Liquid ecstasy: a new kid on the dance floor

[Damages to the central nervous system due to illicit drug use]

CLINICAL ISSUE

Illicit drugs can cause a myriad of CNS damages. The toxicity might be caused by the drug itself or by diverse contaminants. The most common changes are ischemic and hemorrhagic stroke as well as subarachnoid hemorrhage and leukoencephalopathies. This article gives a review of the most important morphological imaging findings of the CNS in illicit drug users.

PRACTICAL RECOMMENDATIONS

In cases of stroke or unclear leukoencephalopathies in young adults, the differential diagnosis of illicit drug use should be considered.

“Charging” and “Blowing Out”: Patterns and Cultures of GHB Use in Melbourne, Australia

Recent increases in the use of gamma hydroxybutyrate (GHB) in club and rave settings have been associated with a series of acute health problems including overdose. Drawing upon research recently completed in Melbourne, Australia among a sample of young club and rave patrons, this article explores the knowledge, attitudes and related “risk-behaviors” of individuals who use GHB, as well as the various cultures and contexts surrounding its use. A mixed quantitative and qualitative research design was utilized, comprising a detailed survey (N=923) and semistructured interviews (N=24). Almost all survey respondents reported to have consumed illicit drugs in the past, with around half reporting “lifetime” use of GHB. A quarter reported using GHB in the past year. GHB related harms were widely reported with 22% of GHB users reporting to have overdosed on the drug at least once. The article closes with recommendations for GHB specific prevention and harm reduction strategies.

The clinical toxicology of γ-hydroxybutyrate, γ-butyrolactone and 1,4-butanediol

INTRODUCTION

Gamma-hydroxybutyrate (GHB) and its precursors, gamma-butyrolactone (GBL) and 1,4-butanediol (1,4-BD), are drugs of abuse which act primarily as central nervous system (CNS) depressants. In recent years, the rising recreational use of these drugs has led to an increasing burden upon health care providers. Understanding their toxicity is therefore essential for the successful management of intoxicated patients. We review the epidemiology, mechanisms of toxicity, toxicokinetics, clinical features, diagnosis, and management of poisoning due to GHB and its analogs and discuss the features and management of GHB withdrawal.

METHODS

OVID MEDLINE and ISI Web of Science databases were searched using the terms "GHB," "gamma-hydroxybutyrate," "gamma-hydroxybutyric acid," "4-hydroxybutanoic acid," "sodium oxybate," "gamma-butyrolactone," "GBL," "1,4-butanediol," and "1,4-BD" alone and in combination with the keywords "pharmacokinetics," "kinetics," "poisoning," "poison," "toxicity," "ingestion," "adverse effects," "overdose," and "intoxication." In addition, bibliographies of identified articles were screened for additional relevant studies including nonindexed reports. Non-peer-reviewed sources were also included: books, relevant newspaper reports, and applicable Internet resources. These searches produced 2059 nonduplicate citations of which 219 were considered relevant.

EPIDEMIOLOGY

There is limited information regarding statistical trends on world-wide use of GHB and its analogs. European data suggests that the use of GHB is generally low; however, there is some evidence of higher use among some sub-populations, settings, and geographical areas. In the United States of America, poison control center data have shown that enquiries regarding GHB have decreased between 2002 and 2010 suggesting a decline in use over this timeframe.

MECHANISMS OF ACTION

GHB is an endogenous neurotransmitter synthesized from glutamate with a high affinity for GHB-receptors, present on both on pre- and postsynaptic neurons, thereby inhibiting GABA release. In overdose, GHB acts both directly as a partial GABA(b) receptor agonist and indirectly through its metabolism to form GABA.

