Patterns of benzodiazepine abuse and dependence

The Effect of Methylphenidate on Reed Scaling in Benzodiazepine Poisoning: A Prospective Trial

BACKGROUND

Benzodiazepine is one of the most important causes of substance abuse and intoxication throughout the world and Iran.

OBJECTIVE

The aim of our study is to determine the role of stimulants in reversing CNS level in acute Benzodiazepine poisoning patients who were hospitalized at referral poison center.

METHOD

This was a randomized double-blind placebo-controlled trial study on 32 cases with pure acute Benzodiazepine poisoning from March 2016 to February 2017. Diagnosis of pure acute poisoning was based on history, and laboratory confirmation. We gathered the demographics, clinical data, laboratory data, hospitalization and outcome. Participants were randomized into two groups: Methylphenidate Group (MPH) and Placebo Group (PBO).

RESULTS

The randomized sample consisted of 32 participants who were predominately female (83%). The majority of the PBO group and the MPH group reported improvement in their consciousness with a significant difference between the two groups (p = .005). Paired sample t-test analyses on Reed Scale data revealed an increase in the probability of improvement during the trial for the MPH group compared to the PBO group. Furthermore, the HCo3 (bicarbonate) level has a significant p-value with respect to age groups (p = .02). None of our cases required either the ICU facility or intubation.

CONCLUSION

Our study provided the MPH superiority over PBO in reversing CNS symptoms in loss of consciousness in acute BZD poisoned patients. Thus, this trial provides concrete evidence that improvement in consciousness levels (Reed Scale rated) among those patients receiving MPH was associated with a methylphenidate use.

Valium without dependence? Individual GABAA receptor subtype contribution toward benzodiazepine addiction, tolerance, and therapeutic effects

Benzodiazepines are one of the most prescribed medications as first-line treatment of anxiety, insomnia, and epilepsy around the world. Over the past two decades, advances in the neuropharmacological understanding of gamma aminobutyric acid (GABA)_A receptors revealed distinct contributions from each subtype and produced effects. Recent findings have highlighted the importance of α₁ containing GABA_A receptors in the mechanisms of addiction and tolerance in benzodiazepine treatments. This has shown promise in the development of tranquilizers with minimal side effects such as cognitive impairment, dependence, and tolerance. A valium-like drug without its side effects, as repeatedly demonstrated in animals, is achievable.

Guidelines of the Brazilian Association of Studies on Alcohol and Other Drugs (ABEAD) for diagnosis and treatment of psychiatric comorbidity with alcohol and other substance and dependence

In recent years, several studies have been focused on the comorbidity of psychiatric disorders with alcohol and other substance dependence. In this context, the Brazilian Association of Studies on Alcohol and Other Drugs initiated a project to establish Brazilian Guidelines. The aim of this study was to review diagnostic and therapeutic criteria for the most prevalent psychiatric comorbidities. Randomized clinical trials, epidemiological studies, animal testing and other forms of research are reviewed herein. The main psychiatric comorbidities are investigated and data published in the literature are reviewed, based on guidelines adopted by other countries. Epidemiological aspects, diagnostic criteria, integrated treatment and the organization of specialized service, as well as details regarding psychotherapy and pharmacological treatment are discussed. The guidelines of the Brazilian Association of Studies on Alcohol and Other Drugs reinforce the importance of adequate diagnosis and treatment regarding alcoholic and drug dependent patients suffering of comorbid psychiatric disorders.

