Additional evidence of the abuse potential of quetiapine

Quetiapine withdrawal: A systematic review

OBJECTIVE

Withdrawal from psychoactive medication such as quetiapine is a well-documented phenomenon. Despite the extensive use of quetiapine, there have been few studies into the presence of discontinuation symptoms. We therefore performed a systematic review of published literature for evidence of quetiapine withdrawal or symptoms associated with discontinuation.

METHODS

We searched PubMed, Embase, CINAHL, Medline, Web of Science, PsycINFO for articles containing the terms 'Quetiapine' AND 'withdraw^$' OR 'discontinue^$'. We included all study types that reported on somatic withdrawal symptoms and had no language restrictions. We excluded studies where there was withdrawal from multiple medications or any other psychoactive substance, or where the only symptoms were psychological such as rebound psychosis or craving.

RESULTS

We included 13 papers, all of which were individual case reports. The quality of the individual case reports was sub-optimal, as assessed by the CARE Case Report Guidelines. There was an association between rapid cessation of quetiapine and onset of somatic symptoms such as nausea, vomiting, agitation, restlessness, diaphoresis, irritability, anxiety, dysphoria, sleep disturbance, insomnia, tachycardia, hypertension and dizziness. Three studies also reported the onset of a withdrawal dyskinesia characterised by abnormal choreiform movements as well as confusion and speech disturbance in some cases. However, these findings were limited by the number and quality of case reports identified.

CONCLUSION

Discontinuation symptoms are an uncommon side effect of quetiapine cessation, which may have clinical implications. Clinicians should therefore be alert to the possibility of quetiapine withdrawal in individuals who present with somatic symptoms or choreiform movements. However, large prospective studies are required to clarify this association.

Neutropenia in Incarcerated Adolescents Secondary to Intranasal Quetiapine Misuse

Objective: Between April 2015 and May 2016, a number of young males incarcerated at a Youth Justice center in New South Wales, Australia, were noted to have unexplained and significant neutropenia. None of the adolescents were prescribed quetiapine; however, it was prescribed for other young people in the center for this time period. The authors undertook a case series review to investigate the cause of this neutropenia. Methods: Case series review, including review of all pathology, electrocardiograms, medication charts, and medical file notes. Results: Quetiapine was used in the center; however, none of the young people with neutropenia were prescribed quetiapine (or any other medication causing neutropenia). During the assessments of these young people, it was found that the administration of quetiapine had changed during this time period to using pulverized quetiapine powder, administered after hours to young people when there were no health center staff available to supervise. On questioning, two neutropenic young people admitted to "snorting" diverted quetiapine powder. All instances of neutropenia resolved once the medication was removed from the center. Conclusions: Quetiapine has a high potential for abuse, especially in custodial settings. Quetiapine should never be crushed as this increases the potential for diversion, misuse, and serious side effects. Quetiapine misuse should be considered part of the differential diagnosis of unexplained neutropenia, especially in a setting where the drug is available.

The Conceptual Framework of Dual Disorders and Its Flaws

When psychiatric illness and substance use disorder coexist, the clinical approach to the patient is, unsurprisingly, awkward. This fact is due to a cultural context and, more directly, to the patient's psychiatric condition and addiction behaviors-a situation that does not favor a scientific approach. In dual disorder facilities, several types of professionals work together: counselors, social workers, psychologists, and psychiatrists. Treatment approaches vary from one service to another and even within the same service. It is crucial to provide dual disorder patients with multiple treatments, comprising hospitalization, rehabilitative and residential programs, case management, and counselling. Still, when treating dual disorder (DD) heroin use disorder (HUD) patients, it is advisable to follow a hierarchical algorithm. First, we must deal with addiction: by detoxification, whenever possible. This means starting most patients on anti-craving pharmacological maintenance, though aversion therapy may be appropriate for a few of them. Opiate antagonists may be used with heroin-addicted patients as long as those patients are only mildly ill. In contrast, agonist opioid medications, i.e., buprenorphine and methadone suit moderately and severely ill patients, respectively. Achieving control of mood instability or psychotic episodes is the next step, to be followed by a prevention strategy to counteract residual cravings and dominate mood disorders or psychotic episodes through long-term pharmacological maintenance that is focused on a double target.

