Gamma hydroxy butyrate abuse and dependency

[Withdrawal syndrome after abuse of GHB (Gamma-Hydroxybutyrate) and its physiological precursors - its relevance for child and adolescent psychiatrists]

BACKGROUND

The chronic abuse of Gamma-Hydroxybutyrate (GHB) as a designer drug as well as it's physiological precursors Gamma-Butyrolactone (GBL) and 1,4-Butandiole (1,4-BD) confronts child and adolescent psychiatrists with new challenges. The acute withdrawal of GHB with its cardiovascular and delirant symptoms is of particular importance for child and adolescent psychiatrists.

METHODS

In the present paper theoretical and biological aspects of acute GHB-/GBL-/1,4-BD-withdrawal syndrome are presented, and selected cases are discussed as regards potential treatment.

RESULTS

High dose treatment with benzodiazepines was successful in some cases of acute GHB-/GBL-/1,4-BD-withdrawal syndrome. Complications were severe dystonia under neuroleptic treatment, and also side-effects of treatment with benzodiazepines. Further problems were vegetative symptoms, electrocardiographic changes, rhabdomyolysis, acute renal failure, and death.

CONCLUSION

Acute GHB-withdrawal syndrome is a life-threatening condition which requires immediate intensive care treatment along with continuous monitoring of vital parameters. As acute GHB-withdrawal syndrome can present with symptoms close to psychotic episodes or acute alcohol withdrawal this condition is relevant for child and adolescent psychiatrists.

A review of tolerability and abuse liability of gamma-hydroxybutyric acid for insomnia in patients with schizophrenia

BACKGROUND

Approved therapeutic uses for gamma-hydroxybutyric acid (GHB) (or sodium oxybate), a gamma-aminobutyric acid type B and GHB receptor agonist, include narcolepsy in the United States and Europe and alcohol abuse treatment in Italy. Possible efficacy of GHB in schizophrenia has also been proposed. A tolerability concern regarding use of GHB is its abuse potential. Given the high comorbidity of substance disorders and schizophrenia, a systematic assessment of the published literature is crucial.

OBJECTIVE

The aim of this review was to assess the tolerability and abuse liability of GHB in the context of future clinical studies as a potential treatment for insomnia in patients with schizophrenia.

METHODS

A literature search in English (inception through April 2009, inclusive) was conducted of MEDLINE, EMBASE, and PsycINFO using the search term GHB. All articles whose abstracts mentioned human use of GHB were read in their entirety. The reference sections of identified articles were reviewed for publications that might have been missed by the initial search.

RESULTS

GHB is abused by a small percentage of people (<1%) as a "club drug" and is commonly associated with enhanced sexual experiences (65%), euphoria (41%), somnolence (71%), and confusion (24%), according to a recent study. A review of all available emergency room case series suggests that while GHB can be associated with serious coma necessitating intubation, the number of reported fatal cases associated with GHB appears limited. Clarity on the lethality of GHB is complicated by instability of GHB in postmortem samples and frequent concomitant ingestions. Furthermore, formal abuse liability studies do not support high abuse propensity for GHB, mainly because oversedation and dizziness may lead most individuals to find GHB unpleasant at high doses. As supported by 2 large studies, there is limited evidence to suggest widespread use as an agent in sexual assault. Years of clinical use in narcolepsy do not support the development of tolerance or withdrawal in those subjects without substance dependence.

CONCLUSIONS

Tolerability and abuse liability issues, while a concern with GHB given its abuse potential, do not preclude further study of the potential use for insomnia in nondually diagnosed schizophrenia. Full cognizance must be taken of risk/benefit tradeoffs, and to the development of improved formulations with decreased abuse liability.

Behavioral effects of gamma-hydroxybutyrate, its precursor gamma-butyrolactone, and GABA(B) receptor agonists: time course and differential antagonism by the GABA(B) receptor antagonist 3-aminopropyl(diethoxymethyl)phosphinic acid (CGP35348)

