Atypical neuroleptic malignant syndrome with quetiapine: a case report and review of the literature

Acute Quetiapine Intoxication: Relationship Between Ingested Dose, Serum Concentration and Clinical Presentation-Structured Literature Review and Analysis

Over the past decade, quetiapine has become one of the most commonly used psychotropic drugs in acute intoxication events worldwide. A structured literature review and analysis were conducted to assess the relationship between the kinetic and dynamic profiles in acute quetiapine intoxication. The correlation between dose and peak serum concentration (cmax) was determined using Pearson's correlation coefficient. Binary logistic regression was used to evaluate dose and cmax as predictors of the most common clinical events, signs and symptoms. One hundred and thirty-four cases of acute quetiapine ingestion were included in the analysis, with a median ingested dose of 10 g and a median cmax of 4 mg/L. The typical half-life was estimated to be 16.5 h, significantly longer than at therapeutic doses. For the immediate-release formulation, a biphasic disposition could not be excluded. Dose and cmax demonstrated a weak but significant correlation (r = 0.256; N = 63; p = 0.043). Central nervous system depression and tachycardia were the most common clinical signs. Higher doses and concentrations increased the risk of severe intoxication and were good predictors of intubation, tachycardia, hypotension, QTc prolongation and seizures, but not QRS prolongation, arrhythmia, heart block, hypokalaemia or acidosis. The thresholds for dose and cmax that increased the risk for individual signs and symptoms varied widely. However, doses > 3 g or cmax > 2 mg/L can be considered as alert levels that represent a high risk for severe clinical course of acute quetiapine intoxication.

What clinical analysis of antipsychotic-induced catatonia and neuroleptic malignant syndrome tells us about the links between these two syndromes: A systematic review

OBJECTIVES

Antipsychotic-induced catatonia (AIC) and neuroleptic malignant syndrome (NMS) are life-threatening adverse reactions to antipsychotic medication. We conducted a systematic review of literature following the PRISMA statement guidelines to obtain a description of these syndromes (population, context of occurrence, antipsychotic agents implicated) and draw conclusions about their links.

METHODS

We searched Medline and Web of science databases from January 1951 to May 2019 (further restricted from 2000 to 2019) using search terms including "catatonia", "neuroleptic malignant syndrome" and "antipsychotic agents" for case reports, case series and analytic studies. After screening 4082 records, 410 full-text articles (describing 555 events) were assessed for eligibility. We included events of AIC and/or NMS according to Diagnostic and Statistical Manual (DSM) criteria and extracted data about patients' characteristics, context of occurrence, antipsychotic agent(s) involved and treatment outcomes.

RESULTS

We included 165 events (16 AIC, 129 NMS and 20 AIC + NMS) from 144 case reports and case series. The most reported diagnosis was schizophrenia. Comorbid pre-existing conditions such as central nervous system diseases and acute medical events were common. Most of the events (63.3 %) occurred during antipsychotic monotherapy. Second-generation antipsychotics (SGAs, 63.8 %) were overall more implicated than first-generation antipsychotics (FGAs, 36.2 %).

DISCUSSION

Our findings highlight that any antipsychotic medication, even SGA monotherapy prescribed at recommended dose, is at risk for these side effects. FGAs and polypharmacy seem to represent risk factors for malignant catatonia in AIC. The clinical overlap observed between AIC and NMS events in our review suggests a clinical continuum between catatonia and NMS.

Case reports of neuroleptic malignant syndrome in context of quetiapine use

A retrospective analysis was followed on 20 case reports covering the possible correlation between the atypical antipsychotic, quetiapine, and neuroleptic malignant syndrome (NMS), determined by the study of 7 different NMS criteria guidelines. A great majority (19) of the case studies did not meet the requirements of all 7 guidelines, frequently due to unreported information. Nor was quetiapine proven to be the sole cause of the possible NMS in the two age groups investigated. Only one case was found to have no other medication or medical conditions confounding the relationship of quetiapine and NMS symptoms, and that case was in the context of a significant quetiapine overdose. The other 19 cases demonstrated the difficulty of identifying the cause of NMS when polypharmacy and other medical conditions are involved. The authors note the need for caution in deciding both the presence of NMS and the causal factors of the symptoms.