Effects of quetiapine on behavioral changes and expression of myelin proteins in a chronic alcohol dependence rat model

BACKGROUND

As an atypical antipsychotic drug, quetiapine had been approved for bipolar disorder and for adjunctive therapy in major depressive disorder and schizophrenia. Recently quetiapine has been suggested to be a promising pharmacotherapy for alcohol dependence. This study was performed to determine the effects of quetiapine in rats chronically exposed to ethanol.

METHODS

Rats were exposed to ethanol solution (10 %; v/v) for 6 weeks. Saline or one of three doses of quetiapine (10, 20 or 40 mg/kg/day) was given by oral gavage while ethanol exposure for the next 14 weeks. Performance of learning and memory and withdrawal signs were evaluated. Then immunohistochemistry, western blot, quantitative real-time-PCR and transmission electron microscopy were performed to determine the effects of quetiapine on alterations of brain white matter markers (myelin basic protein, MBP; proteolipid protein, PLP) and morphology caused by chronic ethanol exposure.

RESULTS

Quetiapine treatment significantly alleviated withdrawal signs in the ethanol exposed rats. Chronic ethanol exposure reduced Y-type electric maze scores and the protein/mRNA expression levels of MBP and PLP in the prefrontal cortex and hippocampus, and these effects were reversed by quetiapine treatment. Similar ultrastructure morphological changes were observed.

CONCLUSIONS

Chronic quetiapine treatment alleviated the damage induced by chronic ethanol exposure with regard to learning and memory ability and to brain white matter. Thus, quetiapine appears to be a potentially promising pharmacotherapy for the treatment of alcohol use disorder.

Quetiapine Abuse Fourteen Years Later: Where Are We Now? A Systematic Review

Background: Quetiapine, an atypical antipsychotic endowed with weak dopamine antagonist, potent 5-HT_2A-blocking, partial 5-HT_1A-agonist, anti-H₁ histamine, adrenolytic, and sigma₁ 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.

Abuse of Prescription Drugs in the Context of Novel Psychoactive Substances (NPS): A Systematic Review

Recently, a range of prescription and over-the-counter drugs have been reportedly used as Novel Psychoactive Substances (NPS), due to their potential for abuse resulting from their high dosage/idiosyncratic methods of self-administration. This paper provides a systematic review of the topic, focusing on a range of medications which have emerged as being used recreationally, either on their own or in combination with NPS. Among gabapentinoids, pregabalin may present with higher addictive liability levels than gabapentin, with pregabalin being mostly identified in the context of opioid, polydrug intake. For antidepressants, their dopaminergic, stimulant-like, bupropion activities may explain their recreational value and diversion from the therapeutic intended use. In some vulnerable clients, a high dosage of venlafaxine (‘baby ecstasy’) is ingested for recreational purposes, whilst the occurrence of a clinically-relevant withdrawal syndrome may be a significant issue for all venlafaxine-treated patients. Considering second generation antipsychotics, olanzapine appears to be ingested at very large dosages as an ‘ideal trip terminator’, whilst the immediate-release quetiapine formulation may possess proper abuse liability levels. Within the image- and performance- enhancing drugs (IPEDs) group, the beta-2 agonist clenbuterol (‘size zero pill’) is reported to be self-administered for aggressive slimming purposes. Finally, high/very high dosage ingestion of the antidiarrhoeal loperamide has shown recent increasing levels of popularity due to its central recreational, anti-withdrawal, opiatergic effects. The emerging abuse of prescription drugs within the context of a rapidly modifying drug scenario represents a challenge for psychiatry, public health and drug-control policies.

Is There a Potential of Misuse for Quetiapine?: Literature Review and Analysis of the European Medicines Agency/European Medicines Agency Adverse Drug Reactions' Database

PURPOSE/BACKGROUND

A recent years' increase in both prescribing and availability of second-generation antipsychotics (SGAs) has been observed. According to the literature, typically made up by case studies/series, quetiapine seems to be the most commonly misused SGA, with both intranasal and intravenous intake modalities having been described. Another SGA that has been anecdotally reported to be misused is olanzapine. For these molecules, both a previous history of drug misuse and being an inmate have been described as factors associated with misuse. Hence, while providing here an updated literature review of the topic, we aimed at assessing all cases of quetiapine misuse/abuse/dependence/withdrawal as reported to the European Medicines Agency's EudraVigilance (EV) database; this was carried out in comparison with the reference drug olanzapine.