Microglia in the dorsal raphe nucleus plays a potential role in both suicide facilitation and prevention in affective disorders

An involvement of the central serotonergic system has constantly been reported in the pathogenesis of suicide. The dorsal raphe nucleus (DRN) is the main source of serotonergic innervation of forebrain limbic structures disturbed in suicidal behaviour, in which an abnormal microglia reaction seems to play a role. In our present study, the density of microglia immunostained for the HLA-DR antigen was evaluated in the DRN. These analyses were carried out on paraffin-embedded brains from 24 suicidal and 21 non-suicidal patients; among them, 27 depressed (15 major depressive disorder and 12 bipolar disorder) and 18 schizophrenia (9 residual and 9 paranoid) patients and 22 matched controls without mental disorders. Only the non-suicidal depressed subgroup revealed significantly lower microglial reaction, i.e., a decreased density of HLA-DR positive microglia versus both depressed suicide victims and controls. The effect was not related to antidepressant or antipsychotic medication, as the former correlated positively with microglial density in non-suicidal depressed patients, and the latter had no effect. Moreover, the comparison of these results with previously published data from our workgroup in the same cohort (Krzyżanowska et al. in Psychiatry Res 241:43-46, 4) suggested a positive impact of microglia on ribosomal DNA transcription in DRN neurons in the non-suicidal depressed subgroup, but not in depressed suicidal cases. Therefore, the interaction between microglia and neurons in the DRN may be potentially involved in opposite ways regarding suicide facilitation and prevention in the tested subgroups of depressed patients.

Non-medical use of olanzapine by people on methadone treatment

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

Benzodiazepine use, misuse, and abuse: A review

Benzodiazepine (BZD) abuse has reached epidemic levels and results in poor outcomes, particularly when combined with concomitant central nervous system depressants. BZDs are abused most commonly in combination with opioids and alcohol. Emergency department visits and related deaths have soared in recent years. In the absence of other medications or illicit substances, BZDs are rarely the sole cause of death. Prescription drug abuse has received more attention in recent years, yet much remains unknown about BZD abuse. BZDs have low abuse potential in most of the general population. A subset is at elevated risk of abuse, especially those with a history of a substance use disorder. Education, prevention, and identification are vital in reducing BZD abuse.

Prevalence and associated factors of hypnotics dependence among Japanese outpatients with psychiatric disorders

This study aimed to investigate the prevalence of the dependence for benzodiazepine or their agonist (BZDs) hypnotics, as well as factors associated with this dependence among Japanese psychiatric outpatients. One thousand and forty-three patients in the psychiatric outpatient clinic of Tokyo Medical University Hospital receiving treatment with BZDs hypnotics were analyzed. The subjects answered questionnaires including demographic variables, subjective sleep difficulty assessed by the Pittsburg Sleep Quality Index (PSQI), duration of hypnotics medication, dose of diazepam equivalent BZDs hypnotics, the presence or absence of subjective side effects due to BZDs hypnotics (dizziness, fatigue, daytime sleepiness, amnesia, and headache), and dependency assessed by the Dependency 2-A (D 2-A) score. Subjects with a D 2-A score ≥10 were considered as having BZDs hypnotics dependence, and the variables associated with the presence of dependence were examined using logistic regression analyses. Eighty-two out of the 1043 subjects (7.9%) were determined to have BZDs hypnotics dependence. Compared with the non-dependence group, the dependence group had a significantly higher proportion of positive respondents for all the side effects. Multiple logistic regression analyses showed that the dependence was significantly associated with younger age, higher total PSQI score, and higher daily dose of BZDs hypnotics. Younger age, higher total PSQI score, and higher dose may be associated with BZDs hypnotics dependence. The finding that patients with BZDs hypnotics dependence frequently suffered from subjective side effects and had greater sleep difficulty encourages the establishment of alternative treatments for patients with insomnia symptoms refractory to BZDs hypnotics treatment.

Benzodiazepines

Benzodiazepines have been in clinical use since the 1960s. Benzodiazepines act through allosteric modulation of the GABA_A receptor to enhance the activity of GABA, an inhibitory neurotransmitter, resulting in a slowing of neurotransmission and sedative and anxiolytic effects. Initially benzodiazepines were thought to have low dependence liability, though over time there has been increasing evidence of benzodiazepine dependence. Benzodiazepines are commonly used to treat anxiety and insomnia, though increasingly they are considered second line treatments for most indications. Concerns about the effects of benzodiazepines on cognition, falls and their implication in opioid related mortality have emerged. Few pharmacological treatments for benzodiazepine dependence have been shown to be effective with gradual taper the most common treatment strategy for benzodiazepine dependence.