TOXICOKINETICS

GHB is rapidly absorbed by the oral route with peak blood concentrations typically occurring within 1 hour. It has a relatively small volume of distribution and is rapidly distributed across the blood-brain barrier. GHB is metabolized primarily in the liver and is eliminated rapidly with a reported 20-60 minute half-life. The majority of a dose is eliminated completely within 4-8 hours. The related chemicals, 1,4-butanediol and gamma butyrolactone, are metabolized endogenously to GHB. CLINICAL FEATURES OF POISONING: GHB produces CNS and respiratory depression of relatively short duration. Other commonly reported features include gastrointestinal upset, bradycardia, myoclonus, and hypothermia. Fatalities have been reported. MANAGEMENT OF POISONING: Supportive care is the mainstay of management with primary emphasis on respiratory and cardiovascular support. Airway protection, intubation, and/or assisted ventilation may be indicated for severe respiratory depression. Gastrointestinal decontamination is unlikely to be beneficial. Pharmacological intervention is rarely required for bradycardia; however, atropine administration may occasionally be warranted. WITHDRAWAL SYNDROME: Abstinence after chronic use may result in a withdrawal syndrome, which may persist for days in severe cases. Features include auditory and visual hallucinations, tremors, tachycardia, hypertension, sweating, anxiety, agitation, paranoia, insomnia, disorientation, confusion, and aggression/combativeness. Benzodiazepine administration appears to be the treatment of choice, with barbiturates, baclofen, or propofol as second line management options.

CONCLUSIONS

GHB poisoning can cause potentially life-threatening CNS and respiratory depression, requiring appropriate, symptom-directed supportive care to ensure complete recovery. Withdrawal from GHB may continue for up to 21 days and can be life-threatening, though treatment with benzodiazepines is usually effective.

Sodium oxybate for the treatment of fibromyalgia

INTRODUCTION

Gamma-hydroxybutyrate (GHB) is a short-chain fatty acid that is synthesized within the CNS, mostly from its parent compound gamma amino butyric acid (GABA). GHB acts as a neuromodulator/neurotransmitter to affect neuronal activity of other neurotransmitters and so, stimulate the release of growth hormone. Its sodium salt (sodium oxybate: SXB) was approved by the Food and Drug Administration (FDA) for the treatment of narcolepsy. SXB has shown to improve disrupted sleep and increase NR3 (slow-wave restorative) sleep in patients with narcolepsy. It is rapidly absorbed and has a plasma half-life of 30 - 60 min, necessitating twice-nightly dosing. Most of the observed effects of SXB result from binding to GABA-B receptors.

AREAS COVERED

Several randomized, controlled trials demonstrated significantly improved fibromyalgia (FM) symptoms with SXB. As seen in narcolepsy trials, SXB improved sleep of FM patients, increased slow-wave sleep duration as well as delta power, and reduced frequent night-time awakenings. Furthermore, FM pain and fatigue was consistently reduced with nightly SXB over time. Commonly reported adverse events included headache, nausea, dizziness and somnolence. Despite its proven efficacy, SXB did not receive FDA approval for the management of FM in 2010, mostly because of concerns about abuse.

EXPERT OPINION

Insomnia, fatigue and pain are important clinical FM symptoms that showed moderate improvements with SXB in several large, well-designed clinical trials. Because of the limited efficacy of currently available FM drugs additional treatment options are needed. In particular, drugs like SXB - which belong to a different drug class than other Food and Drug Administration (FDA)-approved FM medications such as pregabalin, duloxetine and milnacipran - would provide a much-needed addition to presently available treatment options. However, the FDA has set the bar high for future SXB re-submissions, with requirements of superior efficacy and improved risk mitigation strategies. At this time, no future FDA submission of SXB for the fibromyalgia indication is planned.

