Methamphetamine toxicity: treatment with a benzodiazepine versus a butyrophenone

Pharmacological Treatments for Methamphetamine Use Disorder: Current Status and Future Targets

The illicit use of the psychostimulant methamphetamine (METH) is a major concern, with overdose deaths increasing substantially since the mid-2010s. One challenge to treating METH use disorder (MUD), as with other psychostimulant use disorders, is that there are no available pharmacotherapies that can reduce cravings and help individuals achieve abstinence. The purpose of the current review is to discuss the molecular targets that have been tested in assays measuring the physiological, the cognitive, and the reinforcing effects of METH in both animals and humans. Several drugs show promise as potential pharmacotherapies for MUD when tested in animals, but fail to produce long-term changes in METH use in dependent individuals (eg, modafinil, antipsychotic medications, baclofen). However, these drugs, plus medications like atomoxetine and varenicline, may be better served as treatments to ameliorate the psychotomimetic effects of METH or to reverse METH-induced cognitive deficits. Preclinical studies show that vesicular monoamine transporter 2 inhibitors, metabotropic glutamate receptor ligands, and trace amine-associated receptor agonists are efficacious in attenuating the reinforcing effects of METH; however, clinical studies are needed to determine if these drugs effectively treat MUD. In addition to screening these compounds in individuals with MUD, potential future directions include increased emphasis on sex differences in preclinical studies and utilization of pharmacogenetic approaches to determine if genetic variances are predictive of treatment outcomes. These future directions can help lead to better interventions for treating MUD.

Co-exposure to gamma-hydroxybutyrate is associated with attenuated neuropsychiatric and stimulant effects of metamfetamine

INTRODUCTION

Acute metamfetamine toxicity is characterized by stimulant effects and neuropsychiatric disturbance, which is attenuated by gamma-aminobutyric acid type A receptor agonists including benzodiazepines. We utilized clinical registry data to examine the effect of co-exposure to a gamma-aminobutyric acid type B receptor agonist (gamma-hydroxybutyrate) in illicit drug cases with analytically confirmed exposure to metamfetamine.

METHODS

The Emerging Drugs Network of Australia Victoria is an ethics board-approved prospective registry collecting clinical and analytical data (utilising blood samples) on emergency department illicit drug presentations. Comparison groups were defined by analytically confirmed exposure: lone metamfetamine, metamfetamine plus gamma-hydroxybutyrate, metamfetamine plus benzodiazepine, metamfetamine plus gamma-hydroxybutyrate plus benzodiazepine. Cases with co-exposure to other stimulants or sedatives were excluded.

RESULTS

Median metamfetamine blood concentrations were significantly greater in metamfetamine plus gamma-hydroxybutyrate (n = 153, median = 0.20 mg/L, interquartile range: 0.10-0.32 mg/L, 95 per cent confidence interval: 0.20-0.23 mg/L) and metamfetamine plus gamma-hydroxybutyrate plus benzodiazepine (n = 160, median = 0.20 mg/L, interquartile range: 0.10-0.30 mg/L, 95 per cent confidence interval: 0.20-0.30 mg/L) positive groups compared to gamma-hydroxybutyrate negative groups including metamfetamine (n = 81, median = 0.10 mg/L, interquartile range: 0.05-0.21 mg/L, 95 per cent confidence interval: 0.09-0.18 mg/L) and metamfetamine plus benzodiazepine (n = 73, median = 0.10 mg/L, interquartile range: 0.06-0.20 mg/L, 95 per cent confidence interval: 0.09-0.20 mg/L) groups (P < 0.0004). Presenting heart rate in metamfetamine plus gamma-hydroxybutyrate cases (n = 153, median = 72 beats per minute, interquartile range: 63-86 beats per minute, 95 per cent confidence interval: 70-78 beats per minute) was significantly lower than metamfetamine plus benzodiazepine cases (n = 73, median = 84 beats per minute, interquartile range: 73-98 beats per minute, 95 per cent confidence interval: 80-90 beats per minute, P < 0.0001), and lone metamfetamine cases (n = 81, median = 110 beats per minute, interquartile range: 87-131 beats per minute, 95 per cent confidence interval: 93-120 beats per minute, P < 0.0001). Presenting temperature in metamfetamine plus gamma-hydroxybutyrate cases (median = 35.8 °C, interquartile range: 35.0-36.2 °C, 95 per cent confidence interval 35.6-35.9 °C) was significantly lower than metamfetamine plus benzodiazepine cases (median 36.2 °C, interquartile range 35.7-36.6 °C, 95 per cent confidence interval, 36.0-36.4 °C, P = 0.017), and lone metamfetamine cases (median = 36.5 °C, interquartile range: 35.8-37.1 °C, 95 per cent confidence interval: 36.2-36.7 °C, P < 0.0001). Median presenting systolic blood pressure was significantly (P ≤ 0.001) lower in benzodiazepine positive groups (metamfetamine plus benzodiazepine median = 120 mmHg, interquartile range: 109-132 mmHg, 95 per cent confidence interval: 116-124 mmHg and metamfetamine plus benzodiazepine plus gamma-hydroxybutyrate median = 124 mmHg, interquartile range: 110-137 mmHg, 95 per cent confidence interval: 120-129 mmHg). Incidence of sedation (Glasgow Coma Scale less than 9) was significantly greater in metamfetamine plus gamma-hydroxybutyrate cases (63 per cent) compared to metamfetamine plus benzodiazepine cases (27 per cent, P < 0.0001) and lone metamfetamine cases (15 per cent, P < 0.0001). Incidence of agitation was significantly lower in metamfetamine plus gamma-hydroxybutyrate plus benzodiazepine cases (17 per cent, P < 0.0001) and metamfetamine plus gamma-hydroxybutyrate cases (34 per cent, P = 0.0004) compared to lone metamfetamine cases (58 per cent).

DISCUSSION

Differences in gamma-aminobutyric acid type A and B receptor physiology may offer a gamma-aminobutyric acid type B agonist-facilitated alternative pharmacodynamic mechanism able to attenuate metamfetamine stimulant and neuropsychiatric toxicity.

CONCLUSION

Metamfetamine intoxicated patients with analytically confirmed co-exposure to gamma-hydroxybutyrate had significantly reduced heart rate, body temperature and incidence of agitation compared to patients with lone metamfetamine exposure. Metamfetamine intoxicated patients with analytically confirmed co-exposure to a benzodiazepine had significantly reduced systolic blood pressure compared to patients with lone metamfetamine exposure. We hypothesize that gamma-aminobutyric acid type B receptor agonists may be beneficial in the management of acute metamfetamine toxicity.

Methamphetamine Toxicities and Clinical Management

Methamphetamine Toxicities and Clinical ManagementMethamphetamine increases the release and blocks the uptake of norepinephrine, serotonin, and dopamine. This article reviews the morbidity and mortality associated with methamphetamine use and discusses prevention and treatment strategies.