Neural basis of benzodiazepine reward: requirement for α2 containing GABAA receptors in the nucleus accumbens

Despite long-standing concerns regarding the abuse liability of benzodiazepines, the mechanisms underlying properties of benzodiazepines that may be relevant to abuse are still poorly understood. Earlier studies showed that compounds selective for α1-containing GABAA receptors (α1GABAARs) are abused by humans and self-administered by animals, and that these receptors may underlie a preference for benzodiazepines as well as neuroplastic changes observed in the ventral tegmental area following benzodiazepine administration. There is some evidence, however, that even L-838, 417, a compound with antagonistic properties at α1GABAARs and agonistic properties at the other three benzodiazepine-sensitive GABAA receptor subtypes, is self-administered, and that the α2GABAARs may have a role in benzodiazepine-induced reward enhancement. Using a two-bottle choice drinking paradigm to evaluate midazolam preference and an intracranial self-stimulation (ICSS) paradigm to evaluate the impact of midazolam on reward enhancement, we demonstrated that mice carrying a histidine-to-arginine point mutation in the α2 subunit which renders it insensitive to benzodiazepines (α2(H101R) mice) did not prefer midazolam and did not show midazolam-induced reward enhancement in ICSS, in contrast to wild-type controls, suggesting that α2GABAARs are necessary for the reward enhancing effects and preference for oral benzodiazepines. Through a viral-mediated knockdown of α2GABAARs in the nucleus accumbens (NAc), we demonstrated that α2 in the NAc is necessary for the preference for midazolam. Findings imply that α2GABAARs in the NAc are involved in at least some reward-related properties of benzodiazepines, which might partially underlie repeated drug-taking behavior.

Benzodiazepine misuse and dependence among opiate addicts in treatment

Objective: Benzodiazepine misuse among opiate addicts is well described but few studies have reported on the occurrence and management of benzodiazepine dependence within this group. This study reports on the nature and extent of benzodiazepine dependence among a group of opiate addicts and describes the patients' treatment progress and requirement for substitute medication.

Method: Over a 12 month period routinely collected data on all admissions of opiate addicts to our inpatient treatment and research unit were searched. Specific details were then extracted for those 61 admissions who were opiate dependent and also currently misusing benzodiazepines.

Results: 26 (43%) of the 61 admissions were found to bephysically dependent on benzodiazepines. Temazepam and diazepam (respectively) were the most commonly misused preparations and 22% of those using temazepam were injecting it. Patients requiring detoxification were stabilised on doses of diazepam ranging from 20mg to 80mg daily (mean; 40mg). No correlation was found between reported use of benzodiazepines and the dose of diazepam required for stabilisation. Users found to be physically dependent on benzodiazepines more commonly reported daily use and use of two or more benzodiazepines concurrently.

Conclusions: Our findings suggest: 1) that benzodiazepine dependence occurs in opiate addicts with a frequency similar to that reported previously for other groups of benzodiazepine users; 2) that individuals using benzodiazepines on a daily basis may be more at risk of developing physical dependence; and 3) that clinically it is difficult to accurately predict requirements for substitute medication solely from patient's reported daily use prior to admission.

The "Prediction of Alcohol Withdrawal Severity Scale" (PAWSS): systematic literature review and pilot study of a new scale for the prediction of complicated alcohol withdrawal syndrome

BACKGROUND

To date, no screening tools for alcohol withdrawal syndromes (AWS) have been validated in the medically ill. Although several tools quantify the severity of AWS (e.g., Clinical Institute Withdrawal Assessment for Alcohol [CIWA]), none identify subjects at risk of AWS, thus missing the opportunity for timely prophylaxis. Moreover, there are no validated tools for the prediction of complicated (i.e., moderate to severe) AWS in the medically ill.

