the price of depression and possible mild isolated concentration deficits but not other neurocognitive or extrapyramidal adverse events. Currently clinicians prefer first-generation antipsychotics when high dosages are prescribed, but considering the more favorable adverse effects profile of newer agents, it is important to study higher dosages of these agents and to test whether they should be preferably given when high dosages are necessary.

Treatment Response in First-episode Schizophrenia

First episode schizophrenia (FES) patients tend to be more responsive to treatment. An adequate response has been associated with a favourable long-term course in FES patients. Yet, despite the generally very favourable response profile around one quarter of the patients shows persisting symptoms of psychosis. To improve the outcome and course of psychosis great effort has emerged in identifying biological and clinical variables associated with non-response in order to identify non-responders as early as possible and adopt specific treatment strategies improving illness outcome. Different antipsychotic treatment regimens have been evaluated in terms of their efficacy in reducing symptoms of FES with psychological interventions gaining increasing importance in the treatment concept of patients suffering from their first illness episode. Therefore, aim of this review is to summarize current evidence on the response patterns, the most important predictors of response/non-response as well as on effective treatment interventions in FES patients.

Evidence-based medicine in psychopharmacotherapy: possibilities, problems and limitations

Psychopharmacotherapy should now be regulated in the sense of evidence-based medicine, as is the case in other areas of clinical treatment in medicine. In general this is a meaningful development, which principally will have a positive impact on routine health care in psychiatry. But several related problems should not be ignored. So far consensus on an internationally accepted evidence graduation could not be reached due to several difficulties related to this. For example, focussing on the results of meta-analyses instead of considering relevant single studies results in a decision-making logic which is in conflict with the rationale applied by drug authorities in the licensing process. Another example is the relevance of placebo-controlled trials: if randomized placebo-controlled phase-III studies are prioritized in the evidence grading, the evidence possibly deviates too far from the conditions of routine clinical care due to the special selection of patients in those studies. However, a grading primarily based on active comparator trials could lead to wrong conclusions about efficacy. This concerns especially the so-called "effectiveness" studies and other forms of phase-IV studies with their less restrictive methodological rigidity. Attempts to regulate psychopharmacotherapy in the sense of evidence-based medicine come closer to their limits the more complex the clinical situation and the respective decision-making logic are. Even in times of evidence-based medicine a large part of complex clinical decision-making in psychopharmacotherapy still relies more on clinical experience and a consensus on clinical experience, traditions and belief systems than on results of efficacy oriented phase-III and effectiveness-oriented phase-IV clinical studies.

Improved body weight and metabolic outcomes in overweight or obese psychiatric patients switched to amisulpride from other atypical antipsychotics

Switching to a different second-generation antipsychotic (SGA) with a lower risk of weight gain is recommended for overweight or obese psychiatric patients undergoing SGA treatment. However, there have been no complete reports regarding the long-term metabolic effects of switching to amisulpride. In this open-label 1-year study, we investigated the effects on body weight and other metabolic profiles when psychiatric patients treated with another SGA were switched to amisulpride treatment. Forty-six schizophrenia or schizoaffective inpatients with a body mass index greater than 27 kg/m were enrolled in the switch group. These patients were cross-titrated to amisulpride treatment and followed up for 1 year prospectively. Another 46 inpatients matched with the baseline body mass index of those in the switch group were enrolled as the control group retrospectively. The results showed that the switch group had greater weight loss than the control group (7.80 +/- 6.67 vs 2.60 +/- 6.23 kg, respectively; repeated-measure analysis of variance, P < 0.0005). During the treatment course, the amisulpride-treated patients showed significantly decreased fasting triglyceride, total cholesterol, glucose, and insulin resistance levels; decreased diastolic blood pressure and pulse rate; and a significant increase in high-density lipoprotein cholesterol levels after switching to amisulpride (all with a P < 0.05). The prevalence of metabolic syndrome in amisulpride-treated patients also decreased significantly from 65.2% to 30.4% (McNemar test, P < 0.0005). These findings suggest that switching to amisulpride could be an effective treatment of overweight or obese psychiatric patients treated previously with other SGAs.

Is evidence sufficient for evidence-based medicine?