2023 American Heart Association Focused Update on the Management of Patients With Cardiac Arrest or Life-Threatening Toxicity Due to Poisoning: An Update to the American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care

In this focused update, the American Heart Association provides updated guidance for resuscitation of patients with cardiac arrest, respiratory arrest, and refractory shock due to poisoning. Based on structured evidence reviews, guidelines are provided for the treatment of critical poisoning from benzodiazepines, β-adrenergic receptor antagonists (also known as β-blockers), L-type calcium channel antagonists (commonly called calcium channel blockers), cocaine, cyanide, digoxin and related cardiac glycosides, local anesthetics, methemoglobinemia, opioids, organophosphates and carbamates, sodium channel antagonists (also called sodium channel blockers), and sympathomimetics. Recommendations are also provided for the use of venoarterial extracorporeal membrane oxygenation. These guidelines discuss the role of atropine, benzodiazepines, calcium, digoxin-specific immune antibody fragments, electrical pacing, flumazenil, glucagon, hemodialysis, hydroxocobalamin, hyperbaric oxygen, insulin, intravenous lipid emulsion, lidocaine, methylene blue, naloxone, pralidoxime, sodium bicarbonate, sodium nitrite, sodium thiosulfate, vasodilators, and vasopressors for the management of specific critical poisonings.

Are Histamine H3 Antagonists the Definitive Treatment for Acute Methamphetamine Intoxication?

BACKGROUND

Methamphetamine (METH) is classified as a Schedule II stimulant drug under the United Nations Convention on Psychotropic Substances of 1971. METH and other amphetamine analogues (AMPHs) are powerful addictive drugs. Treatments are needed to treat the symptoms of METH addiction, chronic METH use, and acute METH overdose. No effective treatment for METH abuse has been established because alterations of brain functions under the excessive intake of abused drug intake are largely irreversible due in part to brain damage that occurs in the course of chronic METH use.

OBJECTIVE

Modulation of brain histamine neurotransmission is involved in several neuropsychiatric disorders, including substance use disorders. This review discusses the possible mechanisms underlying the therapeutic effects of histamine H₃ receptor antagonists on symptoms of methamphetamine abuse.

CONCLUSION

Treatment of mice with centrally acting histamine H₃ receptor antagonists increases hypothalamic histamine contents and reduces high-dose METH effects while potentiating lowdose effects via histamine H₃ receptors that bind released histamine. On the basis of experimental evidence, it is hypothesized that histamine H₃ receptors may be an effective target for the treatment METH use disorder or other adverse effects of chronic METH use.

Randomized Double-blind Trial of Intramuscular Droperidol, Ziprasidone, and Lorazepam for Acute Undifferentiated Agitation in the Emergency Department

BACKGROUND

The optimal agent to treat acute agitation in the emergency department (ED) has not been determined. The objective of this study was to compare the effectiveness and safety of intramuscular droperidol, ziprasidone, and lorazepam for acute agitation in the ED.

METHODS

This was a randomized, double-blind trial of ED patients with acute agitation requiring parenteral sedation. The study was conducted under exception from informed consent (21 CFR 50.24) from July 2004 to March 2005. Patients were randomized to receive 5 mg of droperidol, 10 mg of ziprasidone, 20 mg of ziprasidone, or 2 mg of lorazepam intramuscularly. We recorded Altered Mental Status Scale (AMSS) scores, nasal end-tidal carbon dioxide (ETCO₂ ), and pulse oximetry (SpO₂ ) at 0, 15, 30, 45, 60, 90, and 120 minutes as well as QTc durations and dysrhythmias. Respiratory depression was defined as a change in ETCO₂ consistent with respiratory depression or SpO₂  < 90%. The primary outcome was the proportion of patients adequately sedated (AMSS ≤ 0) at 15 minutes.

RESULTS

We enrolled 115 patients. Baseline AMSS scores were similar between groups. For the primary outcome, adequate sedation at 15 minutes, droperidol administration was effective in 16 of 25 (64%) patients, compared to seven of 28 (25%) for 10 mg of ziprasidone, 11 of 31 (35%) for 20 mg of ziprasidone, and nine of 31 (29%) for lorazepam. Pairwise comparisons revealed that droperidol was more effective that the other medications, with 39% (95% confidence interval [CI] = 3% to 54%) more compared to 20 mg of ziprasidone and 33% (95% CI = 8% to 58%) more compared to lorazepam. There was no significant difference between groups in need of additional rescue sedation. Numerically, respiratory depression was lower with droperidol (3/25 [12%]) compared to 10 mg of ziprasidone (10/28 [36%]), 20 mg of ziprasidone (12/31 [39%]), or lorazepam (15/31 [48%]). One patient receiving 20 mg of ziprasidone required intubation to manage an acute subdural hematoma. No patients had ventricular dysrhythmias. QTc durations were similar in all groups.

CONCLUSIONS

Droperidol was more effective than lorazepam or either dose of ziprasidone for the treatment of acute agitation in the ED and caused fewer episodes of respiratory depression.

Safety and efficacy of pharmacologic agents used for rapid tranquilization of emergency department patients with acute agitation or excited delirium

Introduction: Management of patients with acute agitation or aggressive behavior can pose a significant challenge to health-care providers in emergency departments. Areas covered: This article provides a comprehensive review of the pharmacologic properties, efficacy, and safety profiles of select intramuscular (IM) sedative agents (i.e., antipsychotics, benzodiazepines, and ketamine) for rapid tranquilization. Expert opinion: Using antipsychotics and benzodiazepines - whether a single agent or combined - will have similar efficacy in producing sedation. But there are differences in the time to sedation depending on which agent is used. Based upon the available studies, droperidol (5-10 mg IM) and midazolam (5-10 mg IM) have the fastest onset of sedation when either is used as a single agent. When combination therapy is used, using midazolam with an antipsychotic agent, instead of lorazepam, may result in faster sedative effect. QT prolongation and torsades de pointes are uncommon adverse drug effects of antipsychotic administration. Ketamine is often reserved as a second-line agent when antipsychotics and benzodiazepines fail to produce the desired tranquilization. However, ketamine (5 mg/kg IM) is more frequently associated with airway compromise requiring endotracheal intubation. A low-dose of ketamine (2 mg/kg IM) may reduce the risk of airway compromise while providing adequate sedation.

Risk Factors for Sedation-related Events During Acute Agitation Management in the Emergency Department

OBJECTIVE

The objective was to describe the incidence, nature, and risk factors for adverse events (AEs) among patients who received parenteral sedation for acute agitation in an emergency department (ED) setting.

METHODS

We undertook a prospective observational study and a clinical trial of parenteral sedation for the management of acute agitation. We included agitated adult patients who required parenteral sedation from 2014 to 2017 in 12 Australian EDs, excluding those with incomplete information or aged under 18 years. The primary outcome was the number of patients who experienced at least one AE. Multivariable logistic regression was used to determine factors associated with AEs.

