More on clozapine

Exploring clozapine use in severe psychiatric symptoms associated with autism spectrum disorder: A scoping review

BACKGROUND

Patients with autism spectrum disorder (ASD) may experience severe psychiatric symptoms, often unresponsive to conventional pharmacological therapies, highlighting the need for more effective alternatives.

AIMS

This study aims to map and synthesize evidence on the use of clozapine as a therapeutic option for managing severe psychiatric symptomatology co-occurring with ASD.

METHODS

We conducted a scoping review on multiple sources following the JBI guidelines. The search strategy was inclusive, targeting both peer-reviewed publications and gray literature presenting empirical data on the use of clozapine therapy for patients with ASD accompanied by comorbid psychiatric symptoms. Two independent evaluators performed the selection of studies, data extraction, and critical appraisal.

RESULTS

The review included 46 studies, encompassing 122 ASD individuals who received clozapine therapy. The sources of evidence comprise 31 case reports, 8 case series, 6 retrospective observational studies, and 1 quasi-experimental prospective study. The tables present the findings along with a narrative summary. Clozapine treatment demonstrated benefits in four groups of severe and treatment-resistant psychiatric symptoms in ASD patients: disruptive behaviors, psychotic symptoms, catatonia, and mood symptoms. Although side effects were common, tolerability was generally satisfactory. However, severe adverse events, such as seizures, moderate neutropenia, and myocarditis, underscore the need for intensive clinical monitoring.

CONCLUSIONS

While clozapine shows promise as a pharmacological intervention for severe psychopathologies in ASD, more rigorous clinical studies are required to elucidate its efficacy and safety in this population. The limited robustness of the evidence calls for caution, signaling an early research stage into this topic.

Second-generation antipsychotic medications in children and adolescents

OBJECTIVE

We reviewed available pediatric literature on second-generation antipsychotic medications to assess current evidence of efficacy and safety.

METHOD

An English language MEDLINE search (1974-2003) was conducted using key words-atypical antipsychotics, children and adolescents, toxicity, clozapine, risperidone, olanzapine, quetiapine, ziprasidone, and aripiprazole. Additional efficacy and safety data were obtained from drug manufacturers.

RESULTS

We identified 176 reports, including 15 double-blind, controlled trials, 58 openlabel studies, 18 retrospective chart reviews, and 85 case series/reports. The majority of these studies (43%) were of risperidone. Evidence suggests that second-generation antipsychotics are efficacious in the treatment of psychosis, bipolar disorders, pervasive developmental disorders, and Tourette's Disorder, and are potentially useful in mental retardation, conduct disorder, and severe attention deficit hyperactivity disorder (ADHD). The most frequently reported side effects included cardiovascular effects, weight gain, sedation, sialorrhea, extrapyramidal signs, and hyperprolactinemia, although the relative frequencies of these untoward effects vary among medications.

CONCLUSION

Although the evidence base for pediatric use of second-generation antipsychotics is expanding, the majority of available studies are anecdotal, or short-term, openlabel trials. Reports suggest that these compounds are effective for a variety of psychiatric disorders in children and adolescents, but additional double-blind, controlled studies are required to establish definitive efficacy. Although these medications appear to be well tolerated in short-term studies, long-term follow-up investigations and ongoing clinical monitoring are necessary to confirm their safety in this age group.

Benefit-Risk Assessment of Atypical Antipsychotics in the Treatment of Schizophrenia and Comorbid Disorders in Children and Adolescents