Psychopharmacotherapy should now be regulated in the sense of evidence-based medicine (EBM), as is the case in other areas of clinical treatment in medicine. In general this is a meaningful development, which will principally have a positive impact on routine health care in psychiatry. But several related problems should not be ignored. So far consensus on an internationally accepted evidence graduation could not be reached, due to several difficulties related to this. A principle question is also whether it is sufficient to base EBM primarily on the results of phase III trials with their high internal validity. Restrictions to generalise findings of phase III trials suggest the need for additional sources of evidence, amongst others "effectiveness" studies and other kinds of phase IV studies with their less restrictive methodological standards. Attempts to regulate psychopharmacotherapy in the sense of evidence-based medicine come closer to their limits the more complex the clinical situation and the respective decision-making logic are. Even in times of evidence-based medicine we are faced with the situation that a large part of complex clinical decision-making in psychopharmacotherapy still relies more on personal clinical experience and a group consensus about clinical experience, traditions and belief systems than on results of efficacy oriented phase III and effectiveness-oriented phase IV clinical studies.

Novel Antipsychotics in the Long-term Treatment of Schizophrenia

Schizophrenia still has a poorer outcome than other affective disorders. One possible way to improve the long-term outcome of schizophrenic patients is to optimise long-term treatment with the aim of minimising the number of relapses and reducing residual symptoms. Atypical antipsychotics have various advantages over atypical neuroleptics. The first depot formulation of an atypical neuroleptic appears to be a further positive step to improve the possibilities of an optimal long-term treatment for schizophrenia.

Short-term treatment with risperidone or haloperidol in first-episode schizophrenia: 8-week results of a randomized controlled trial within the German Research Network on Schizophrenia

Patients with first-episode schizophrenia appear to respond to lower doses of neuroleptics, and to be more sensitive to developing extrapyramidal side-effects. The authors therefore compared in such patients the efficacy and extrapyramidal tolerability of comparatively low dosages of the atypical neuroleptic risperidone and of the conventional neuroleptic haloperidol. Risperidone was hypothesized to have better extrapyramidal tolerability and efficacy in treating negative symptoms. Patients were randomly assigned under double-blind conditions to receive risperidone (n=143) or haloperidol (n=146) for 8 wk. The primary efficacy criterion was the estimated difference in the mean change in the Positive and Negative Symptom Scale (PANSS) negative score between treatment groups; secondary efficacy criteria were changes on the PANSS total score and other PANSS subscores, and several other measures of psychopathology and general functioning. The primary tolerability criterion was the difference in baseline-adjusted occurrence rates of extrapyramidal side-effects measured with the Simpson-Angus Scale (SAS) compared between treatment groups. The main hypothesis was that risperidone would be superior in terms of improving negative symptoms and lowering the risk of extrapyramidal symptoms. Secondary tolerability criteria were the other extrapyramidal symptoms, measured with the Hillside Akathisia Scale (HAS) and the Abnormal Involuntary Movement Scale (AIMS). The average mean daily doses were 3.8 mg (s.d.=1.5) for risperidone and 3.7 mg (s.d.=1.5) for haloperidol. There were similar, significant improvements in both treatment groups in the primary and secondary efficacy criteria. At week 8 nearly all scores of extrapyramidal side-effects indicated a significantly higher prevalence of extrapyramidal side-effects with haloperidol than with risperidone [SAS: risperidone 36.5% of patients; haloperidol 51.5% of patients; likelihood ratio test, chi2(1)=7.8, p=0.005]. There were significantly fewer drop-outs [risperidone n=55, drop-out rate=38.5%; haloperidol n=79, drop-out rate=54.1%, chi2(1)=7.1, p=0.009] and a longer non-discontinuation time [risperidone: average of 50.8 d to drop-out; haloperidol: average of 44.0 d to drop-out; log rank test, chi2(1)=6.4, p=0.011] in the risperidone group. Risperidone and haloperidol appear to be equally effective in treating negative and other symptoms of first-episode schizophrenia. Risperidone has better extrapyramidal tolerability and treatment retention rate than the equivalent dose of haloperidol in these patients.

Importance of open access to atypical antipsychotics for the treatment of schizophrenia and bipolar disorder: a European perspective

OBJECTIVE

To assess European psychiatrists' prescribing behaviour and their perceived need for access to a wide range of atypical antipsychotics for patients with schizophrenia and bipolar disorder.

METHODS

A blinded, internet survey of psychiatrists from the UK, Germany, Italy and the Netherlands occurred in 2007. Key inclusion criteria for psychiatrists: practising full time; practising for 5-35 years; prescribed atypical antipsychotics in prior 6 months to > or =20 patients with schizophrenia or bipolar disorder. Eligible psychiatrists selected records for four patients with schizophrenia or bipolar disorder for whom they prescribed > or =1 atypical antipsychotic since January 2004.