RESULTS

A total of 904 patients were included in the analyses (62.3% male; median age = 34 years, range = 18 to 95 years). Of these, 144 (15.9%) patients experienced at least one AE. The most common AEs were oxygen desaturation (7.4%), airway obstruction (3.6%), bradycardia (1.9%), hypotension (1.7%), and prolonged QTc interval (1.3%). No deaths or serious AEs were reported. The following factors had an increased adjusted odds ratio (OR) for experiencing an AE: age 65 years and older (OR = 2.8, 95% confidence interval [CI] = 1.2 to 7.2), more than one type of parenteral sedation administered within 60 minutes (OR = 2.1, 95% CI = 1.4 to 3.1), and alcohol intoxication (OR = 1.8, 95% CI = 1.2 to 2.6).

CONCLUSIONS

Sedation-related AEs are common, especially respiratory events. Elderly patients, sedation with multiple sedatives within 60 minutes, and alcohol intoxication increased the risk.

Methamphetamine: Putting the Brakes on Speed

In only recent history, illicit use of methamphetamine, once isolated to urban areas on the West Coast, has spread into rural areas of the Midwest and southern United States. Although past and current methamphetamine legislation has increased penalties for methamphetamine manufacturers and tightened restrictions on sales of known precursors, the problem still persists. In fact, a 2004 survey indicates that an alarming 6.2% of high school seniors have tried methamphetamine. A number of biological, genetic, and environmental factors influence children's and adolescents’ paths to substance abuse. Nurses should recognize the symptoms of methamphetamine abuse, which include agitation; aggressive behavior; rapid mood swings; hypertension; tachycardia; and eventually lesion-marked skin, clinical depression, and paranoid psychosis. Treatment for methamphetamine addiction includes behavioral therapy. Research on pharmacologic therapy is lacking. Educating youth on methamphetamine prevention appears to be the best approach to curb the spreading use of this addictive and deadly drug.

Methamphetamine Use and Emergency Department Utilization: 20 Years Later

Background

Methamphetamine (MAP) users present to the emergency department (ED) for myriad reasons, including trauma, chest pain, and psychosis. The purpose of this study is to determine how their prevalence, demographics, and resource utilization have changed.

Methods

Retrospective review of MAP patients over 3 months in 2016. Demographics, mode of arrival, presenting complaints, disposition, and concomitant cocaine/ethanol use were compared to a 1996 study at the same ED.

Results

638 MAP-positive patients, 3,013 toxicology screens, and 20,203 ED visits represented an increase in prevalence compared to 1996: 461 MAP-positive patients, 3,102 screens, and 32,156 visits. MAP patients were older compared to the past. Mode of arrival was most frequently by ambulance but at a lower proportion than 1996, as was the proportion of MAP patients with positive cocaine toxicology screens and ethanol coingestion. Admission rate was lower compared to the past, as was discharge to jail. The proportion of MAP patients presenting with blunt trauma was lower compared to the past and higher for chest pain.

Conclusion

A significant increase in the prevalence of MAP-positive patients was found. Differences in presenting complaints and resource utilization may reflect the shifting demographics of MAP users, as highlighted by an older patient population relative to the past.

Intravenous midazolam-droperidol combination, droperidol or olanzapine monotherapy for methamphetamine-related acute agitation: subgroup analysis of a randomized controlled trial

AIM

To examine the efficacy and safety of (1) midazolam-droperidol versus droperidol and (2) midazolam-droperidol versus olanzapine for methamphetamine-related acute agitation.

DESIGN AND SETTING

A multi-centre, randomized, double-blind, controlled, clinical trial was conducted in two Australian emergency departments, between October 2014 and September 2015.

PARTICIPANTS

Three hundred and sixty-one patients, aged 18-65 years, requiring intravenous medication sedation for acute agitation, were enrolled into this study. We report the results of a subgroup of 92 methamphetamine-affected patients.

INTERVENTION AND COMPARATOR

Patients were assigned randomly to receive either an intravenous bolus of midazolam 5 mg-droperidol 5 mg combined, droperidol 10 mg or olanzapine 10 mg. Two additional doses were administered, if required: midazolam 5 mg, droperidol 5 mg or olanzapine 5 mg, respectively.

MEASUREMENTS

The primary outcome was the proportion of patients sedated adequately at 10 minutes. Odds ratios with 95% confidence intervals (ORs, 95% CI) were estimated.

FINDINGS

The baseline characteristics of patients in the three groups were similar. At 10 minutes, significantly more patients in the midazolam-droperidol group [29 of 34 (85.3%)] were sedated adequately compared with the droperidol group [14 of 30 (46.7%), OR = 6.63, 95% CI = 2.02-21.78] or with the olanzapine group [14 of 28 (50.0%), OR 5.80, 95% CI = 1.74-19.33]. The number of patients who experienced an adverse event (AE) in the midazolam-droperidol, droperidol and olanzapine groups was seven of 34, two of 30 and six of 28, respectively. The most common AE was oxygen desaturation.

CONCLUSION

A midazolam-droperidol combination appears to provide more rapid sedation of patients with methamphetamine-related acute agitation than droperidol or olanzapine alone.

Droperidol for psychosis-induced aggression or agitation

BACKGROUND

People experiencing acute psychotic illnesses, especially those associated with agitated or violent behaviour, may require urgent pharmacological tranquillisation or sedation. Droperidol, a butyrophenone antipsychotic, has been used for this purpose in several countries.

OBJECTIVES

To estimate the effects of droperidol, including its cost-effectiveness, when compared to placebo, other 'standard' or 'non-standard' treatments, or other forms of management of psychotic illness, in controlling acutely disturbed behaviour and reducing psychotic symptoms in people with schizophrenia-like illnesses.

SEARCH METHODS

We updated previous searches by searching the Cochrane Schizophrenia Group Register (18 December 2015). We searched references of all identified studies for further trial citations and contacted authors of trials. We supplemented these electronic searches by handsearching reference lists and contacting both the pharmaceutical industry and relevant authors.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) with useable data that compared droperidol to any other treatment for people acutely ill with suspected acute psychotic illnesses, including schizophrenia, schizoaffective disorder, mixed affective disorders, the manic phase of bipolar disorder or a brief psychotic episode.

DATA COLLECTION AND ANALYSIS

For included studies, we assessed quality, risk of bias and extracted data. We excluded data when more than 50% of participants were lost to follow-up. For binary outcomes, we calculated standard estimates of risk ratio (RR) and the corresponding 95% confidence intervals (CI). We created a 'Summary of findings' table using GRADE.