The involvement of gamma-hydroxybutyrate in reported sexual assaults: a systematic review

Over the past few years gamma-hydroxybutyrate (GHB) has generated widespread media interest as a possible 'date rape drug'. Our goal was to examine the extent to which GHB is associated with drug-facilitated sexual assaults. Literature was searched systematically and 11 studies, published between 1961 and June 30, 2009, were identified dealing specifically with the role of GHB in sexual assaults. GHB was detected in 0.2-4.4% of reported sexual assaults. The results demonstrate that a wide range of drugs may be present in cases of sexual assault, and many of them are much more frequent than GHB. Our results do not support the widespread labelling of GHB as a date rape drug as the prevalence of GHB is much lower than of other substances used in sexual assaults. On the other hand, however, the possible risk of GHB in this regard should not be neglected. Nevertheless, over-sensitive and sensation seeking media reports focusing on the association of sex crime and GHB might be counterproductive and misleading as they turn the attention away from other substances that are often used in sexual assaults.

Effects of gamma-hydroxybutyric acid on spatial learning and memory in adolescent and adult female rats

gamma-hydroxybutyric acid (GHB) has been reported to disrupt spatial learning and memory in adolescent male rats. The present study was undertaken to determine the effects of GHB on the acquisition of spatial memory in adolescent female rats, and to investigate age specificity of the behavioral impairments. Adolescent female rats were subjected to repeated GHB or saline administrations, and tested in the Morris water maze. Compared to age-matched saline controls, adolescent GHB-treated rats took significantly longer and swam greater distances to find the hidden platform. In the probe trial, GHB-treated adolescent rats spent less time in the target quadrant than saline-treated controls. There was no difference in either the swim speed or in the visual task performance between GHB-treated and saline-treated rats. To test for ontogenic specificity of the behavioral responses, adult female rats were treated with GHB and tested behaviorally in two separate experiments using a 6-day learning protocol (Experiment 1) and a 16-day learning protocol (Experiment 2). In the 6-day spatial learning and memory task, adult saline-treated rats failed to learn the task, and GHB did not alter the latency to find the platform, or performance in the probe trial. In the second behavioral protocol, a modified version of the memory task was used to test adult animals. The number of test days was increased from 6days to 16days. Adult saline-treated females learned the task in the 16-days protocol. But unlike adolescent female rat, GHB in adult rats had minimal effects on reference memory even when they had learned the spatial memory task. Performances in the probe trial by adult GHB-treated rats and saline controls were similar. Together, these data suggest that GHB impairs spatial learning specifically in adolescent female rats.

Behavioral analyses of GHB: receptor mechanisms

GHB is used therapeutically and recreationally, although the precise mechanism of action responsible for its different behavioral effects is not entirely clear. The purpose of this review is to summarize how behavioral procedures, especially drug discrimination procedures, have been used to study the mechanism of action of GHB. More specifically, we will review several different drug discrimination procedures and discuss how they have been used to qualitatively and quantitatively study different components of the complex mechanism of action of GHB. A growing number of studies have provided evidence that the behavioral effects of GHB are mediated predominantly by GABAB receptors. However, there is also evidence that the mechanisms mediating the effects of GHB and the prototypical GABAB receptor agonist baclofen are not identical, and that other mechanisms such as GHB receptors and subtypes of GABAA and GABAB receptors might contribute to the effects of GHB. These findings are consistent with the different behavioral profile, abuse liability, and therapeutic indications of GHB and baclofen. A better understanding of the similarities and differences between GHB and baclofen, as well as the pharmacological mechanisms of action underlying the recreational and therapeutic effects of GHB, could lead to more effective medications with fewer adverse effects.

Cataleptic effects of gamma-hydroxybutyrate (GHB) and baclofen in mice: mediation by GABA(B) receptors, but differential enhancement by N-methyl-d-aspartate (NMDA) receptor antagonists

RATIONALE

Gamma-hydroxybutyrate (GHB) is a gamma-aminobutyric acid (GABA) analog that is used to treat narcolepsy but that is also abused. GHB has many actions in common with the GABA(B) receptor agonist baclofen, but their underlying GABA(B) receptor mechanisms may be different.

OBJECTIVE

The aim of this study is to further investigate a possible differential role of glutamate in GABA(B) receptor-mediated effects of GHB and baclofen.