METHODS

All spontaneous, European Medicines Agency database reports relating to both quetiapine (2005-2016) and olanzapine (2004-2016) misuse/abuse/dependence/withdrawal issues were retrieved, and a descriptive analysis was performed.

RESULTS

From the EV database, 18,112 (8.64% of 209,571) and 4178 (7.58% of 55,100) adverse drug reaction reports of misuse/abuse/dependence/withdrawal were associated with quetiapine and olanzapine, respectively. The resulting proportional reporting ratio values suggested that the misuse/abuse-, dependence-, and withdrawal-related adverse drug reactions were more frequently reported for quetiapine (1.07, 1.01, and 5.25, respectively) in comparison with olanzapine.

CONCLUSIONS

Despite data collection limitations, present EV data may suggest that, at least in comparison with olanzapine, quetiapine misuse may be a cause for concern.

Managing interactions between cognitive enhancers and other psychotropics

Polypharmacy is common in psychiatry. Usage of cognitive enhancers is increasing in the psychiatric population. Many clinicians are not familiar with these new psychoactive compounds. This paper reviews the potential drug-drug interactions when these cognitive enhancers are used together with psychotropic drugs and their confounding effects on diagnosis and clinical management.

Intentional Recreational Abuse of Quetiapine Compared to Other Second-generation Antipsychotics

INTRODUCTION

Case reports and poison center data have demonstrated that the second-generation antipsychotic quetiapine is being obtained and used for recreational abuse. The purpose of this study was to describe the relative rates of single-substance abuse for different atypical antipsychotics and compare their demographic and clinical features.

METHODS

We conducted a 10-year retrospective analysis of the National Poison Data System (NPDS) database (2003 - 2013). Trained nurses and pharmacists with specialty training in toxicology prospectively collect all NPDS data at poison control centers around the United States. We queried the NPDS for all cases of single-substance second-generation antipsychotic exposures coded as "intentional abuse." The data provided by the NPDS regarding rates and clinical features of quetiapine abuse and the abuse of all other second-generation antipsychotics were compared and described descriptively.

RESULTS

During the study period, 2,118 cases of quetiapine abuse and 1,379 cases of other second-generation antipsychotic abuse were identified. Quetiapine abuse was more common than the abuse of other second-generation antipsychotics, compromising 60.6% of all abuse cases during the study period. After quetiapine, the next most frequently abused medications were risperidone (530 cases, 15.2%) and olanzapine (246 cases, 7.0%). For all second-generation antipsychotics including quetiapine, central nervous system clinical effects were most common, including drowsiness, confusion, and agitation. Other serious clinical effects observed with second-generation antipsychotic abuse included hypotension, respiratory depression, and seizures.

CONCLUSION

Quetiapine abuse is relatively common, and is abused far more often than any other second-generation antipsychotic. Emergency physicians should be aware of the clinical effects that may occur after second-generation antipsychotic abuse.

Non-medical use of olanzapine by people on methadone treatment

Aims and method We examined non-medical use (NMU) of olanzapine among adults on methadone treatment. Information was collected on patient demographics and NMU of olanzapine. The Alcohol, Smoking and Substance Involvement Screening Test (ASSIST) was administered to assess risk among current users of olanzapine. Results Ninety-two clients participated and 30% reported lifetime history of NMU of olanzapine. Nine people reported doses of 30 mg or higher on a typical day of use, with three typically using 100 mg. The most common reasons for use were to relieve anxiety and to aid sleep, but a quarter used it to 'get stoned'. Eleven participants (12%) reported NMU of olanzapine in the preceding month. Eight completed the ASSIST with four scoring in the high-risk zone. Clinical implications Self-medication is the dominant motivator for NMU of olanzapine, but hedonic motivations also occur. A small minority show features of dependency. All doctors should be aware of the potential NMU of olanzapine, especially among patients with history of addiction.