MAIN RESULTS

We identified four relevant trials from the update search (previous version of this review included only two trials). When droperidol was compared with placebo, for the outcome of tranquillisation or asleep by 30 minutes we found evidence of a clear difference (1 RCT, N = 227, RR 1.18, 95% CI 1.05 to 1.31, high-quality evidence). There was a clear demonstration of reduced risk of needing additional medication after 60 minutes for the droperidol group (1 RCT, N = 227, RR 0.55, 95% CI 0.36 to 0.85, high-quality evidence). There was no evidence that droperidol caused more cardiovascular arrhythmia (1 RCT, N = 227, RR 0.34, 95% CI 0.01 to 8.31, moderate-quality evidence) and respiratory airway obstruction (1 RCT, N = 227, RR 0.62, 95% CI 0.15 to 2.52, low-quality evidence) than placebo. For 'being ready for discharge', there was no clear difference between groups (1 RCT, N = 227, RR 1.16, 95% CI 0.90 to 1.48, high-quality evidence). There were no data for mental state and costs.Similarly, when droperidol was compared to haloperidol, for the outcome of tranquillisation or asleep by 30 minutes we found evidence of a clear difference (1 RCT, N = 228, RR 1.01, 95% CI 0.93 to 1.09, high-quality evidence). There was a clear demonstration of reduced risk of needing additional medication after 60 minutes for participants in the droperidol group (2 RCTs, N = 255, RR 0.37, 95% CI 0.16 to 0.90, high-quality evidence). There was no evidence that droperidol caused more cardiovascular hypotension (1 RCT, N = 228, RR 2.80, 95% CI 0.30 to 26.49,moderate-quality evidence) and cardiovascular hypotension/desaturation (1 RCT, N = 228, RR 2.80, 95% CI 0.12 to 67.98, low-quality evidence) than haloperidol. There was no suggestion that use of droperidol was unsafe. For mental state, there was no evidence of clear difference between the efficacy of droperidol compared to haloperidol (Scale for Quantification of Psychotic Symptom Severity, 1 RCT, N = 40, mean difference (MD) 0.11, 95% CI -0.07 to 0.29, low-quality evidence). There were no data for service use and costs.Whereas, when droperidol was compared with midazolam, for the outcome of tranquillisation or asleep by 30 minutes we found droperidol to be less acutely tranquillising than midazolam (1 RCT, N = 153, RR 0.96, 95% CI 0.72 to 1.28, high-quality evidence). As regards the 'need for additional medication by 60 minutes after initial adequate sedation, we found an effect (1 RCT, N = 153, RR 0.54, 95% CI 0.24 to 1.20, moderate-quality evidence). In terms of adverse effects, we found no statistically significant differences between the two drugs for either airway obstruction (1 RCT, N = 153, RR 0.13, 95% CI 0.01 to 2.55, low-quality evidence) or respiratory hypoxia (1 RCT, N = 153, RR 0.70, 95% CI 0.16 to 3.03, moderate-quality evidence) - but use of midazolam did result in three people (out of around 70) needing some sort of 'airway management' with no such events in the droperidol group. There were no data for mental state, service use and costs.Furthermore, when droperidol was compared to olanzapine, for the outcome of tranquillisation or asleep by any time point, we found no clear differences between the older drug (droperidol) and olanzapine (e.g. at 30 minutes: 1 RCT, N = 221, RR 1.02, 95% CI 0.94 to 1.11, high-quality evidence). There was a suggestion that participants allocated droperidol needed less additional medication after 60 minutes than people given the olanzapine (1 RCT, N = 221, RR 0.56, 95% CI 0.36 to 0.87, high-quality evidence). There was no evidence that droperidol caused more cardiovascular arrhythmia (1 RCT, N = 221, RR 0.32, 95% CI 0.01 to 7.88, moderate-quality evidence) and respiratory airway obstruction (1 RCT, N = 221, RR 0.97, 95% CI 0.20 to 4.72, low-quality evidence) than olanzapine. For 'being ready for discharge', there was no difference between groups (1 RCT, N = 221, RR 1.06, 95% CI 0.83 to 1.34, high-quality evidence). There were no data for mental state and costs.

AUTHORS' CONCLUSIONS

Previously, the use of droperidol was justified based on experience rather than evidence from well-conducted and reported randomised trials. However, this update found high-quality evidence with minimal risk of bias to support the use of droperidol for acute psychosis. Also, we found no evidence to suggest that droperidol should not be a treatment option for people acutely ill and disturbed because of serious mental illnesses.

Population pharmacokinetics of intramuscular droperidol in acutely agitated patients

BACKGROUND

Intramuscular droperidol is used increasingly for sedation of aggressive and violent patients. This study aimed to characterise the pharmacokinetics of intramuscular droperidol in these patients to determine how rapidly it is absorbed and the expected duration of measurable drug concentrations.

METHODS

We undertook a population pharmacokinetic analysis of a subgroup of patients from a clinical trial comparing droperidol and midazolam: 17 receiving 5 mg and 24 receiving 10 mg droperidol. Droperidol was measured using high-performance liquid chromatography. Pharmacokinetic modelling was performed under a nonlinear mixed effects modelling framework (NONMEM v7.2). The model was used to simulate concentration time profiles of three typical doses, 5 mg, 10 mg and 10 mg + 10 mg repeated at 15 min.

RESULTS

A two-compartment first-order input with first-order output model fitted the data best. The absorption rate constant was poorly characterised by the data and an estimate of the first order rate constant of absorption when fixed to 10 h^-1 provided a stable model and lowest objective function. This represents extremely rapid absorption with a half-life of 5 min. The final model had a clearance of 41.9 l h^-1 and volume of distribution of the central compartment of, 73.6 l. Median and interquartile range of initial (alpha) half-life was 0.32 h (0.26-0.37 h) and second (beta) half-life was 3.0 h (2.5-3.6 h). Simulations indicate that 10 mg alone provides an 80% probability of being above the lower limit of quantification (5 μg l^-1 ) for 7 h, 2 h longer than for 5 mg. Giving two 10 mg doses increased this duration to 10 h.

CONCLUSIONS

Intramuscular droperidol is rapidly absorbed with high therapeutic concentrations after 5 and 10 mg doses, and supports clinical data in which droperidol sedates rapidly for up to 6 h.

Assessment and management of agitation in psychiatry: Expert consensus

BACKGROUND

Psychomotor agitation is associated with different psychiatric conditions and represents an important issue in psychiatry. Current recommendations on agitation in psychiatry are not univocal. Actually, an improper assessment and management may result in unnecessary coercive or sedative treatments. A thorough and balanced review plus an expert consensus can guide assessment and treatment decisions.

METHODS

An expert task force iteratively developed consensus using the Delphi method. Initial survey items were based on systematic review of the literature. Subsequent surveys included new, re-worded or re-rated items.

RESULTS

Out of 2175 papers assessing psychomotor agitation, 124 were included in the review. Each component was assigned a level of evidence. Integrating the evidence and the experience of the task force members, a consensus was reached on 22 statements on this topic.

CONCLUSIONS

Recommendations on the assessment of agitation emphasise the importance of identifying any possible medical cause. For its management, experts agreed in considering verbal de-escalation and environmental modification techniques as first choice, considering physical restraint as a last resort strategy. Regarding pharmacological treatment, the "ideal" medication should calm without over-sedate. Generally, oral or inhaled formulations should be preferred over i.m. routes in mildly agitated patients. Intravenous treatments should be avoided.

