Off-label use of quetiapine in New Zealand--a cause for concern? (original) (raw)
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Patterns of quetiapine use in psychiatric inpatients: an examination of off-label use
Annals of clinical psychiatry : official journal of the American Academy of Clinical Psychiatrists
, there is little data concerning patterns of such use. To investigate such usage of quetiapine, we evaluated prescribing practices of this drug at our acute-care psychiatric hospital. Methods. Inpatient orders for quetiapine were obtained from October 2004 to March 2006 and divided into standing or prn (as needed) dose regimens. For patients receiving standing dose regimens, diagnosis, total daily dose, and dosing adequacy were ascertained. For patients receiving prn dosing, diagnosis, behavioral indication, dose, and frequency were determined. Results. The most common diagnoses in patients receiving standing dose quetiapine were depressive disorders, followed by substance-related, bipolar, and psychotic disorders. Mean dose was 169 ± 154 mg/day (median=200 mg/day), with 29.8% of patients receiving ≥ 300 mg/day. Only 28.5% of patients had one of the diagnoses for which quetiapine is approved; in these patients, 46.4% received ≥ 300 mg/day. Patients receiving prn dosing had a similar distribution of diagnoses. The most common prn dose was 50 mg, given for agitation or insomnia. Conclusion. We found extensive off-label use of quetiapine. Further research is needed on the safety and efficacy of quetiapine in non-approved doses and diagnoses.
The lesser of two evils: a qualitative study of quetiapine prescribing by family physicians
CMAJ Open
Q uetiapine is the most widely prescribed antipsychotic in North America. 1,2 In 2008, antipsychotic drugs became the top-selling drug class in the United States, with estimated sales of US$14.6 billion. 1,3 Global antipsychotic sales in 2010 were US$25.4 billion; of these, Seroquel (quetiapine) was the fifth highest selling pharmaceutical worldwide, costing an estimated US$6.8 billion. 4 In Canada, prescriptions for quetiapine rose by 300% between 2005 and 2012. Using the IMS Brogan Canadian CompuScript databases to identify prescribing data, researchers found that 50% of filled antipsychotic prescriptions in Canada were for quetiapine, and most came from family physicians. 2 Although quetiapine is licensed for the treatment of schizophrenia and bipolar disorder and as an adjunctive to antidepressants in moderate to severe depression, much prescribing of quetiapine is offlabel. 2,5 Off-label prescribing of antipsychotics has been studied extensively, including a meta-analysis of 170 studies. 6 Leslie and colleagues 7 examined prescribing data from the US Department of Veteran Affairs and found that 60.2% of the 279 778 patients who received a prescription for an antipsychotic in 2007 had no indication for its licensed use; of these, 43% were prescribed quetiapine. More recently, researchers in the United Kingdom examined prescribing data using The Health Improvement Network, a primary care database of almost 10 million patients. 5 They found that only 36% (n = 4824) of those prescribed quetiapine had a serious mental illness recorded. Insomnia, anxiety and behavioural disturbance in elderly people and children are common reasons for off-label use. 3,6,8 Evidence of benefit for these indications is disputed. 6,9,10 Adverse metabolic, neurologic and cardiovascular effects 9,11 pose a significant risk of harm. 11,12 Maglione and colleagues 6 calculated a number needed to harm of 8 (odds ratio 5.16, 95% confidence interval 2.93-9.51) for neurologic adverse effects in patients with dementia and of 16 (odds ratio 2.72, 95% confidence interval 2.07-3.56) for weight gain and increased appetite in other conditions.
Quetiapine: An Objective Evaluation of Pharmacology,Clinical Uses and Intoxication
2020
Quetiapine is an antipsychotic drug that belongs to the group of nonconventional agents. Mainly used to treat schizophrenia, bipolar depressive disorder, and exacerbations of manic and depressive episodes of this condition. It is also used to prevent these episodes of exacerbation, beside its many off-label uses. Atypical antipsychotics treat negative symptoms of psychosis without causing extra sedation, and help schizophrenics to integrate into society and, in addition, to remove unwanted extrapyramidal symptoms that conventional agents are known to exert. Unfortunately, these agents, including quetiapine, have other drawbacks the most serious of which are those associated with the disease spectrum of metabolic syndrome and, furthermore, the many interactions quetiapine may be involved in with other drugs in cases of polypharmacy. This review gives an update on quetiapine and provides a guideline to psychiatric caregivers, and importantly, undergraduates of medicine and pharmacy students on clinical uses (both dedicated and off-label), pharmacology, pharmacopeia, and intoxication that might occur following its use, and how to treat such a condition.