Neuroleptic malignant syndrome: a review for neurohospitalists

Neuroleptic malignant syndrome (NMS) is a life-threatening idiosyncratic reaction to antipsychotic drugs characterized by fever, altered mental status, muscle rigidity, and autonomic dysfunction. It has been associated with virtually all neuroleptics, including newer atypical antipsychotics, as well as a variety of other medications that affect central dopaminergic neurotransmission. Although uncommon, NMS remains a critical consideration in the differential diagnosis of patients presenting with fever and mental status changes because it requires prompt recognition to prevent significant morbidity and death. Treatment includes immediately stopping the offending agent and implementing supportive measures, as well as pharmacological interventions in more severe cases. Maintaining vigilant awareness of the clinical features of NMS to diagnose and treat the disorder early, however, remains the most important strategy by which physicians can keep mortality rates low and improve patient outcomes.

Is quetiapine suitable for treatment of acute schizophrenia with catatonic stupor? A case series of 39 patients

PURPOSE

We aimed to determine which antipsychotic is most effective for the treatment of acute schizophrenia with catatonic stupor.

PATIENTS AND METHODS

Data were obtained from the medical records of 450 patients with the diagnosis of schizophrenia, who had received acute psychiatric inpatient treatment between January 2008 and December 2010 at our hospital. Among them, 39 patients (8.7%) met the definition of catatonic stupor during hospitalization. The diagnoses of schizophrenia in all 39 patients were reconfirmed during the maintenance phase. We retrospectively reviewed the medical records of these 39 patients to investigate which antipsychotics were chosen for treatment during the period from admission to recovery from catatonia, at the time of discharge, and 12 and 30 months after discharge.

RESULTS

As compared to other antipsychotics, it was found out that use of quetiapine had better outcomes and hence was used more often. A total of 61.5% of patients were on quetiapine at the time of recovery from catatonia and 51.3% of patients were on quetiapine at the time of discharge as compared to only 17.9% of patients on quetiapine on admission. However, at 12 and 30 months after discharge, the rates had decreased to 38.4% and 25.6%. Similarly, of 29 patients who were not administered electroconvulsive therapy, quetiapine was used at significantly higher rates at the time of recovery from catatonia (48.3%) than at the time of admission (17.2%). All 39 patients had received an antipsychotic as the first-line treatment and some antipsychotics might have contributed to the development of catatonia.

CONCLUSION

This study suggests that quetiapine is a promising agent for the treatment of schizophrenia with catatonic stupor during the acute phase.

World Federation of Societies of Biological Psychiatry (WFSBP) Guidelines for Biological Treatment of Schizophrenia, part 1: update 2012 on the acute treatment of schizophrenia and the management of treatment resistance

These updated guidelines are based on a first edition of the World Federation of Societies of Biological Psychiatry Guidelines for Biological Treatment of Schizophrenia published in 2005. For this 2012 revision, all available publications pertaining to the biological treatment of schizophrenia were reviewed systematically to allow for an evidence-based update. These guidelines provide evidence-based practice recommendations that are clinically and scientifically meaningful and these guidelines are intended to be used by all physicians diagnosing and treating people suffering from schizophrenia. Based on the first version of these guidelines, a systematic review of the MEDLINE/PUBMED database and the Cochrane Library, in addition to data extraction from national treatment guidelines, has been performed for this update. The identified literature was evaluated with respect to the strength of evidence for its efficacy and then categorised into six levels of evidence (A-F; Bandelow et al. 2008b, World J Biol Psychiatry 9:242). This first part of the updated guidelines covers the general descriptions of antipsychotics and their side effects, the biological treatment of acute schizophrenia and the management of treatment-resistant schizophrenia.

Neuroleptic malignant syndrome

Neuroleptic malignant syndrome (NMS) is a potentially fatal adverse event associated with the use of antipsychotics (AP). The objective of this study was to investigate the profile of cases of NMS and to compare our findings with those published in similar settings. A series of 18 consecutive patients with an established diagnosis of NMS was analyzed, gathering data on demography, symptoms and signs. Two thirds of all cases involved woman with a past medical history of psychiatric disorder receiving relatively high doses of AP. The signs and symptoms of NMS episodes were similar to those reported in other series and only one case had a fatal outcome, the remaining presenting complete recovery. As expected, more than two thirds of our cases were using classic AP (68%), however the clinical profile of these in comparison with those taking newer agent was similar. Newer AP also carry the potential for NMS.