Treatment of toxicity from amphetamines, related derivatives, and analogues: a systematic clinical review

BACKGROUND

Overdose of amphetamine, related derivatives, and analogues (ARDA) continues to be a serious worldwide health problem. Patients frequently present to the hospital and require treatment for agitation, psychosis, and hyperadrenegic symptoms leading to pathologic sequelae and mortality.

OBJECTIVE

To review the pharmacologic treatment of agitation, psychosis, and the hyperadrenergic state resulting from ARDA toxicity.

METHODS

MEDLINE, PsycINFO, and the Cochrane Library were searched from inception to September 2014. Articles on pharmacologic treatment of ARDA-induced agitation, psychosis, and hyperadrenergic symptoms were selected. Evidence was graded using Oxford CEBM. Treatment recommendations were compared to current ACCF/AHA guidelines.

RESULTS

The search resulted in 6082 articles with 81 eligible treatment involving 835 human subjects. There were 6 high-quality studies supporting the use of antipsychotics and benzodiazepines for control of agitation and psychosis. There were several case reports detailing the successful use of dexmedetomidine for this indication. There were 9 high-quality studies reporting the overall safety and efficacy of β-blockers for control of hypertension and tachycardia associated with ARDA. There were 3 high-quality studies of calcium channel blockers. There were 2 level I studies of α-blockers and a small number of case reports for nitric oxide-mediated vasodilators.

CONCLUSIONS

High-quality evidence for pharmacologic treatment of overdose from ARDA is limited but can help guide management of acute agitation, psychosis, tachycardia, and hypertension. The use of butyrophenone and later-generation antipsychotics, benzodiazepines, and β-blockers is recommended based on existing evidence. Future randomized prospective trials are needed to evaluate new agents and further define treatment of these patients.

The clinical toxicology of metamfetamine

INTRODUCTION

Metamfetamine is a highly addictive amfetamine analog that acts primarily as a central nervous system (CNS) stimulant. The escalating abuse of this drug in recent years has lead to an increasing burden upon health care providers. An understanding of the drug's toxic effects and their medical treatment is therefore essential for the successful management of patients suffering this form of intoxication.

AIM

The aim of this review is to summarize all main aspects of metamfetamine poisoning including epidemiology, mechanisms of toxicity, toxicokinetics, clinical features, diagnosis, and management.

METHODS

A summary of the literature on metamfetamine was compiled by systematically searching OVID MEDLINE and ISI Web of Science. Further information was obtained from book chapters, relevant news reports, and web material. Epidemiology. Following its use in the Second World War, metamfetamine gained popularity as an illicit drug in Japan and later the United States. Its manufacture and use has now spread to include East and South-East Asia, North America, Mexico, and Australasia, and its world-wide usage, when combined with amfetamine, exceeds that of all other drugs of abuse except cannabis. Mechanisms of toxicity. Metamfetamine acts principally by stimulating the enhanced release of catecholamines from sympathetic nerve terminals, particularly of dopamine in the mesolimbic, mesocortical, and nigrostriatal pathways. The consequent elevation of intra-synaptic monoamines results in an increased activation of central and peripheral α±- and β-adrenergic postsynaptic receptors. This can cause detrimental neuropsychological, cardiovascular, and other systemic effects, and, following long-term abuse, neuronal apoptosis and nerve terminal degeneration. Toxicokinetics. Metamfetamine is rapidly absorbed and well distributed throughout the body, with extensive distribution across high lipid content tissues such as the blood-brain barrier. In humans the major metabolic pathways are aromatic hydroxylation producing 4-hydroxymetamfetamine and N-demethylation to form amfetamine. Metamfetamine is excreted predominantly in the urine and to a lesser extent by sweating and fecal excretion, with reported terminal half-lives ranging from ∼5 to 30 h. Clinical features. The clinical effects of metamfetamine poisoning can vary widely, depending on dose, route, duration, and frequency of use. They are predominantly characteristic of an acute sympathomimetic toxidrome. Common features reported include tachycardia, hypertension, chest pain, various cardiac dysrhythmias, vasculitis, headache, cerebral hemorrhage, hyperthermia, tachypnea, and violent and aggressive behaviour. Management. Emergency stabilization of vital functions and supportive care is essential. Benzodiazepines alone may adequately relieve agitation, hypertension, tachycardia, psychosis, and seizure, though other specific therapies can also be required for sympathomimetic effects and their associated complications.

CONCLUSION

Metamfetamine may cause severe sympathomimetic effects in the intoxicated patient. However, with appropriate, symptom-directed supportive care, patients can be expected to make a full recovery.

A review of the clinical pharmacology of methamphetamine

AIMS

To examine the literature regarding clinical pharmacokinetics, direct effects and adverse clinical outcomes associated with methamphetamine use.

METHODS

Relevant literature was identified through a PubMed search. Additional literature was obtained from relevant books and monographs.

FINDINGS AND CONCLUSIONS

The mean elimination half-life for methamphetamine is approximately 10 hours, with considerable inter-individual variability in pharmacokinetics. Direct effects at low-to-moderate methamphetamine doses (5-30 mg) include arousal, positive mood, cardiac stimulation and acute improvement in cognitive domains such as attention and psychomotor coordination. At higher doses used typically by illicit users (> or =50 mg), methamphetamine can produce psychosis. Its hypertensive effect can produce a number of acute and chronic cardiovascular complications. Repeated use may induce neurotoxicity, associated with prolonged psychiatric symptoms, cognitive impairment and an increased risk of developing Parkinson's disease. Abrupt cessation of repeated methamphetamine use leads to a withdrawal syndrome consisting of depressed mood, anxiety and sleep disturbance. Acute withdrawal lasts typically for 7-10 days, and residual symptoms associated with neurotoxicity may persist for several months.

Treatment for amphetamine psychosis

BACKGROUND

Chronic amphetamine users may have experience of paranoia and hallucination. It has long been believed that dopamine antagonists, such as chlorpromazine, haloperidol, and thioridazine, are effective for the treatment of amphetamine psychosis.

OBJECTIVES

To evaluate risks, benefits, costs of treatments for amphetamine psychosis.

SEARCH STRATEGY

MEDLINE (1966-2007), EMBASE (1980-2007), CINAHL (1982-2007), PsychINFO (1806-2007), CENTRAL (Cochrane Library 2008 issue 1), references of obtained articles.

SELECTION CRITERIA

All randomised controlled and clinical trials (RCTs, CCTs) evaluating treatments (alone or combined) for people with amphetamine psychosis

DATA COLLECTION AND ANALYSIS

Two authors evaluated and extracted the data independently. Dichotomous data were extracted on an intention-to-treat basis in which the dropouts were assigned as participants with the worst outcomes. The Relative Risk (RR) with the 95% confidence interval (95% CI) was used to assess the dichotomous data. The Weighted Mean Difference (WMD) with 95% CI was used to assess the continuous data.