OBJECTIVES

Our goals were (1) to conduct a systematic review of the published literature on AWS to identify clinical factors associated with the development of AWS, (2) to use the identified factors to develop a tool for the prediction of alcohol withdrawal among patients at risk, and (3) to conduct a pilot study to assess the validity of the tool.

METHODS

For the creation of the Prediction of Alcohol Withdrawal Severity Scale (PAWSS), we conducted a systematic literature search using PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines for clinical factors associated with the development of AWS, using PubMed, PsychInfo, MEDLINE, and Cochrane Databases. Eligibility criteria included: (i) manuscripts dealing with human subjects, age 18 years or older, (ii) manuscripts directly addressing descriptions of AWS or its predisposing factors, including case reports, naturalistic case descriptions, and all types of clinical trials (e.g., randomized, single-blind, or open label studies), (iii) manuscripts describing characteristics of alcohol use disorder (AUD), and (iv) manuscripts dealing with animal data (which were considered only if they directly dealt with variables described in humans). Obtained data were used to develop the Prediction of Alcohol Withdrawal Severity Scale, in order to assist in the identification of patients at risk for complicated AWS. A pilot study was conducted to assess the new tool's psychometric qualities on patients admitted to a general inpatient medicine unit over a 2-week period, who agreed to participate in the study. Blind to PAWSS results, a separate group of researchers retrospectively examined the medical records for evidence of AWS.

RESULTS

The search produced 2802 articles describing factors potentially associated with increased risk for AWS, increased severity of withdrawal symptoms, and potential characteristics differentiating subjects with various forms of AWS. Of these, 446 articles met inclusion criteria and underwent further scrutiny, yielding a total of 233 unique articles describing factors predictive of AWS. A total of 10 items were identified as correlated with complicated AWS (i.e., withdrawal hallucinosis, withdrawal-related seizures, and delirium tremens) and used to construct the PAWSS. During the pilot study, a total of 68 subjects underwent evaluation with PAWSS. In this pilot sample the sensitivity, specificity, and positive and negative predictive values of PAWSS were 100%, using the threshold score of 4.

DISCUSSION

The results of the literature search identified 10 items which may be correlated with risk for complicated AWS. These items were assembled into a tool to assist in the identification of patients at risk: PAWSS. The results of this pilot study suggest that PAWSS may be useful in identifying risk of complicated AWS in medically ill, hospitalized individuals. PAWSS is the first validated tool for the prediction of severe AWS in the medically ill and its use may aid in the early identification of patients at risk for complicated AWS, allowing for prophylaxis against AWS before severe alcohol withdrawal syndromes develop.

Treatment or "high": benzodiazepine use in patients on injectable heroin or oral opioids

Benzodiazepine (BZD) use is widespread among opioid-maintained patients worldwide. We conducted a cross-sectional survey to investigate motives and patterns of BZD use and psychiatric comorbidity in a convenience sample of patients (n=193) maintained on oral opioid agonists or diacetylmorphine (DAM). Prolonged BZD use and high-risk behaviors like parenteral use were common. After principal component analysis, motives were divided into those related to negative affect regulation, positive affect regulation (i.e. reward-seeking) and somato-medical problems. Negative affect regulation and somato-medical motives were associated with prolonged use. Psychiatric comorbidity was associated with several self-therapeutic motives, most importantly to lose anxiety. Patients maintained on DAM were more likely to be ex-users of BZD and report high positive affect regulation. Therefore, patients maintained on different agonists may have deviating motives for BZD use, which could be of importance when addressing this issue. Treatment of psychiatric comorbidity, in particular anxiety, depressive and sleeping disorders, may be helpful in reducing BZD use, particularly in patients maintained on oral opioids.