Gamma-hydroxybutyrate (GHB) is used therapeutically and recreationally. The mechanism by which GHB produces its therapeutic and recreational effects is not entirely clear, although GABA(B) receptors seem to play an important role. This role could be complex, because there are indications that different GABA(B) receptor mechanisms mediate the effects of GHB and the prototypical GABA(B) receptor agonist baclofen. To further explore possible differences in underlying GABA(B) receptor mechanisms, the present study examined the effects of GHB and baclofen on operant responding and their antagonism by the GABA(B) receptor antagonist 3-aminopropyl(diethoxymethyl)phosphinic acid (CGP35348). Pigeons were trained to peck a key for access to food during response periods that started at different times after the beginning of the session. In these pigeons, GHB, its precursor gamma-butyrolactone (GBL), and the GABA(B) receptor agonists baclofen and 3-aminopropyl(methyl)phosphinic acid hydrochloride (SKF97541) decreased the rate of responding in a dose- and time-dependent manner. CGP35348 shifted the dose-response curve of each agonist to the right, but the magnitude of the shift differed among the agonists. Schild analysis yielded a pA(2) value of CGP35348 to antagonize GHB and GBL [i.e., 3.9 (3.7-4.2)] that was different (P = 0.0011) from the pA(2) value to antagonize baclofen and SKF97541 [i.e., 4.5 (4.4-4.7)]. This finding is further evidence that the GABA(B) receptor mechanisms mediating the effects of GHB and prototypical GABA(B) receptor agonists are not identical. A better understanding of the similarities and differences between these mechanisms, and their involvement in the therapeutic effects of GHB and baclofen, could lead to more effective medications with fewer adverse effects.

Gamma-hydroxybutyrate withdrawal syndrome: dangerous but not well-known

Gamma-hydroxybutyrate (GHB) is an endogenous inhibitory neurotransmitter and anesthetic agent that is being abused as a 'club drug.' Withdrawal symptoms after cessation of GHB use are common and depend on the intensity of use. However, GHB withdrawal syndrome and delirium are unfamiliar to most psychiatrists, probably due to the fact that neither textbooks nor guidelines cover the subject. The GHB withdrawal syndrome may have a fulminant course that progresses to delirium. In those severe cases, admission to a general hospital and involvement of a psychiatrist become necessary. We present two cases of severe GHB withdrawal delirium, provide an overview of the literature and conclude with treatment recommendations.

Should ethanol be scheduled as a drug of high risk to public health?

Six criteria described in the New Zealand Misuse of Drugs Act and used by the Expert Advisory Committee on Drugs (EACD) for determining the risk of a drug to public health were examined in relation to ethanol, using gamma-hydroxybutyric acid (GHB) as a comparator drug. GHB is an ideal candidate for use as a comparator because it is a sedative substance very similar to ethanol and has been previously investigated by the EACD using these six criteria. GHB was subsequently classified as a Class B1 drug under the Misuse of Drugs Act, that is, as a prohibited drug of high risk to public health. The dangerousness level of ethanol was found to be at least similar to that of GHB in this analysis. This highlights a major discrepancy in public policy.

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.

Area-level socioeconomic status in relation to outcomes in gamma-hydroxybutyrate intoxication

BACKGROUND

Area-level socioeconomic status (SES) may play an important role in drug abuse patterns, including related health outcomes. This may be particularly relevant for gamma-hydroxybutyrate (GHB), which is prototypical of "party" drug abuse.

METHODS

We retrospectively reviewed GHB-related cases reported to the California Poison Control System (CPCS; January 1, 1999 through June 30, 2007). We limited analysis to CPCS calls containing a residential zip code (ZC). The CPCS data were extracted for key case characteristics, including the residential ZC. We linked cases to corresponding 2000 U.S. Census data for area-level measures of SES and demographics. We used multiple logistic regression analysis to test the associations between area-level SES and GHB case severity, taking into account area-level demographics and individual-level GHB high-risk behaviors.

RESULTS

We analyzed 210 cases. Taking into account area-level demographics (age and racial mix; urbanicity) and GHB-related high-risk behaviors (use of GHB congeners; GHB-dependence; co-ingestion of other agents), we associated higher area-level SES with greater GHB case severity. There was 40% increased likelihood of major GHB adverse health outcomes for every $100,000 incremental increase in median home values (OR 1.41; 95% CI 1.1-1.8). For median annual household income (per $10,000), the association was similar (OR 1.39; 95% CI 1.0-1.9).

CONCLUSION

Higher area-level SES is associated with greater GHB-related case severity. This study may serve as a model using a geographic information system (GIS) approach to study the population-based correlates of drugs of abuse reported through poison control surveillance.

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.

Systematic assessment of gamma hydroxybutyrate (GHB) effects during and after acute intoxication

We adapted and tested a previously published questionnaire battery eliciting sensory and cognitive symptoms during (acute) and immediately after (post-acute) GHB intoxication. Studying 125 GHB users, we assessed the instrument's internal consistency using Cronbach's alpha (CA) and responsiveness to change comparing acute and post-acute symptoms. The final 14-item battery demonstrated good internal consistency (CA >or= 0.85, both acute and post-acute). The median symptom score (possible range 0-64) was 30 (acute) and 6 (post-acute; difference p < 0.001). This modified substance-specific symptom battery, which is easily administered, demonstrated excellent performance characteristics. It can be used to study GHB and, potentially, related drugs of abuse.