MAIN RESULTS

The comprehensive searches found one randomised controlled trial of treatment for amphetamine psychosis meeting the criteria for considering studies. The study involved 58 participants and compared the efficacy and tolerability of two antipsychotic drugs, olanzapine (a newer antipsychotic) and haloperidol (a commonly used antipsychotic medication used as a control condition), in treating amphetamine-induced psychosis. The results show that both olanzapine and haloperidol at clinically relevant doses were efficacious in resolving psychotic symptoms, with the olanzapine condition showing significantly greater safety and tolerability than the haloperidol control as measured by frequency and severity of extrapyramidal symptoms.

AUTHORS' CONCLUSIONS

Only one RCT of treatment for amphetamine psychosis has been published. Outcomes from this trial indicate that antipsychotic medications effectively reduce symptoms of amphetamine psychosis, the newer generation and more expensive antipsychotic medication, olanzapine, demonstrates significantly better tolerability than the more affordable and commonly used medication, haloperidol.There are other two studies that did not meet the inclusion criteria for this review. The results of these two studies show that agitation and some psychotic symptoms may be abated within an hour after antipsychotic injection.Whether this limited evidence can be applied for amphetamine psychotic patients is not yet known.The medications that should be further investigate are conventional antipsychotics, newer antipsychotics and benzodiazepines. However, naturalistic studies of amphetamine psychotic symptoms and the prevalence of relapse to psychosis in the presence of amphetamine, are also crucial for advising the development of study designs appropriate for further treatment studies of amphetamine psychosis.

Treatment for amphetamine psychosis

BACKGROUND

Chronic amphetamine users may have experience of paranoia and hallucination. It has long been believed that dopamine antagonists, such as chlorpromazine, haloperidol, and thioridazine, are effective for the treatment of amphetamine psychosis.

OBJECTIVES

To evaluate risks, benefits, costs of treatments for amphetamine psychosis.

SEARCH STRATEGY

MEDLINE (1966-2007), EMBASE (1980-2007), CINAHL (1982-2007), PsychINFO (1806-2007), CENTRAL (Cochrane Library 2008 issue 1), references of obtained articles.

SELECTION CRITERIA

All randomised controlled and clinical trials (RCTs, CCTs) evaluating treatments (alone or combined) for people with amphetamine psychosis

DATA COLLECTION AND ANALYSIS

Two authors evaluated and extracted the data independently. Dichotomous data were extracted on an intention-to-treat basis in which the dropouts were assigned as participants with the worst outcomes. The Relative Risk (RR) with the 95% confidence interval (95% CI) was used to assess the dichotomous data. The Weighted Mean Difference (WMD) with 95% CI was used to assess the continuous data.

MAIN RESULTS

The comprehensive searches found one randomised controlled trial of treatment for amphetamine psychosis meeting the criteria for considering studies. The study involved 58 participants and compared the efficacy and tolerability of two antipsychotic drugs, olanzapine (a newer antipsychotic) and haloperidol (a commonly used antipsychotic medication used as a control condition), in treating amphetamine-induced psychosis. The results show that both olanzapine and haloperidol at clinically relevant doses were efficacious in resolving psychotic symptoms, with the olanzapine condition showing significantly greater safety and tolerability than the haloperidol control as measured by frequency and severity of extrapyramidal symptoms.

AUTHORS' CONCLUSIONS

Only one RCT of treatment for amphetamine psychosis has been published. Outcomes from this trial indicate that antipsychotic medications effectively reduce symptoms of amphetamine psychosis, the newer generation and more expensive antipsychotic medication, olanzapine, demonstrates significantly better tolerability than the more affordable and commonly used medication, haloperidol.There are other two studies that did not meet the inclusion criteria for this review. The results of these two studies show that agitation and some psychotic symptoms may be abated within an hour after antipsychotic injection. Whether this limited evidence can be applied for amphetamine psychotic patients is not yet known.The medications that should be further investigate are conventional antipsychotics, newer antipsychotics and benzodiazepines. However, naturalistic studies of amphetamine psychotic symptoms and the prevalence of relapse to psychosis in the presence of amphetamine, are also crucial for advising the development of study designs appropriate for further treatment studies of amphetamine psychosis.

Dual intoxication with diazepam and amphetamine: This drug interaction probably potentiates myocardial ischemia

Drug-induced myocardial infarction is not a common phenomenon and the underlying mechanism has been related with the coronary artery spasm in the majority of cases. It is mainly related to illicit substances such as cocaine, ecstasy, LSD and amphetamine. According to the findings in the literature, it is most likely that myocardial ischemia due to amphetamine abuse is a result of combined mechanisms which include coronary artery vasospasm, and in lesser extent thrombus formation or direct myocardial toxicity. Diazepam is also usually found as a substance of abuse. Recent findings indicate that diazepam exerts an inhibitory activity on different isoforms of the enzyme cyclic nucleotide phosphodiesterase, which can be found in the heart muscle and also show that diazepam potentate the positive inotropic effect of both noradrenaline and adrenaline, which subsequently leads to increase in myocardial contractility. We propose that dual intoxication with amphetamine and benzodiazepine potentate their effects on cardiac tissue and coronary arteries which results in larger myocardial injury.

Clinical effects and management of methamphetamine abuse

Methamphetamine is a highly potent and addictive drug that is abused in the United States and around the world. The drug is inexpensive and easily manufactured from simple chemicals such as pseudoephedrine. These features, coupled with its long half-life and highly addictive nature, contribute to the increasing problem of illicit methamphetamine use. Abuse of this agent has both acute and chronic serious health consequences. Policy makers and public health officials must continue to develop programs that educate the public and limit the abuse associated with methamphetamine.

Pharmacologic treatment of acute pediatric methamphetamine toxicity

OBJECTIVE

To report our experience with the use of benzodiazepines and haloperidol for sedation of pediatric patients with acute methamphetamine poisoning.

METHODS

We performed a retrospective chart review of 18 pediatric patients who were admitted to an intensive care unit for methamphetamine toxicity from January 1997 to October 2004 and treated with benzodiazepines or haloperidol. Clinical features, dose of drug received, and laboratory test results were noted. Adverse effects from the use of haloperidol such as prolonged QTc, dystonic reactions, and torsades de pointes were recorded.

RESULTS

Eighteen patients received a benzodiazepine, the dose of which varied depending on the agent used. Twelve patients also received parenteral haloperidol. No complications developed from the use of either haloperidol or benzodiazepines.

CONCLUSIONS

In this case series of pediatric patients poisoned with methamphetamine, parenteral benzodiazepines and haloperidol were used to control agitation. No serious adverse effects were observed from the use of these agents.

The spectrum of informed consent in emergency psychiatric research

STUDY OBJECTIVE

I evaluate the variation in requirements for informed consent in studies evaluating chemical tranquilization of agitated patients.