Benzodiazepine use and misuse among patients in a methadone program

BACKGROUND

Benzodiazepines (BZD) misuse is a serious public health problem, especially among opiate-dependent patients with anxiety enrolled in methadone program because it puts patients at higher risk of life-threatening multiple drug overdoses. Both elevated anxiety and BZD misuse increase the risk for ex-addicts to relapse. However, there is no recent study to assess how serious the problem is and what factors are associated with BZD misuse. This study estimates the prevalence of BZD misuse in a methadone program, and provides information on the characteristics of BZD users compared to non-users.

METHODS

An anonymous survey was carried out at a methadone program in Baltimore, MD, and all patients were invited to participate through group meetings and fliers around the clinic on a voluntary basis. Of the 205 returned questionnaires, 194 were complete and entered into final data analysis. Those who completed the questionnaire were offered a $5 gift card as an appreciation.

RESULTS

47% of the respondents had a history of BZD use, and 39.8% used BZD without a prescription. Half of the BZD users (54%) started using BZD after entering the methadone program, and 61% of previous BZD users reported increased or resumed use after entering methadone program. Compared to the non-users, BZD users were more likely to be White, have prescribed medication for mental problems, have preexistent anxiety problems before opiate use, and had anxiety problems before entering methadone program. They reported more mental health problems in the past month, and had higher scores in anxiety state, depression and perceived stress (p < .05).

CONCLUSIONS

Important information on epidemiology of BZD misuse among methadone-maintenance patients suggests that most methadone programs do not address co-occurring anxiety problems, and methadone treatment may trigger onset or worsening of BZD misuse. Further study is needed to explore how to curb misuse and abuse of BZD in the addiction population, and provide effective treatments targeting simultaneously addiction symptoms, anxiety disorders and BZD misuse.

Orexin receptors: pharmacology and therapeutic opportunities

Orexin-A and -B (also known as hypocretin-1 and -2) are neuropeptides produced in the lateral hypothalamus that promote many aspects of arousal through the OX1 and OX2 receptors. In fact, they are necessary for normal wakefulness, as loss of the orexin-producing neurons causes narcolepsy in humans and rodents. This has generated considerable interest in developing small-molecule orexin receptor antagonists as a novel therapy for the treatment of insomnia. Orexin antagonists, especially those that block OX2 or both OX1 and OX2 receptors, clearly promote sleep in animals, and clinical results are encouraging: Several compounds are in Phase III trials. As the orexin system mainly promotes arousal, these new compounds will likely improve insomnia without incurring many of the side effects encountered with current medications.

Anxiolytic and hypnotic drug misuse in Thailand: findings from a national household survey

INTRODUCTION AND AIMS

The non-medical use of prescription drugs, such as anxiolytics and hypnotics, has become a growing public health problem in Thailand. The objective of this study was to examine the patterns of non-medical use of these drugs, using data from a nationally representative sample of Thais interviewed in 2007.

DESIGN AND METHODS

A nationwide, multi-stage, household survey of 26 633 respondents aged 12-65 years living in 11 348 households throughout Thailand using a face-to-face structured interview questionnaire was carried out.

RESULTS

In 2007, 1.58% (734 288) and 1.58% (733 318) of Thais indicated that they had misused anxiolytics or hypnotics, respectively, at some time during their lives. Less than 1% had misused these drugs during the 12 months preceding the interview (426 170 or 0.92% for anxiolytics, 372 920 or 0.80% for hypnotics), fewer during the preceding 30 days (234 871 or 0.50% for anxiolytics, 225 638 or 0.48% for hypnotics).The highest prevalence of past 30 day use was in Bangkok, the lowest in Southern Thailand. More women than men, older than younger respondents, and subjects who considered they were in poor physical health or had emotional problems than those who thought otherwise used the drugs during the 30 days before the interviews.