Evaluation of the Reinforcing Effect of Quetiapine, Alone and in Combination with Cocaine, in Rhesus Monkeys

There are several case reports of nonmedicinal quetiapine abuse, yet there are very limited preclinical studies investigating quetiapine self-administration. The goal of this study was to investigate the reinforcing effects of quetiapine alone and in combination with intravenous cocaine in monkeys. In experiment 1, cocaine-experienced female monkeys (N = 4) responded under a fixed-ratio (FR) 30 schedule of food reinforcement (1.0-g banana-flavored pellets), and when responding was stable, quetiapine (0.003-0.1 mg/kg per injection) or saline was substituted for a minimum of five sessions; there was a return to food-maintained responding between doses. Next, monkeys were treated with quetiapine (25 mg, by mouth, twice a day) for approximately 30 days, and then the quetiapine self-administration dose-response curve was redetermined. In experiment 2, male monkeys (N = 6) self-administered cocaine under a concurrent FR schedule with food reinforcement (three food pellets) as the alternative to cocaine (0.003-0.3 mg/kg per injection) presentation. Once choice responding was stable, the effects of adding quetiapine (0.03 or 0.1 mg/kg per injection) to the cocaine solution were examined. In experiment 1, quetiapine did not function as a reinforcer, and chronic quetiapine treatment did not alter these effects. In experiment 2, cocaine choice increased in a dose-dependent fashion. The addition of quetiapine to cocaine resulted in increases in low-dose cocaine choice and number of cocaine injections in four monkeys, while not affecting high-dose cocaine preference. Thus, although quetiapine alone does not have abuse potential, there was evidence of enhancement of the reinforcing potency of cocaine. These results suggest that the use of quetiapine in cocaine-addicted patients should be monitored.

[Abuse Liability of Quetiapine (Xeroquel®)]

OBJECTIVE

In recent years, there have been several reports in the literature concerning the misuse and abuse of quetiapine. The aim of this study was to review the data reported to the French Network of the Addictovigilance Centers as well as the published data.

METHODS

Epidemiological data from the studies of French network addictovigilance centers (spontaneous notifications, suspicious presciptions suggesting possible abuse [ ordonnances suspectes indicateur d'abus possibles, OSIAP], observatory of illegal psychotropic substances or delivered substances diverted from their medicinal use survey [observation des produits psychotropes illicites ou détournées de leur utilisation médicamenteuse, OPPIDUM], deaths related to medication and substance abuse survey [décès en relation avec l'abus de médicaments et de substances, DRAMES]) were analyzed between 2011 and 2014. All cases of abuse and dependence with quetiapine in PubMed were reviewed using the MeSH terms "quetiapine," "substances abuse," and "dependence", until October 2014.

RESULTS

The analysis of the literature has identified 21 cases of abuse related to quetiapine, mainly in men (85.7%), with a history of substance abuse (76%). The main route of administration was oral but other routes were also reported (intravenous, intranasal). The main reason for abuse was sedation and anxiolytic. Other characteristics of quetiapine abuse include amplification or even simulation of psychotic symptoms to obtain quetiapine, an increased dose and the existence of street names. The French addictovigilance network reported few cases of abuse with quetiapine.

DISCUSSION-CONCLUSION

The pharmacological mechanism of abuse of quetiapine is not fully understood. However, several arguments are in favor of the abuse liability of quetiapine. Despite the recent availability of quetiapine in France, there have been some isolated signals of abuse. Therefore, it seems important to inform prescribers on the risk of misuse of quetiapine and also of some other antipsychotics.

Olanzapine as the ideal "trip terminator"? Analysis of online reports relating to antipsychotics' use and misuse following occurrence of novel psychoactive substance-related psychotic symptoms

OBJECTIVE

The pharmacological self-management of novel psychoactive substance (NPS)-induced psychopathological consequences represents a fast growing phenomenon. This is facilitated by the frequent sharing of NPS intake experiences online and by the ease of access to a range of psychotropic medications from both the online and street market. Olanzapine is anecdotally reported by Web users to be the most frequent self-prescribed medication to cope with NPS-induced psychoses. Hence, we aimed here at better assessing olanzapine use/misuse for this purpose.

METHODS

Exploratory qualitative searches of 163 discussion fora/specialized websites have been carried out in four languages (English, German, Spanish, and Italian) in the time frame November 2012-2013.

RESULTS

Most NPS-users allegedly self administer with olanzapine to manage related psychotic crises/"bad trips". This may be typically taken only for a few days, at a dosage range of 5-50 mg/day.

CONCLUSIONS

Only a few research studies have formally assessed the effectiveness of olanzapine and indeed of other second-generation antipsychotics to treat NPS-induced psychosis. Olanzapine was suggested here from a range of pro drug websites as being the "ideal" molecule to terminate "bad trips". Health professionals should be informed about the risks related to olanzapine misuse.