METHODS

A computer-assisted literature search of the National Library of Medicine was performed. Additional use of the references listed in the articles identified with the search yielded 144 citations. Studies performed outside the United States were excluded, as were studies performed before the current US Food and Drug Administration regulations came into effect. Research not yet published but presented at national meetings was included, as was one study currently under way but otherwise meeting the inclusion criteria. Authors were contacted for further clarification in cases in which information was ambiguous or unavailable in print.

RESULTS

Twelve studies were identified, and the approach to informed consent varied widely. The primary method of enrollment was informed consent in 7 studies. Three studies used a waiver of informed consent, but in these cases the federal regulations underlying these waivers varied. One study implied that neither consent nor a waiver of consent was needed. In one case, the primary method for consent was not specified.

CONCLUSION

There is poor agreement about the application of current regulations about informed consent in emergency psychiatric research. Regulations are understood in such a variety of ways that they are effectively irrelevant. There needs to be much greater clarity about the use of waivers of informed consent in emergency research in general and emergency psychiatry in particular.

Droperidol for acute psychosis

BACKGROUND

People suffering from acute psychotic illnesses, especially those associated with agitated or violent behaviour, may require urgent pharmacological tranquillisation or sedation. Droperidol, a butyrophenone neuroleptic, has been used for this purpose in several countries.

OBJECTIVES

To estimate the effects of droperidol compared to other treatments for controlling disturbed behaviour and reducing psychotic symptoms for people with suspected acute psychotic illnesses.

SEARCH STRATEGY

We updated previous searches by searching the Cochrane Schizophrenia Group Register (September 2003). References of all identified studies were searched for further trial citations and authors of trials were contacted. Twenty-one other databases were also searched as part of a broader project and this composite database was searched for this review. This was supplemented by hand searching reference lists and contacting both the pharmacological industry and relevant authors.

SELECTION CRITERIA

The review included randomised controlled trials comparing droperidol to any other treatment for people with suspected acute psychotic illnesses, including schizophrenia, schizoaffective disorder, mixed affective disorders, the manic phase of bipolar disorder or a brief psychotic episode.

DATA COLLECTION AND ANALYSIS

Relevant studies were selected for inclusion, their quality was assessed and data extracted. Data were excluded when more than 50% of participants were lost to follow up. For binary outcomes, standard estimates of risk ratio (RR) and the corresponding 95% confidence intervals (CI) were calculated. Where possible, weighted number needed to treat or harm statistics (NNT, NNH), and the corresponding 95% confidence intervals (CI), were calculated.

MAIN RESULTS

We identified only two relevant trials. One additional study focused on outcomes at 30 days rather than at a few hours. One small (n = 41) randomised trial compared intravenous (iv) droperidol (10 mg) with iv placebo and found that people allocated to droperidol were significantly less likely to need additional injections of another drug, haloperidol, in the first few minutes (n = 41, RR 0.37 CI 0.2 to 0.7, NNT 2 CI 1 to 10) compared to those given placebo. By 90 minutes this difference was still evident but not statistically significant (RR 0.46 CI 0.2 to 1.2). When 5 mg intramuscular (im) droperidol was compared with 5 mg im haloperidol, those given droperidol were also less likely to need additional injections by 30 minutes, than those given haloperidol, but this result was not statistically significant (n = 27, RR 0.45 CI 0.2 to 1.01). One person out of the 16 given haloperidol experienced a mild dystonic reaction (muscle spasms or abnormal contractions), while none of the 11 people allocated to droperidol were reported to have experienced adverse effects.

REVIEWERS' CONCLUSIONS

This is an important, and surprisingly under-researched, area. To date, use of droperidol for emergency situations has been justified by experience rather than evidence from well conducted and reported randomised trials, but, as world reserves diminish, droperidol will no longer be a treatment option.

Street drug abuse leading to critical illness

Critical care physicians are frequently confronted with intoxicated patients who have used street drugs. In the last decade there has been an upward trend in the use of these substances, particularly amongst adolescents and young adults in large urban areas. In excess quantities all street drugs can lead to critical illness. Early and appropriate medical attention by emergency medicine physicians and intensivists can improve outcomes. In this review article we intend to familiarize critical care physicians with the most common street drugs such as amphetamines, ecstasy, cocaine, gamma hydroxybutyrate, opioids, and phencyclidine.

Toxicology in the critically ill patient

Intoxications present in many forms including: known drug overdose or toxic exposure, illicit drug use, suicide attempt, accidental exposure, and chemical or biological terrorism. A high index of suspicion and familiarity with toxidromes can lead to early diagnosis and intervention in critically ill, poisoned patients. Despite a paucity of evidence-based information on the management of intoxicated patients, a rational and systematic approach can be life saving.

Pharmacological management of agitation in emergency settings

OBJECTIVE

To review, firstly, published studies comparing classic antipsychotics, benzodiazepines, and/or combination of both; and secondly, available data on the use of atypical antipsychotic medications in controlling agitation and aggressive behaviour seen in psychiatric patients in emergency.

METHOD

In the first review, studies comparing antipsychotics, benzodiazepines, and combination of both; and in the second review, efficacy trials of atypical antipsychotics that include an active and/or inactive comparator for the treatment of acute agitation were identified and reviewed. Data from clinical trials meeting the inclusion criteria were summarised by recording improvement rates, definition of improvement, and timing of defined improvement for individual studies.

RESULTS

In the first review, 11 trials were identified meeting the inclusion criteria, eight with a blind design. The total number of subjects was 701. These studies taken together suggest that combination treatment may be superior to the either agent alone with higher improvement rates and lower incidence of extrapyramidal side effects. In the review of atypical antipsychotic agents as acute antiagitation compounds, five studies were identified, three with a blind design. The total number of subjects was 711, of which 15% (104) was assigned to the placebo arm. This review found atypical antipsychotics to be as effective as the classic ones and more advantageous in many aspects.

CONCLUSION

Atypical antipsychotics such as risperidone, ziprasidone, and olanzapine with or without benzodiazepines should be considered first in the treatment of acute agitation. If these agents are not available the combination of a classic antipsychotic and a benzodiazepine would be a reasonable alternative. An oral treatment should always be offered first for building up an alliance with the patient and suggesting an internal rather than external locus of control.

Droperidol, QT prolongation, and sudden death: what is the evidence?

STUDY OBJECTIVE

Droperidol is a butyrophenone commonly used as an antiemetic and antipsychotic in the United States since US Food and Drug Administration (FDA) approval in 1970. Its labeling has recently been revised, with a black box warning for cases of QT prolongation leading to torsades de pointes and death. A black box warning is applied when serious adverse drug reactions are uncovered for medications. We sought to examine the evidence of a causal association suggested by the black box warning to aid clinicians in their risk-benefit analyses regarding further use of droperidol.

METHODS

A literature search was undertaken to determine the evidence regarding the association between droperidol and QT prolongation or torsades de pointes. The evidence was then evaluated by using evidence-based medicine principles. In addition, a review of the FDA regulatory process is presented.