DISCUSSION AND CONCLUSIONS

The prevalence of anxiolytic/hypnotic misuse/abuse appears to be lower than that reported from more developed countries, but a small increase in problems resulting from the use of these substances has a disproportionately large effect on the overstretched resources of a developing country.

Tolerance, sensitization and dependence to diazepam in Balb/c mice exposed to a novel open space anxiety test

Balb/c mice were exposed to an elevated platform that is extended on two opposite sides with lowered steep slopes. They were tested for 12min per session in 6 successive days. They received i.p. administration of either saline or one dose of diazepam (DZP 0.5, 1, 3mg/kg) in sessions 1-3, and saline in sessions 4 and 5. All groups of mice received a single dose of DZP (1mg/kg) in session 6. DZP produced inverted U-shaped dose-responses on the number of entries into different areas of the apparatus, with a peak in mean response at 1mg/kg whereas its effect on the duration of entries was mostly comparable between the 3 doses. It increased the number of crossings on the surface of the platform and facilitated entries onto the slopes. DZP-treated mice crossed frequently onto and spent longer time on the slopes in sessions 1-3 whereas saline-treated mice remained on the platform in sessions 1-6. Withdrawal of DZP in sessions 4-5 increased the latency of first entry and decreased the number and duration of entries onto the slopes which was reversed with the administration of 1mg/kg of DZP in the next session. This ON-OFF the drug may be due to the half-life of DZP which is very short in mice and rats ( approximately 0.88h). It also indicates that DZP-treated mice did not benefit from previous experience of entries onto the slopes which suggests a possible "state-dependent" effect. Administration of DZP after repeated exposures to the test did not facilitate entries onto the slopes but instead increased significantly the number of crossings on the surface of the platform; this increase was much higher than that observed in mice initially treated with DZP and exposed to the test. There is no evidence of habituation in saline-treated mice: the number of crossings on the platform was comparable between the first 5 sessions of the test. These results demonstrate that repeated exposures to the same anxiogenic environment resulted in avoidance responses developing tolerance and approach responses developing sensitization. They suggest that tolerance and sensitization are two opposite sides of the habituation process to the same stimulus and may account for the maintained state of anxiety.

Self-perceived motivation for benzodiazepine use and behavior related to benzodiazepine use among opiate-dependent patients

Clinical observations have shown a high prevalence of benzodiazepine use among opiate-dependent patients. Our objective was to identify if distinct patterns of behavior could be associated with three different self-perceived motivations for benzodiazepine use: (a) exclusive self-therapeutic motivation, (b) exclusive hedonic motivation, and (c) combined self-therapeutic and hedonic motivation. Data were collected through a self-administered questionnaire in 92 opiate users in treatment in France (Aquitaine). The behaviors associated with exclusive self-therapeutic motivation included the search for an anxiolytic effect, oral administration, use within the context of a medical prescription, and use without other substances. The behaviors associated with exclusive hedonic motivation were use in combination with other substances, the obtaining of benzodiazepines by the black market, and use of other routes of administration in search of a "blackout." Among patients who reported both motivations, there were distinct trends of behavior according to motivation.

Benzodiazepine use among opiate-dependent subjects in buprenorphine maintenance treatment: correlates of use, abuse and dependence

BACKGROUND

Previous studies from North America, Europe and Australia have reported high levels of benzodiazepine use among opiate-dependent patients in opiate maintenance treatment. However, to date, there are no available data on patterns of abuse and dependence on benzodiazepines according to DSM criteria among these patients.

AIMS

To describe the independent correlates of use, abuse and dependence on benzodiazepines among buprenorphine patients selected from standard treatment settings.

METHODS

Cross-sectional study in France between June 2001 and June 2004. Buprenorphine patients treated for over 3 months were recruited via physicians prescribing buprenorphine. Patients answered a self-administered questionnaire, the DSM-IV criteria for benzodiazepine abuse and dependence, the Beck Anxiety and Depression Inventories (BAI, BDI) and the Nottingham Health Profile (NHP). Main outcome was modalities of benzodiazepine use: no use vs. simple use vs. problematic use (abuse or dependence according to DSM-IV).