Evidence on the efficacy and safety of atypical antipsychotics in children and adolescents with schizophrenia is limited. The purpose of this review is to assess the published data on the use of atypical antipsychotics in children and adolescents with schizophrenia alone and with comorbid disorders, and to establish benefit-risk guidelines for clinicians.Risperidone, olanzapine and clozapine were found to be effective in the treatment of aggression and mania. Risperidone, and possibly also olanzapine, may be the drugs of choice in children with comorbid tic disorders. Ziprasidone has some monoamine reuptake inhibition properties and may be administered as an augmenting agent in children and adolescents with schizophrenia and comorbid anxiety and mood disorders. Compared with the typical antipsychotics, the atypical drugs seem to be more effective, better tolerated and lead to better patient adherence. Importantly, the atypical antipsychotics have a lower propensity to induce extrapyramidal symptoms and a potential (shown so far only in adults) to improve cognitive function and inhibit suicidal behaviour (especially clozapine). Yet, the adverse effects associated with these agents, especially weight gain, which may also have long-term effects, can lead to non-compliance in the young population. In children and adolescents receiving clozapine, olanzapine and quetiapine (but not ziprasidone, which does not have a pro-appetite effect), particularly those with obesity or a family history of diabetes mellitus, fasting blood glucose and lipid levels must be monitored frequently. Weight gain might be better controlled when the children and their parents are properly informed about this adverse effect and diet is regulated. Another major disadvantage of the atypical antipsychotics, especially risperidone, is their association with hyperprolactinaemia, which can lead to hypogonadism-induced osteoporosis, galactorrhoea, gynaecomastia, irregular menstruation and sexual dysfunction, all seen also with typical antipsychotics. Other atypical antipsychotics, namely olanzapine and ziprasidone, have been reported to be prolactin sparing in adults, but may not be completely devoid of hyperprolactinaemic effects in children and adolescents. Thus, prolactin levels should be assessed routinely in young patients treated with atypical antipsychotics. Further, children and adolescents with hyperprolactinaemia-related effects should be switched to a prolactin-sparing agent, such as quetiapine. All atypical antipsychotics may induce sedation and they are not devoid of extrapyramidal symptoms (especially risperidone). The use of typical antipsychotics has been limited to patients who are resistant to atypical antipsychotics, intolerant to their adverse effects, or require injections or depot preparations. Further double-blind, placebo-controlled trials and long-term safety assessments are needed before definitive conclusions can be reached about the place of atypical antipsychotics in the therapeutic armamentarium of childhood-onset schizophrenia.

Paediatric uses of atypical antipsychotics

Antipsychotics are commonly prescribed to children and adolescents. With the relatively recent availability of the atypical antipsychotics, physicians have begun prescribing these agents to young people in the hope of finding safe, effective alternatives to the typical antipsychotics. This report reviews what is currently known about the use of the atypical antipsychotics in young people. Most of the currently available data are based on case reports and case series. The results of only a handful of prospective trials pertaining to the use of the atypical antipsychotics in youths have been reported. Based on the available information, it appears that clozapine has a role in juvenile treatment resistant schizophrenia. When considered as a group, the 'first-line' atypical antipsychotics risperidone, olanzapine and quetiapine appear to have promise as treatments for several neuropsychiatric disorders in young people. These conditions include psychotic, mood, disruptive, movement and pervasive developmental disorders. Unfortunately, as has historically been the case, the demand to address the clinical needs of young patients with neuropsychiatric disorders has outpaced empirically based information. This is particularly important because significant side effects can occur when children or adolescents are treated with atypical antipsychotics. Since there is a paucity of short-term and almost no long-term safety data pertaining to these agents in young people, careful consideration must be made prior to initiating atypical antipsychotic treatment for a child or teenager. Based upon what is known about these agents, a rational approach to the use of these drugs in juveniles is offered.

Management of schizophrenia in children and adolescents. The role of clozapine

Clozapine is a dibenzodiazepine derivative with established antipsychotic efficacy in adult patients with schizophrenic psychoses. There are more than 15 studies that have also demonstrated the antipsychotic efficacy of clozapine in childhood and adolescent schizophrenia. The main advantages of clozapine treatment in this age group in comparison with typical antipsychotics are: (i) high antipsychotic efficacy during an acute schizophrenic episode; (ii) better improvement in chronic cases with a high load of negative symptoms; and (iii) markedly fewer extrapyramidal adverse effects and, therefore, fairly good tolerability. However, because of its possible adverse effects on the haemopoetic system (granulocytopenia, agranulocytosis), clozapine should not be used as first-line antipsychotic medication. Other adverse effects are related to the cardiovascular system (hypotonia, tachycardia or arrhythmia), the central nervous system (epileptic seizures, fever) and liver function (transient increases in levels of hepatic transaminases). Two other frequent adverse effects are hypersalivation and body-weight gain, which may present a particular problem in adolescents and young adults. Careful monitoring of haematological parameters and other adverse effects are preconditions for a successful treatment programme.

Clozapine for early developmental delays with childhood-onset schizophrenia: protocol and 15-month outcome

This paper reports on the pharmacotherapy and long-term follow-up of a child treated with clozapine. It is one of the earliest American experiences with this agent in children to date. Clozapine was relatively effective and safe in this patient. Additional features of the case are the early social and developmental delays preceding schizophrenia, the response of symptoms of childhood-onset schizophrenia to clozapine, and the reduction in tardive dyskinesia symptoms while taking clozapine. Compared to recommendations for dosing adults, a slower rate of increasing clozapine doses was important for this child. For future reference, the protocol and consent form used for this course of treatment are included.