MATERIALS AND METHODS

The experiments examined the effects of non-competitive antagonists at the N-methyl-d-aspartate (NMDA) subtype of glutamate receptors on GHB-induced catalepsy and compared these effects with those on baclofen-induced catalepsy.

RESULTS

In C57BL/6J mice, ketamine, phencyclidine (PCP), and dizocilpine (MK-801) all enhanced GHB-induced catalepsy. They did so with a potency order (i.e., MK-801 > PCP > ketamine) consistent with their relative potencies as NMDA antagonists but not as inhibitors of dopamine or organic cation transporters. Ketamine, PCP, and MK-801 enhanced catalepsy along inverted U-shaped dose-response curves likely because higher doses affected motor coordination, which limited their catalepsy-enhancing effects. Doses that were maximally effective to enhance GHB-induced catalepsy did not affect the cataleptic effects of baclofen.

CONCLUSIONS

The finding that NMDA receptor antagonists enhance the cataleptic effects of GHB but not those of baclofen is further evidence that the GABA(B) receptor mechanisms mediating the effects of GHB and GABA(B) agonists are not identical. Differential interactions of glutamate with the GABA(B) receptor mechanisms mediating the effects of GHB and baclofen may explain why GHB is effective for treating narcolepsy and is abused, whereas baclofen is not.

Gamma-hydroxybutyric acid (GHB) measurement by GC-MS in blood, urine and gastric contents, following an acute intoxication in Belgium

Gamma-hydroxybutyrate (GHB, sodium oxybate) is a compound related to neuromodulator gamma-aminobutyric acid (GABA), emerging as a recreational drug of abuse and as a rape drug. GHB-related emergencies have dramatically increased in the 1990s, but a decrease is observed since 2000. We describe the case of an acute GHB intoxication in a 28-year-old male who fell unconscious after ingestion of a mouthful of an unknown beverage, and required medical support for 2 days. A cocaine abuse was also detected by preliminary toxicological screening, but the clinical presentation was not typical of cocaine intoxication. A simple liquid-liquid extraction was used for quantitation of GHB, followed by disilyl-derivatization and analysis in selective ion monitoring (SIM) mode by gas chromatography-mass spectrometry (GC-MS), using GHB-d6 as internal standard. High concentrations of GHB were detected in urine (3020 mg/L) and gastric contents (71487 mg/L) at admission. After a 6-hours delay, GHB was still present in urine at 2324 mg/L and in blood at 43 mg/L. The clinical symptoms of cocaine intoxication were diminished by GHB consumption, and the cerebral scan was modified. Attention must thus be paid to acute intoxications with surprising clinical symptoms, and GHB has probably to be added to the preliminary toxicological screening. Data available regarding GHB are briefly reviewed, and our results are compared with previously published reports of non-fatal GHB intoxication.

Use, function, and subjective experiences of gamma-hydroxybutyrate (GHB)

Self-reported use of gamma-hydroxybutyrate (GHB) among clubbers has increased over the last decade, and is often reported in the scientific literature in association with negative events such as amnesia, overdose, and use in drug facilitated sexual assault. However, there has been relatively little work investigating the phenomenology of GHB intoxication, and the reasons underlying use. In this study, 189 individuals reporting at least one lifetime use of GHB completed an online questionnaire recording GHB use behaviours, GHB use function, and subjective GHB effects. The most frequently reported primary GHB use functions were for recreation (but not in nightclubs) (18.3%); to enhance sex (18.3%); to be sociable (13.1%); and to explore altered states of consciousness (13.1%). GHB was more commonly used within the home (67%) compared to nightlife environments (26.1%) such as clubs, although this differed on the basis of respondent's sexuality. Principle components analysis of GHB user responses to the subjective questionnaire revealed six components: general intoxication effects, positive intoxication effects, negative intoxication effects, negative physiological effects, positive sexual effects and negative sexual effects. Component scores predicted function of use.