RESULTS

Survey response rates were: UK, 14.8% (n = 107); Germany, 9.6% (n = 104); Italy, 8.9% (n = 101) and the Netherlands, 3.7% (n = 51); 363 psychiatrists reported on 1442 patients. Psychiatrists perceived a greater difference among atypical antipsychotics as a class (mean, 5.1 on a 7-point scale [7 = 'highly differentiated']) but not selective serotonin reuptake inhibitors (mean, 3.6). On average, psychiatrists used 6.8 different atypical antipsychotics across their patients with schizophrenia and 4.4 across their patients with bipolar disorder, with 2.5 and 2.4 changes required following first-line treatment to stabilise therapy, respectively. The most common reason for switching medication was lack of efficacy. Psychiatrists reported that expected consequences for patients should access to atypical antipsychotics be restricted would include illness deterioration, non-adherence and hospitalisation.

CONCLUSIONS

Although this study is limited by potential selection biases, these data suggest that European psychiatrists tailor antipsychotic medications for patients with schizophrenia or bipolar disorder according to patients' needs and specific drug attributes.

Medications Development for the Treatment of Nicotine Dependence in Individuals with Schizophrenia

The development of medications for the treatment of nicotine dependence in patients with schizophrenia is a public health priority due to its high prevalence rates, devastating medical consequences, and difficulty to treat. It has been hypothesized that the high prevalence of nicotine dependence among patients with schizophrenia may be due to a shared neurobiological vulnerability. This shared vulnerability has been evidenced in reports showing that nicotine improves neuropsychological deficits associated with schizophrenia such as in the P50 evoked auditory potentials, spatial working memory, and attention. The common pathophysiologic pathways of smoking and schizophrenia may serve as the basis for the pharmacological evaluation of medications for the treatment of these concurrent disorders. Currently, little research of medications for the treatment of this comorbidity has been conducted. Studies have evaluated the efficacy of smoking cessation medications in patients with schizophrenia. These include the nicotine replacement therapy (patch, nasal spray) and sustained release bupropion. Others have evaluated the anti-smoking effect of medications (e.g., clozapine, haloperidol) used for the treatment of schizophrenia. In both cases, the results have not been conclusive. Newer smoking cessation approaches such as varenicline, selegiline, rimonabant, and nicotine vaccine, among others, have yet to be tested in this population. The purpose of this article is to review the results of the studies conducted to date and propose some potential pharmacotherapies based on the current knowledge of the pathophysiology of both disorders.

Probleme der „evidence-based medicine“ in der Psychopharmakotherapie: Problematik der Evidenzgraduierung und der Evidenzbasierung komplexer klinischer Entscheidungsprozesse

Psychopharmacotherapy should now be regulated in the sense of evidence based medicine, as is the case in other areas of therapeutic medicine. In general, this is a meaningful development which will have a positive impact on routine health care. However, related problems should not be ignored. One important problem is the different definition of degrees of evidence. If placebo-controlled studies are prioritized, evidence deviates too much from the conditions of routine clinical care. However, the restriction to active comparative trials could lead to false conclusions about efficacy. In addition, if the focus is placed on the results of meta-analyses instead of considering relevant single studies, the result is a decision making logic contrary to that of the licensing process.Due to inherent methodological problems of the meta-analytical approach, the narrative, systematic review should retain its traditional importance and be used to provide a complementary view. Attempts to regulate psychopharmacotherapy in the sense of evidence based medicine come closer to their limits the more complex the clinical situation and the respective decision making logic are. Even in times of evidence based medicine, a large part of complex clinical decision making in psychopharmacotherapy still relies more on a consensus about clinical experience and traditions than on relevant empirical databases.

Do differences in atypical antipsychotics matter in routine practice? Medication switch from olanzapine and risperidone to amisulpride

Atypical antipsychotics are often addressed as one class of drugs, although there are marked differences in their pharmacological profiles. It is unknown how this is seen by practitioners and to what extent they differentiate between the various atypical compounds. In a drug utilization study, 472 schizophrenic outpatients who were switched for individual reasons from either olanzapine or risperidone to amisulpride were monitored. Data on patients, illness and treatment as well as on reasons to switch were collected. The reasons to switch from olanzapine to amisulpride were preferably 'weight gain' (72.6% of the physicians), or the 'expectancy of less weight gain with amisulpride' (84.1%) and 'patient request' (60.2%). Specific reasons to switch from risperidone were 'extrapyramidal symptoms' (58.5%), or the 'expectancy of few extrapyramidal symptoms with amisulpride' (82.5%). In conclusion, this study confirms that physicians do not consider 'atypical antipsychotics' as one homogeneous class of drugs but make differences that reflect the specific pharmacological profiles of the respective drugs.