Concerns about quetiapine

Quetiapine is subsidised by the Pharmaceutical Benefits Scheme to treat schizophrenia and bipolar disorder. An extended-release formulation is also approved for use, but not subsidised, for treatment-resistant depression and generalised anxiety disorder. There is increasing off-label prescribing of quetiapine for indications such as insomnia that have little evidence to support them. This prescribing is often for at-risk patients, such as people with personality or social vulnerabilities and those at risk of metabolic complications or cardiovascular events. More evidence is required to support prescribing decisions regarding these off-label indications. In the meantime prescribers should be supported with alternatives to prescribing for these conditions, such as psychological therapies that have a better evidence base and safety record.

Evaluation of quetiapine abuse and misuse reported to poison centers

OBJECTIVE

There are case reports of abuse of quetiapine, but no studies address quetiapine abuse or misuse. Most literature on the population that abuses quetiapine describes an older age group with previous substance abuse history, many of whom are in jail. The objective of this study was to evaluate national poison center data on misuse/abuse of quetiapine.

METHODS

A retrospective study of American Association of Poison Control Centers National Poison Data System data from 2005 to 2011 on single substance quetiapine exposures coded as intentional misuse or abuse and followed to known outcome was performed. Data were evaluated for age, toxicity, management sites, treatments, and medical outcomes.

RESULTS

There were 3116 cases meeting inclusion criteria; reason was misuse in 1948 cases and abuse in 1168 cases. The median age was 23 years. Misuse was reported most often in adults, whereas abuse occurred most frequently in adolescents. The male-to-female ratio was 1.7 for abuse and 1.0 for misuse. There were no deaths. Moderate or major toxicity occurred in 23.7% and 27.1% of misuse and abuse cases, respectively. Seventy-six percent were treated in the emergency department and/or received medical admission.

CONCLUSIONS

Misuse was more common than abuse, except in adolescents for whom abuse was more frequent. Although outcomes were generally good, significant toxicity occurred in 25% of cases and more than 75% of the patients were treated in the emergency department and/or received medical admission. The consequences of nonmedical use of quetiapine are serious in some patients.

Effects of quetiapine treatment on cocaine self-administration and behavioral indices of sleep in adult rhesus monkeys

RATIONALE

Clinical literature suggests a link between substance abuse and sleep disturbances. Quetiapine, an atypical antipsychotic, has shown efficacy in treating sleep disturbances, with clinical studies showing promise for quetiapine as a treatment for cocaine abuse.

OBJECTIVE

The goal of this study was to examine the effects of quetiapine on cocaine self-administration and behavioral indices of sleep in monkeys.

METHODS

Seven adult male rhesus monkeys, fitted with Actical® activity monitors, were trained to respond under a choice paradigm of food (1.0-g pellets) and cocaine (0.003-0.3 mg/kg per injection) presentation. First, monkeys received acute pretreatment (45 min) with quetiapine (25-75 mg, p.o.) prior to choice sessions; three cocaine doses were studied in combination with quetiapine. Next, the effect of chronic (14-16 days) quetiapine treatment (25-250 mg, p.o., BID) was examined in combination with the lowest preferred cocaine dose (≥80 % cocaine choice). Behavioral indices of sleep, based on activity measures obtained during lights-out, were recorded throughout the study.

RESULTS

Acute quetiapine decreased cocaine choice in four of the seven monkeys. Chronic quetiapine treatment resulted in initial decreases in cocaine choice, but tolerance developed to these effects. Acute doses of quetiapine did not improve sleep efficiency the following night nor did chronic quetiapine. The first night after discontinuing quetiapine treatment resulted in significant decreases in sleep efficiency and increases in nighttime activity.

CONCLUSIONS

These findings do not offer support for the use of quetiapine as a monotherapy for treatment of cocaine abuse nor as an adjunct therapy to treat sleep disturbances associated with stimulant abuse.

The effect of quetiapine (Seroquel™) on conditioned place preference and elevated plus maze tests in rats when administered alone and in combination with (+)-amphetamine

RATIONALE

Recent case reports describe recreational use of quetiapine and drug-seeking behaviour to obtain quetiapine, an atypical antipsychotic.