Drug abuse and dependency during pregnancy: anaesthetic issues

Drug abuse is a significant social problem that can lead to serious obstetric complications, some of which may be confused with pregnancy-related disease states. Substance abuse poses a number of challenges with respect to the management of pain and the conduct of anaesthesia in the peripartum period. This review was based on information from a literature search of epidemiological, research and review papers on substance abuse during pregnancy, obtained for the purpose of preparing a background paper for the Ministerial Council on Drug Strategy, Commonwealth Government of Australia. Given that almost 80% of substance-abusing parturients require anaesthetic services in the perinatal period, early antenatal referral for anaesthetic review is recommended. To optimise the care of these vulnerable patients, obstetricians, general practitioners and midwives should attempt to identify substance-abusing parturients and refer them to an anaesthetist. A careful anaesthetic evaluation with non-judgemental questioning is essential, with management tailored to individual patient needs and the urgency of obstetric intervention for vaginal delivery or caesarean section. Opioid-dependent women, in particular, benefit from antenatal pain management planning. Patients recovering from drug addiction should also have a well-documented analgesic strategy. A multidisciplinary approach will involve obstetricians, anaesthetists and staff of the Drug and Alcohol Service. In acute admissions of women by whom antenatal care was not accessed, a high index of suspicion for illicit drug use should arise. Because illicit substance use is so prevalent, if untoward reactions occur during an otherwise uneventful anaesthetic, the possibility of drug abuse should be considered.

Relative abuse liability of gamma-hydroxybutyric acid, flunitrazepam, and ethanol in club drug users

OBJECTIVES

Despite the increasing concern about gamma-hydroxybutyric acid (GHB) toxicity, there are few studies examining the clinical pharmacology of GHB and its abuse potential. To evaluate GHB-induced subjective and physiological effects, its relative abuse liability and its impact on psychomotor performance in club drug users.

MATERIALS AND METHODS

Twelve healthy male recreational users of GHB participated in 5 experimental sessions in the framework of a clinical trial. The study was randomized, double-blind, double-dummy, and crossover. Drug conditions were a single oral dose of GHB (40 or 60 mg/kg), ethanol (0.7 g/kg), flunitrazepam (1.25 mg), and placebo. Study variables included vital signs (blood pressure, heart rate, oral temperature, pupil diameter), psychomotor performance (digit symbol substitution test, balance, Maddox-Wing), subjective effects (a set of 13 visual analogue scales, Addiction Research Center Inventory-49 items, and Evaluation of the Subjective Effects of Substances with Potential of Abuse questionnaires), and pharmacokinetics.

RESULTS

All active conditions induced positive effects related to their abuse potential. The administration of GHB produced euphoria and pleasurable effects with slightly higher ratings than those observed for flunitrazepam and ethanol. Gamma-hydroxybutyric acid induced a biphasic time profile with an initial stimulant-like effect related to the simultaneous rise of plasma concentrations and a latter sedative effect not related to GHB kinetics. Gamma-hydroxybutyric acid increased blood pressure and pupil diameter. Ethanol induced its prototypical effects, and flunitrazepam produced marked sedation. Gamma-hydroxybutyric acid and flunitrazepam impaired psychomotor performance, digit symbol substitution test, and balance task, whereas ethanol, at the dose tested, induced only mild effects exclusively affecting the balance task.

CONCLUSIONS

Our results suggest a high abuse liability of GHB and flunitrazepam in club drug users.

Adolescents' sexual scripts: schematic representations of consensual and nonconsensual heterosexual interactions

The characteristic features of adolescents' sexual scripts were explored in 400 tenth and eleventh graders from Berlin, Germany. Participants rated the prototypical elements of three scripts for heterosexual interactions: (1) the prototypical script for the first consensual sexual intercourse with a new partner as pertaining to adolescents in general (general script); (2) the prototypical script for the first consensual sexual intercourse with a new partner as pertaining to themselves personally (individual script); and (3) the script for a nonconsensual sexual intercourse (rape script). Compared with the general script for the age group as a whole, the individual script contained fewer risk elements related to sexual aggression and portrayed more positive consequences of the sexual interaction. Few gender differences were found, and coital experience did not affect sexual scripts. The rape script was found to be close to the "real rape stereotype." The findings are discussed with respect to the role of sexual scripts as guidelines for behavior, particularly in terms of their significance for the prediction of sexual aggression.

An interactive lesson in acid/base and pro-drug chemistry using sodium gamma-hydroxybutyrate and commercial test coasters

OBJECTIVE

To develop a classroom activity that applied pertinent pharmaceutical concepts to examine the use and limitations of a commercially available test drink coaster in detecting the presence of a date-rape drug, sodium gamma-hydroxybutyrate (NaGHB), in beverages.