Long-Acting Injectable Risperidone for the Treatment of Schizophrenia

Schizophrenia remains a severe disorder that is associated with a poor outcome in a large subgroup of patients. Major efforts should be made to improve treatment for all patients who have this debilitating disease. Second-generation antipsychotics were a major step forward in this respect; however, important unmet needs remain, such as a better solution for frequent noncompliance problems. Depot formulations are known to have advantages in this respect. However, for a long time, only depot formulations of conventional antipsychotics were available, with their high risk of extrapyramidal adverse effects. Therefore, there has been only very restricted use of depot antipsychotics, which mainly focused on patients with chronic disease who were difficult to treat and had a high risk of noncompliance. The situation may change with the advent of a depot formulation of an atypical antipsychotic. The first depot formulation of an atypical antipsychotic to be introduced to the market is long-acting injectable risperidone. On the basis of the pharmacokinetic properties of the depot formulation, a 2-week interval between administrations is recommended. The antipsychotic efficacy of long-acting risperidone was demonstrated in two 12-week, double-blind, randomised, phase III studies, one versus placebo and the other versus oral risperidone. These two studies, together with one open-label, long-term study over 12 months, belong to the core group of trials that were relevant for the licensing of long-acting risperidone. A relapse-prevention, control group study comparing the long-acting formulation versus oral risperidone was not performed because of the known principal methodological problems of such a comparison. Instead, as much clinical data as possible was collected from observational studies that investigated questions relevant for clinical practice, such as efficacy, safety and tolerability in different subgroups, and transition from pre-treatment with different kinds of antipsychotics to long-acting risperidone. On the basis of these data, it can be stated that the efficacy of the long-term formulation of risperidone is proven, and that the safety and tolerability are more or less comparable to those of oral risperidone. The local tolerability at the injection site is good. Because it is well known that noncompliance is a frequent feature of the treatment of schizophrenia, and considering the advantages of atypical antipsychotics, consideration of whether long-acting atypical antipsychotics should have a broader indication than is the case with the depot formulations of the classical antipsychotics is warranted.

Risperidone: a review

When the risk of agranulocytosis associated with clozapine, the prototype of the second-generation neuroleptics, became apparent, its prescription was restricted to patients refractory to classical neuroleptics such as chlorpromazine and haloperidol. This stimulated the development of several novel second-generation antipsychotics with a clinical profile similar to that of clozapine. These novel antipsychotics, which include risperidone, olanzapine and others, are characterised by different pharmacological structures, and also to a certain degree by different pharmacological mechanisms. Following the increased research on the novel second-generation antipsychotics, it became apparent that they not only have the advantage of better extrapyramidal tolerability than the classical neuroleptics, but also have a broader efficacy spectrum (i.e., advantages in the treatment of negative and depressive symptoms and cognitive disturbances in the context of schizophrenia). Risperidone was specifically designed by Paul Janssen as a combined 5-HT2A and D2 receptor antagonist, thus following the pharmacological mechanism thought to be responsible for the antipsychotic effects of clozapine. After its advent in the 1990s as the first novel second-generation antipsychotic, risperidone achieved worldwide acceptance. The following review gives an overview of the huge clinical database available for risperidone in the field of schizophrenia.

Occurrence and treatment of depressive comorbidity/cosyndromality in schizophrenic psychoses: conceptual and treatment issues

Depressive symptoms are a common feature of schizophrenic disorders, a fact that has become increasingly apparent over the last two decades. Apparently the introduction of standardized rating scales in cross-sectional and longitudinal investigations played an important role in the recognition of the relevance of depressive symptoms. They can be interpreted as being cosyndromal or comorbid, depending on the conceptual perspective applied. This is not simply a difference in terminology but is of great aetiopathogenetic relevance. Of particular clinical relevance is the observation that schizophrenic patients with concomitant depressive symptoms have a greater risk of suicidality or an unfavourable disease course. For this reason it is important that sufficient attention is paid to the diagnosis and treatment of depressive symptoms occurring during schizophrenic psychoses. Besides treatment with antidepressants, modern neuroleptics are of great importance in this context as they are more efficacious than classical neuroleptics in treating depressive symptoms.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for biological treatment of schizophrenia, Part 1: acute treatment of schizophrenia