Cataleptic effects of gamma-hydroxybutyrate (GHB), its precursor gamma-butyrolactone (GBL), and GABAB receptor agonists in mice: differential antagonism by the GABAB receptor antagonist CGP35348

RATIONALE

Gamma-hydroxybutyrate (GHB) is used to treat narcolepsy but is also abused. GHB has many actions in common with the GABA(B) receptor agonist baclofen.

OBJECTIVE

To further study the role of GABA(B) receptors in the effects of GHB.

MATERIALS AND METHODS

The experiments examined the ability of the GABA(B) receptor antagonist CGP35348 to attenuate GHB-induced catalepsy in comparison with its ability to attenuate the cataleptic effects of GABA(B) receptor agonists.

RESULTS

In C57BL/6J mice, GHB, the GHB precursor gamma-butyrolactone (GBL), and the GABA(B) receptor agonists baclofen and SKF97541 all produced catalepsy but differed in potency (i.e., SKF97541>baclofen>GBL>GHB) and in onset of action. The cataleptic effects of drug combinations were assessed at the time of peak effect of each compound, i.e., 60 min after CGP35348 and 60, 30, 30, and 15 min after baclofen, SKF97541, GHB, and GBL, respectively. At 100 mg/kg, CGP35348 shifted the dose-response curves of baclofen and SKF97541 to the right but not those of GHB and GBL; at 320 mg/kg, CGP35348 shifted the curves of all four compounds to the right.

CONCLUSIONS

The finding that CGP35348 was about threefold less potent to antagonize GHB and GBL than baclofen and SKF97541 is further evidence that the mechanisms mediating the effects of GHB and GABA(B) agonists are not identical. Differential involvement of GABA(B) receptor subtypes, or differential interactions with GABA(B) receptors, may possibly explain why GHB is effective for treating narcolepsy and is abused whereas baclofen is not.

5-Year trends in use of hallucinogens and other adjunct drugs among UK dance drug users

AIMS

To describe and assess trends in the use of hallucinogens and other adjunct drugs over a 5-year period.

DESIGN

Repeated-measures cross-sectional survey.

SETTING AND PARTICIPANTS

Annual magazine-based survey targeting people who use drugs in dance contexts.

MEASUREMENTS

Lifetime use prevalence (ever used); age of first use; current use prevalence (any use within the last month), and extent of use within the last month (number of days used) for LSD, psilocybin, ketamine, GHB and nitrates.

FINDINGS

Prevalence increases for psilocybin, ketamine, GHB and nitrates use have been detected, with a sharp recent rise in current psilocybin use in 2002-2003 contrasting with more gradual and comprehensive evidence of increased ketamine use throughout the period 1999-2003. The declining prevalence of LSD use in general population surveys is replicated in this sentinel population study.

CONCLUSIONS

The rise in prevalence of hallucinogen and other adjunct drugs identified among dance drug users may be mirrored by wider prevalence increases among young people with a consequent need to study these trends carefully and to develop effective interventions, where required.

Discriminative stimulus effects of GHB and GABAB agonists are differentially attenuated by CGP35348

The aim of this study was to examine the possible heterogeneity of mechanisms that contribute to the discriminative stimulus and rate-decreasing effects of gamma-hydroxybutyrate (GHB). Dose effect curves were determined for GHB and two GABA(B) receptor agonists (baclofen and SKF97541) alone and together with the selective GABA(B) receptor antagonist CGP35348 in rats discriminating GHB. In a second study, GHB and SKF97541 dose effect curves were determined alone and together with baclofen. CGP35348 attenuated the discriminative stimulus and rate-decreasing effects of SKF97541 and baclofen to a greater extent than those of GHB. In the second study, baclofen enhanced the discriminative stimulus and rate-decreasing effects of GHB and SKF97541; however, the GHB dose effect curve was not shifted in a parallel manner. Taken together, these data suggest that multiple mechanisms, possibly including GHB receptors and GABA(B) receptor subtypes, are involved in the discriminative stimulus and rate-decreasing effects of GHB.