DESIGN

An activity exercise involving a combination of self-study, hands on participation, and classroom discussion was developed. Topics incorporated into the activity were drug-assisted rape, the concepts of false positives and negatives, and prodrug and pH chemistry.

ASSESSMENT

Based on questionnaires completed by the students, the intended concepts were reinforced and students demonstrated an increased awareness of the potential shortcomings of the commercial test devices. The activity was well received by the majority of students.

CONCLUSION

The developed activity stimulated student awareness and interest in several principles relevant in pharmaceutical education, including drug-assisted rape, consumer-based drug testing of NaGHB, and the chemical basis for its limitations. The activity requires no special equipment other than the drink coasters and can be easily completed in one 2-hour classroom session.

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.

Development of a rational scale to assess the harm of drugs of potential misuse

Drug misuse and abuse are major health problems. Harmful drugs are regulated according to classification systems that purport to relate to the harms and risks of each drug. However, the methodology and processes underlying classification systems are generally neither specified nor transparent, which reduces confidence in their accuracy and undermines health education messages. We developed and explored the feasibility of the use of a nine-category matrix of harm, with an expert delphic procedure, to assess the harms of a range of illicit drugs in an evidence-based fashion. We also included five legal drugs of misuse (alcohol, khat, solvents, alkyl nitrites, and tobacco) and one that has since been classified (ketamine) for reference. The process proved practicable, and yielded roughly similar scores and rankings of drug harm when used by two separate groups of experts. The ranking of drugs produced by our assessment of harm differed from those used by current regulatory systems. Our methodology offers a systematic framework and process that could be used by national and international regulatory bodies to assess the harm of current and future drugs of abuse.

Relative abuse liability of GHB in humans: A comparison of psychomotor, subjective, and cognitive effects of supratherapeutic doses of triazolam, pentobarbital, and GHB

Although preclinical studies suggest that GHB has low likelihood for abuse, case reports indicate that GHB is abused. This study evaluated the relative abuse liability of GHB in 14 volunteers with histories of drug abuse. Psychomotor, subjective, and cognitive effects of a broad range of GHB doses (2-18 g/70 kg), up to a dose that produced severe behavioral impairment in each participant, were compared to placebo and two abused sedative/hypnotic drugs, triazolam (0.5 and 1 mg/70 kg) and pentobarbital (200 and 400 mg/70 kg), under double-blind, double-dummy conditions at a residential research facility. In general, GHB produced effects similar to triazolam and pentobarbital, although GHB was not identified as a benzodiazepine or barbiturate by participants that correctly identified triazolam and pentobarbital as such. On most measures of likelihood of abuse (eg ratings of liking, reinforcing effects), effects of pentobarbital were significantly greater than those of triazolam, with GHB being intermediate. GHB produced significantly greater negative subjective effects, including nausea, than the other drugs. Memory impairment after GHB was less than that after triazolam and pentobarbital. Within participants, the dose-effect function for sedation was steeper for GHB than for triazolam and pentobarbital. Also, at higher doses, GHB was associated with greater sedation and more variability across participants in sedation. Taken together, these data suggest that the profile of effects of GHB only partially overlaps with that of triazolam and pentobarbital. Although the likelihood for GHB to be abused is intermediate to triazolam and pentobarbital, the possibility of accidental overdose (ie greater sedation than intended) with GHB appears to be greater.

-Hydroxybutyrate (GHB) in Humans: Pharmacodynamics and Pharmacokinetics

Despite gamma-hydroxybutyrate (GHB) therapeutic uses and the increasing concern about its toxicity, few studies have addressed GHB dose-related effects under controlled administration and their relationship with its pharmacokinetics. The study design was double-blind, randomized, crossover, and controlled. As a pilot pharmacology phase I study, increasing doses of GHB were given. Single oral sodium GHB doses (40, 50, 60, and 72 mg/kg) were administered to eight volunteers. Plasma and urine were analyzed for GHB by gas chromatography-mass spectrometry. Physiological effects, psychomotor performance, and subjective effects were examined simultaneously. GHB produced dose-related changes in subjective effects as measured by questionnaires and VAS. GHB showed a mixed stimulant-sedative pattern, with initially increased scores in subjective feeling of euphoria, high, and liking followed by mild-moderate symptoms of sedation with impairment of performance and balance. Mean peak GHB plasma concentrations were 79.1, 83.1, 113.5, and 130.1 mug/L for 40, 50, 60, and 72 mg/kg, respectively. GHB-mediated physiological and subjective effects were dose dependent and related to GHB plasma concentrations. GHB urinary excretion was mainly related to administered doses. GHB-mediated subjective and physiological effects seem dose dependent and related to GHB plasma concentrations. Results suggest a high abuse liability of GHB in the range of dose usually consumed.

Discriminative stimulus effects of GHB and GABA(B) 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.