These guide lines for the biological treatment of schizophrenia were developed by an international Task Force of the World Federation of Societies of Biological Psychiatry (WFSBO). The goal during the development of these guidelines was to review systematically all available evidence pertaining to the treatment of schizophrenia, and to reach a consensus on a series of practice recommendations that are clinically and scientifically meaningful based on the available evidence. These guidelines are intended for use by all physicians seeing and treating people with schizophrenia. The data used for developing these guidelines have been extracted primarily from various national treatment guidelines and panels for schizophrenia, as well as from meta-analyses, reviews and randomised clinical trials on the efficacy of pharmacological and other biological treatment interventions identified by a search of the MEDLINE database and Cochrane Library. The identified literature was evaluated with respect to the strength of evidence for its efficacy and then categorised into four levels of evidence (A-D). This first part of the guidelines covers disease definition, classification, epidemiology and course of schizophrenia, as well as the management of the acute phase treatment. These guidelines are primarily concerned with the biological treatment (including antipsychotic medication, other pharmacological treatment options, electroconvulsive therapy, adjunctive and novel therapeutic strategies) of adults suffering from schizophrenia.

Modern antipsychotic drugs: a critical overview

Conventional antipsychotic drugs, used for a half century to treat a range of major psychiatric disorders, are being replaced in clinical practice by modern "atypical" antipsychotics, including aripiprazole, clozapine, olanzapine, quetiapine, risperidone and ziprasidone among others. As a class, the newer drugs have been promoted as being broadly clinically superior, but the evidence for this is problematic. In this brief critical overview, we consider the pharmacology, therapeutic effectiveness, tolerability, adverse effects and costs of individual modern agents versus older antipsychotic drugs. Because of typically minor differences between agents in clinical effectiveness and tolerability, and because of growing concerns about potential adverse long-term health consequences of some modern agents, it is reasonable to consider both older and newer drugs for clinical use, and it is important to inform patients of relative benefits, risks and costs of specific choices.

Antipsychotic and antidepressive effects of second generation antipsychotics: two different pharmacological mechanisms?

Second generation antipsychotics display antidepressive effects in schizophrenic patients that are more pronounced than those of traditional neuroleptics and that go beyond antidepressive effects secondary to the reduction of positive symptoms. The antidepressive potential of second generation antipsychotics is presumably related to their pharmacological mechanisms, which differ from those of traditional neuroleptics. Among others, 5-HT(2A) antagonism is of special relevance for most of the new antipsychotics in this respect. But also special interactions with the dopaminergic system, as is the case with amisulpride and aripiprazole, or noradrenalin- and/or serotonin-reuptake-inhibition, as with ziprasidone and zotepine, should be considered. It can be summarised that the antipsychotic and antidepressive effects of second generation antipsychotics are mostly based on different pharmacological mechanisms. This might be especially true for direct antidepressive effects, i. e. antidepressive effects that are not mediated by the reduction of positive symptoms.

Antidepressive effects of traditional and second generation antipsychotics: a review of the clinical data

For a long time,in the context of depressive symptoms in schizophrenia traditional neuroleptics were mostly discussed with respect to possible depressiogenic side effects, although some studies argued that they may also have certain antidepressive effects. However, this was not proven at that time in placebo-controlled studies. Placebo-controlled studies performed in recent years have shown that second generation antipsychotics have antidepressive effects which are significantly stronger than those of the traditional neuroleptics. In addition, it was demonstrated that this antidepressive effect can only partially be explained as being secondary to the improvement of positive and negative symptoms, and is apparently predominantly due to a direct (primary) effect on depressive symptoms. It is of special relevance in this context that the antidepressive effect of second generation antipsychotics was recently demonstrated in depression. The positive results from some studies in bipolar depression are especially impressive and underline the antidepressive potencies of novel antipsychotics beyond the spectrum of schizophrenia.

Extrastriatal and striatal D(2) dopamine receptor blockade with haloperidol or new antipsychotic drugs in patients with schizophrenia

BACKGROUND

Both traditional and atypical antipsychotics have been hypothesised to be effective in schizophrenia through limbic and cortical D(2) dopamine receptor blockade.

AIMS

To investigate this hypothesis with the D(2)/D(3)-selective positron emission tomography (PET) probe [(76)Br]-FLB457.

METHOD

PET scans were performed on 6 controls and 18 patients with schizophrenia treated with haloperidol or with risperidone, clozapine, amisulpride or olanzapine.

RESULTS

The D(2) dopamine receptor blockade was high in the temporal cortex with both haloperidol and atypical antipsychotics. The atypicals, however, induced a significantly lower D(2) binding index than haloperidol in the thalamus and in the striatum.

CONCLUSIONS

Results suggest that cortical D(2) dopamine receptors are a common target of traditional and atypical antipsychotics for therapeutic action. Higher in vivo binding to the D(2) receptors in the cortex than in the basal ganglia is suggested as an indicator of favourable profile for a putative antipsychotic compound.