OBJECTIVE

We examined the hypothesis that quetiapine (10, 20 or 40 mg/kg) alone or co-administered with (+)-amphetamine (0.25, 0.5, 0.75 or 2.0 mg/kg) will affect reward and/or decrease anxiety in rats, as measured by conditioned place preference (CPP) and elevated plus maze (EPM) test, respectively.

RESULTS

Quetiapine (20 mg/kg) produced greater open arm time and entries in the EPM test compared to 10 and 40 mg/kg, and quetiapine (10 mg/kg) significantly increased open arm entries and time when co-administered with (+)-amphetamine (0.5 mg/kg) compared to (+)-amphetamine (0.5 mg/kg) alone, suggesting decreased anxiety. Quetiapine (10, 20 or 40 mg/kg) produced no CPP when administered alone; the lowest dose of quetiapine (10 mg/kg) reduced CPP produced by a low dose of (+)-amphetamine (0.25 mg/kg), but had no significant effect on CPP produced by a higher dose (0.5 mg/kg).

DISCUSSION

The quetiapine-induced anxiolytic effect in the EPM might explain why humans are misusing quetiapine and combining it with (+)-amphetamine. It is possible that humans experience an anxiolytic effect of the combined drugs and relatively unaltered rewarding effects of (+)-amphetamine. The results shed some light on the question of why humans are abusing and misusing quetiapine, despite its dopamine (DA) D2 receptor antagonism; it will be the task of future studies to identify the pharmacological mechanism mediating this behaviour.

Olanzapine abuse

Olanzapine is a thienobenzodiazepine that blocks especially the serontonin (5-hydroxytryptamine [5-HT]) 5-HT2A and the dopamine D2 receptors as well as muscarinic (M1), histamine (H1), 5-HT2C, 5-HT3 to 5-HT6, adrenergic (α(l)), and D4 receptors. This case report presents an olanzapine abuse. A 48-year-old, primary school graduate, married woman applied to psychiatry clinic with tachycardia, insomnia, and anxiety complaints. In psychiatric evaluations, it was determined that these complaints have been continuing for 15 years at intervals and that she has been using citalopram 40 mg/day and olanzapine 50 mg/day for the last 3 years. As diabetes mellitus was diagnosed in follow-ups, interruption of olanzapine treatment was planned. The patient stated that she started taking the medicine again upon discomfort, increase in anxiety, dysphoria, insomnia, and nervousness, which started just after olanzapine was interrupted. She said that she was feeling dense stress when she did not take the medicine, and she thought that this situation would recover only by taking that medicine and hence she could not discontinue the medicine. In addition to medications with obvious abuse potential such as benzodiazepines and methylphenidate, and other stimulants, abuse of a number of commonly prescribed psychiatric medications has been reported. There are only 2 cases of olanzapine abuse in literature.

Acute dyskinesia, myoclonus, and akathisa in an adolescent male abusing quetiapine via nasal insufflation: a case study

BACKGROUND

Although the benefits of antipsychotic pharmacotherapy can be pronounced, many patients develop unwanted adverse effects including a variety of movement disorders. Compared with the traditional antipsychotics, the atypical antipsychotics have a decreased risk for associated movement disorders. Drug-induced movement disorders can occur, however, and the risk of adverse events can increase significantly when medications are abused.

CASE PRESENTATION

We describe the case of a 13-year-old male who presented to an emergency department with acute movement disorders after nasal insufflation of crushed quetiapine. The patient was admitted and successfully treated for neuroleptic toxicity with intravenous antihistamine pharmacotherapy. His primary care provider and psychiatrist were notified of the abuse, quetiapine was discontinued, and the patient was discharged and referred to a drug and alcohol awareness and abuse program.

CONCLUSIONS

The abuse of quetiapine has unfortunately become more common. This unique case report of acute movement disorders following nasal insufflation of quetiapine highlights the need for heightened vigilance when prescribing quetiapine and for increased awareness and education regarding medication-abuse.

The role of antihistaminic effects in the misuse of quetiapine: a case report and review of the literature

Recent case reports and case series suggest that the atypical antipsychotic quetiapine has the potential for misuse. This includes drug-seeking behaviors motivated by quetiapine as well as inappropriate (intranasal or intravenous) administration. We present an additional case of quetiapine misuse and review other published cases. In general, quetiapine misuse is associated with prior CNS depressant use and is more common in forensic settings. The mechanism of reinforcement for this misuse is unknown, but we hypothesize that it is related to quetiapine's pharmacological profile as an antihistamine with a relative low affinity for dopamine receptors. The risks to individuals and society of exaggerating/simulating symptoms to obtain high-dose quetiapine in the absence of a clinical indication are discussed. This includes the unwelcome possibility of restricting access to this effective medication.