RESULTS

Three clinical studies, 1 published abstract, and 7 case reports were reviewed. Available postmarketing surveillance data (MedWatch reports) were also reviewed. Applying the criteria of evidence-based medicine and Hill's criteria, the evidence is not convincing for a causal relationship between therapeutic droperidol administration and life-threatening cardiac events.

CONCLUSION

The recent black box warning appears to have originated from postmarketing surveillance data rather than data reported in the peer-reviewed medical literature. Ongoing monitoring of drug safety and more definitive study appear appropriate.

Droperidol for acute psychosis

BACKGROUND

People with acute psychotic illnesses, especially when associated with agitated or violent behaviour, may require urgent pharmacological tranquillisation or sedation. Droperidol, a butyrophenone neuroleptic, is used for this purpose in several countries.

OBJECTIVES

To estimate the effects of droperidol when compared to other treatments for controlling disturbed behaviour and reducing psychotic symptoms for people with suspected acute psychotic illnesses.

SEARCH STRATEGY

The Cochrane Controlled Trials Register (Issue 2, 2000), The Cochrane Schizophrenia Group's Register (May 2000), EMBASE (1980-2000), MEDLINE (1966-2000), PASCAL (1973-2000) and PsycLIT (1970-2000) were methodically searched. Twenty-one other databases were also searched as part of a broader project and this composite database was searched for this review. This was supplemented by hand searching reference lists, contacting industry and relevant authors.

SELECTION CRITERIA

Randomised clinical trials comparing droperidol to any treatment, for people with suspected acute psychotic illnesses, such as schizophrenia, schizoaffective disorder, mixed affective disorders, manic phase of bipolar disorder or brief psychotic episode.

DATA COLLECTION AND ANALYSIS

Studies were reliably selected, quality assessed and data extracted. Data were excluded where more than 50% of participants were lost to follow up. For binary outcomes, standard estimations of risk ratio (RR) and their 95% confidence intervals (CI) were calculated. Where possible, weighted number needed to treat or harm statistics (NNT, NNH), and their 95% confidence intervals (CI), were also calculated.

MAIN RESULTS

Only two clearly relevant randomised trials with usable data were identified. One additional study was included but focused on outcomes at 30 days rather than a few hours. One small (n=41) randomised trial compared droperidol (10mg IV) with placebo IV and found that people allocated to droperidol were significantly less likely to need additional haloperidol injections in the first few minutes (n=41, RR 0.37 CI 0.2 to 0.7, NNT 2 CI 1 to 10) than those given placebo. By 90 minutes this difference was still evident but not statistically significant (RR 0.46 CI 0.2 to 1.2). When 5mg IM droperidol was compared to 5mg IM haloperidol people given droperidol were again less likely to need additional injections by 30 minutes, than those given haloperidol, but this result did not quite reach conventional levels of statistical significance (n=27, RR 0.45 CI 0.2 to 1.01). One person out of 16 given haloperidol experienced a mild dystonic reaction, and none of the 11 people allocated to droperidol were reported to have experienced adverse effects.

REVIEWER'S CONCLUSIONS

This is an important and surprisingly under-researched area. Use of droperidol for the emergency situation is currently justified on experience rather than evidence from well conducted and reported randomised trials.

Patterns of tooth wear associated with methamphetamine use

BACKGROUND

Methamphetamine (MAP) abuse is a significant worldwide problem. This prospective study was conducted to determine if MAP users had distinct patterns of tooth wear.

METHODS

Methamphetamine users were identified and interviewed about their duration and preferred route of MAP use. Study participants were interviewed in the emergency department of a large urban university hospital serving a geographic area with a high rate of illicit MAP production and consumption. Tooth wear was documented for each study participant and scored using a previously validated index and demographic information was obtained using a questionnaire.

RESULTS

Forty-three MAP patients were interviewed. Preferred route of administration was injection (37%) followed by snorting (33%). Patients who preferentially snorted MAP had significantly higher tooth wear in the anterior maxillary teeth than patients who injected, smoked, or ingested MAP (P = 0.005).

CONCLUSION

Patients who use MAP have distinct patterns of wear based on route of administration. This difference may be explained anatomically.

Rhabdomyolysis and drugs of abuse

Rhabdomyolysis is a disorder in which injury to muscle results in leakage of myocyte intracellular contents into the plasma. It has been associated with a tremendous number and diversity of clinical conditions and substances. Several physiological and biochemical mechanisms for this syndrome have been described. The most likely etiology of rhabdomyolysis in patients presenting to the emergency department is ingestion of drugs of abuse, most commonly ethanol, heroin, amphetamines, cocaine, and other sedatives or stimulants. In this article, the association between rhabdomyolysis and drugs of abuse is explored, as well as its diagnosis and treatment.

Phenomenology and treatment of psychotic disorders in the psychiatric emergency service

The emergency evaluation of a psychotic patient calls on all of the skills of the psychiatrist. The immediate control of dangerous behavior takes place at the same time that clinicians evaluate patients for delirium. A screening physical examination, a brief mental status examination, and a high index of suspicion for medical diseases are essential tools in the first few minutes of a patient's stay in the psychiatric emergency service. Drugs of abuse are often part of a patient's presentation. Here, too, the first task is to rule out delirium, particularly from sedative or alcohol withdrawal. As soon as a patient's condition is stabilized, the psychiatrist should review all of the available information, develop a working diagnosis, and initiate definitive treatment of the presumed disorder. With fewer emergency patients being hospitalized and with shorter lengths of hospital stay, these initial decisions acquire increasing significance for patient outcome.

Methamphetamine abuse and rhabdomyolysis in the ED: a 5-year study

Patients with methamphetamine toxicity are presenting in greater numbers each year to emergency departments (ED) in the US. These patients are frequently agitated, violent, and often require physical and chemical restraint. The incidence and risk of rhabdomyolysis in this subpopulation is unknown. We conducted a 5-year retrospective review of all ED patients who received the final diagnosis of rhabdomyolysis. Patients with toxicology screens positive for methamphetamine were identified, and demographics, laboratory results, resource utilization, disposition, and outcome were compared to the remaining patients. Of the total 367 patients identified, 166 (43%) were toxicology positive for methamphetamine. Methamphetamine patients differed significantly from nonmethamphetamine patients with regard to demographics and hospital utilization. Methamphetamine patients had significantly higher mean initial creatine phosphokinase (CK), 12,439 U/L versus 5,678 U/L (P = 0.02), and lower mean peak CK, 16,827 U/L versus 19,426 U/L (P = 0.03). The development of acute renal failure was not significantly different between the 2 groups. There were 16 total deaths in the study population, 11 from concomitant infection/sepsis. An association between methamphetamine abuse and rhabdomyolysis may exist, and CK should be measured in the ED as a screen for potential muscle injury in this subpopulation. Patients with rhabdomyolysis with an unclear cause should be screened for methamphetamine or other illicit drugs.