Quetiapine Abuse Fourteen Years Later: Where Are We Now? A Systematic Review
Substance Use & Misuse, 2019
Background: Quetiapine, an atypical antipsychotic endowed with weak dopamine antagonist, potent 5-HT 2A-blocking, partial 5-HT 1A-agonist, anti-H 1 histamine, adrenolytic, and sigma 1 receptor agonist activities, since an original 2004 report is increasingly misused. Although some of its pharmacodynamics might explain some motives for voluptuary use, most of its actions are directed at setting-off those motives. Hence, it is possible that its popularity in special populations is due to the fact that the unpleasant or unwanted effects of addiction substances are somehow soothed by quetiapine. Currently, quetiapine is tested in substance use disorders, showing some promise, but it is likely to be misused in certain contexts. Objectives: To review the evidence for the use of quetiapine as addiction substance and investigate the characteristics of populations involved in such addiction. Methods: A systematic review of literature on various databases retrieved on September 7, 2018 87 records to comment. Results. We reviewed the evidence for quetiapine's addictive potential in the light of its pharmacodynamics properties and presented two cases of recreational quetiapine use, by a 35-year old male patient with past addictive behavior and by a 50-year-old woman with major depressive disorder and conversion disorder. We found quetiapine to be abused mainly by addict populations and people with law involvement. Conclusions/Importance: There is no reason to include quetiapine among regulated substances, but monitoring of its use in selected populations is warranted. Psychiatrists and physicians working in the penitentiary system should be aware of the addictive potential of quetiapine and adopt measures restricting its use.
Substance Abuse: Research and Treatment
Background: Second-generation antipsychotics (SGAs) are assumed to have little abuse potential. However, reports of quetiapine abuse have emerged as prescribing has increased in recent years. The US Food and Drug Administration’s (FDA) Adverse Event Reporting System (FAERS) provides postmarketing information regarding adverse drug events (ADEs). This is the first study to analyze quetiapine abuse-related ADEs reported to FAERS to determine whether a disproportionate rate of such events have been reported when compared with other commonly used SGAs. Methods: A cross-sectional analysis of FAERS data from January 1, 2015, to December 31, 2017, was performed. The total number of all-cause and abuse-related ADEs reported to FAERS regarding quetiapine, olanzapine, aripiprazole, and risperidone were identified, along with demographic and mortality data. The proportional reporting ratio (PRR) was calculated to assess disproportionate reporting of abuse-related adverse drug reactions between...
Dose-response and comparative efficacy and tolerability of quetiapine across psychiatric disorders
International Clinical Psychopharmacology, 2011
The atypical antipsychotic, quetiapine, is frequently prescribed on-label and off-label for the treatment of a variety of psychiatric disorders. As quetiapine has variable affinity for dozens of receptors, its clinical effects should also show a large variation as a function of dose and diagnostic category. This study attempts to elucidate the dose-response and comparative efficacy and tolerability (metabolic data) of quetiapine across psychiatric disorders. A systematic search was carried out in the electronic databases, PubMed and EMBASE, using the keywords 'quetiapine' and 'placebo'. Both monotherapy and add-on studies were included. A total of 41 studies were identified. In unipolar and bipolar depression, studies consistently found quetiapine to be effective versus placebo, at doses of approximately 150-300 and 300-600 mg per day, respectively. In bipolar mania, they consistently found quetiapine to be effective at doses of approximately 600 mg per day. In acute exacerbation of schizophrenia, the majority of studies found quetiapine to be effective at doses of approximately 600 mg per day; however, a few large studies found no difference versus placebo. In contrast, studies consistently found quetiapine to be more effective than placebo for stable schizophrenia. In obsessive-compulsive disorder, studies did not consistently find quetiapine to be effective at doses of approximately 300 mg per day. However, studies may have underestimated the efficacy of quetiapine for obsessive-compulsive disorder due to concomitant administration of antidepressants and the utilization of treatment-refractory patients. In generalized anxiety disorder, studies consistently found quetiapine to be effective at doses of approximately 150 mg per day. Finally, analysis of metabolic tolerability data suggests that even low doses of quetiapine may lead to increase in weight and triglycerides across psychiatric disorders. Interestingly, however, quetiapine-induced elevations in low-density lipoprotein and total cholesterol seem to be restricted to schizophrenia patients.
Quetiapine – efficacy in different domains
European Neuropsychopharmacology, 2001
Conventional treatment paradigms for schizophrenia have typically focused on reducing positive symptomatology; however, it is increasingly apparent that negative and cognitive symptoms are also important treatment targets. Cognitive function, in particular, is known to affect multiple outcome domains, including performance of basic daily activities, and social and occupational functioning. While traditional antipsychotics have little, or even a detrimental, effect on neurocognitive impairment in patients with schizophrenia, available data suggest that cognitive function may be improved during treatment with atypical antipsychotics. Quetiapine is a novel atypical antipsychotic with proven efficacy in schizophrenia across all domains. Results of well-controlled, double-blind, randomised studies show quetiapine to significantly improve cognitive function compared with treatment with haloperidol. Quetiapine has also been shown to be effective and well tolerated in patients particularly vulnerable to the extrapyramidal side effects (EPS) associated with conventional antipsychotics, making it well suited for use as first-line therapy.