Practical guidelines for the use of new generation antipsychotic drugs (except clozapine) in adult individuals with intellectual disabilities

New generation antipsychotic (NGA) drugs introduced to the US market after clozapine (aripiprazole, olanzapine, paliperidone, quetiapine, risperidone, and ziprasidone) are frequently used in individuals with intellectual disabilities (ID). However, there is very limited research to fully establish evidence-based or personalized medicine approaches for their use in this population. These guidelines take a pragmatic approach to establishing frameworks for their use by utilizing the prescribing information and reviewing the available literature on other relevant neuropsychiatric disorders. In the absence of expert consensus guidance and well-controlled comparison trials, we present a set of guidelines to inform initiation, dosing and monitoring of use in adults. Further, in these guidelines we provide practical information on drug-drug interactions and adverse drug reactions, and a brief review of discontinuation syndromes, potential for abuse, use during pregnancy and cost considerations. We also provide drug utilization review forms for each NGA to facilitate implementation of these guidelines, these guidelines provide a practical and necessary resource for practitioners treating psychiatric disorders and challenging behaviors in adult individuals with ID.

Using molecular similarity to highlight the challenges of routine immunoassay-based drug of abuse/toxicology screening in emergency medicine

Background

Laboratory tests for routine drug of abuse and toxicology (DOA/Tox) screening, often used in emergency medicine, generally utilize antibody-based tests (immunoassays) to detect classes of drugs such as amphetamines, barbiturates, benzodiazepines, opiates, and tricyclic antidepressants, or individual drugs such as cocaine, methadone, and phencyclidine. A key factor in assay sensitivity and specificity is the drugs or drug metabolites that were used as antigenic targets to generate the assay antibodies. All DOA/Tox screening immunoassays can be limited by false positives caused by cross-reactivity from structurally related compounds. For immunoassays targeted at a particular class of drugs, there can also be false negatives if there is failure to detect some drugs or their metabolites within that class.

Methods

Molecular similarity analysis, a computational method commonly used in drug discovery, was used to calculate structural similarity of a wide range of clinically relevant compounds (prescription and over-the-counter medications, illicit drugs, and clinically significant metabolites) to the target ('antigenic') molecules of DOA/Tox screening tests. These results were compared with cross-reactivity data in the package inserts of immunoassays marketed for clinical testing. The causes for false positives for phencyclidine and tricyclic antidepressant screening immunoassays were investigated at the authors' medical center using gas chromatography/mass spectrometry as a confirmatory method.

Results

The results illustrate three major challenges for routine DOA/Tox screening immunoassays used in emergency medicine. First, for some classes of drugs, the structural diversity of common drugs within each class has been increasing, thereby making it difficult for a single assay to detect all compounds without compromising specificity. Second, for some screening assays, common 'out-of-class' drugs may be structurally similar to the target compound so that they account for a high frequency of false positives. Illustrating this point, at the authors' medical center, the majority of positive screening results for phencyclidine and tricyclic antidepressants assays were explained by out-of-class drugs. Third, different manufacturers have adopted varying approaches to marketed immunoassays, leading to substantial inter-assay variability.

Conclusion

The expanding structural diversity of drugs presents a difficult challenge for routine DOA/Tox screening that limit the clinical utility of these tests in the emergency medicine setting.

Is quetiapine a drug of abuse? Reexamining the issue of addiction

BACKGROUND

The abuse and diversion of pharmacological agents with CNS mechanisms of action is an important concern from governmental, regulatory, public health and safety perspectives. In recent years, there have been an increased number of reports concerning the abuse and diversion of quetiapine in forensic population and in individuals with histories of substance abuse.

OBJECTIVE

To better understand this surging pattern the available body of evidence was critically examined.

METHODS

A literature search from January 1991 to July 2008 restricting papers to English and using PUBMED and PsychInfo was performed.

RESULTS

Nine papers were identified. The content of these papers is discussed in light of recent research on drug abuse.