RESULTS

170 patients were recruited. 54% did not use benzodiazepines during the previous month, 15% were simple users and 31% were problematic users. Benzodiazepine use (all modalities) was associated with poly-use of psychotropics. Simple users of benzodiazepines were not statistically different from non-users for the other factors explored. Problematic users of benzodiazepines had higher depression and anxiety levels, correlated with quality of life impairment and precariousness. They used higher dosages of benzodiazepines than simple users.

CONCLUSIONS

Characteristics of simple benzodiazepine users were distinct from problematic users but not from non-users in this sample of buprenorphine patients. This should be taken into account in the clinical management of benzodiazepine use among buprenorphine patients.

Analysis of the chronic intake of and withdrawal from diazepam on emotional reactivity and sensory information processing in rats

It has been demonstrated that, on abrupt withdrawal, patients with chronic exposure can experience a number of symptoms indicative of a dependent state. In clinical patients, the earliest to arise and most persistent signal of withdrawal from chronic benzodiazepine (Bzp) treatment is anxiety. In laboratory animals, anxiety-like effects following abrupt interruption of chronic Bzp treatment can also be reproduced. In fact, signs that oscillate from irritability to extreme fear behaviours and seizures have been described already. As anxiety remains one of the most important symptoms of Bzp withdrawal, in this study we evaluated the anxiety levels of rats withdrawn from diazepam. Also studied were the effects on the motor performance and preattentive sensory gating process of rats under diazepam chronic treatment and upon 48-h withdrawal on three animal models of anxiety, the elevated plus-maze (EPM), ultrasonic vocalizations (USV) and startle+prepulse inhibition tests. Data obtained showed an anxiolytic- and anxiogenic-like profile of the chronic intake of and withdrawal from diazepam regimen in the EPM test, 22-KHz USV and startle reflex. Diazepam chronic effects or its withdrawal were ineffective in promoting any alteration in the prepulse inhibition (PPI). However, an increase of PPI was achieved in both sucrose and diazepam pretreated rats on 48-h withdrawal, suggesting a procedural rather than a specific effect of withdrawal on sensory gating processes. It is also possible that the prepulse can function as a conditioned stimulus to informing the delivery of an aversive event, as the auditory startling-eliciting stimulus. All these findings are indicative of a sensitization of the neural substrates of aversion in diazepam-withdrawn animals without concomitant changes on the processing of sensory information.

Up-regulation of L-type high voltage-gated calcium channel subunits by sustained exposure to 1,4- and 1,5-benzodiazepines in cerebrocortical neurons

The aim of this study is to examine how sustained exposure to two 1,4-benzodiazepines (BZDs) with different action period, diazepam and brotizolam, and a 1,5-BZD, clobazam, affects L-type high voltage-gated calcium channel (HVCC) functions and its mechanisms using primary cultures of mouse cerebral cortical neurons. The sustained exposure to these three BZDs increased [(45)Ca2+] influx, which was due to the enhanced [(45)Ca2+] entry through L-type HVCCs but not through of Cav2.1 and Cav2.2. Increase in [(3)H]diltiazem binding after the exposure to these three BZDs was due to the increase in the binding sites of [(3)H]diltiazem. Western blot analysis showed increase of Cav1.2 and Cav1.3 in association with the increased expression of alpha2/delta1 subunit. Similar changes in [(3)H]diltiazem binding and L-type HVCC subunit expression were found in the cerebral cortex from mouse with BZD physical dependence. These results indicate that BZDs examined here have the potential to increase L-type HVCC functions mediated via the enhanced expression of not only Cav1.2 and Cav1.3 but also alpha2/delta1 subunit after their sustained exposure, which may participate in the development of physical dependence by these BZDs.

Brainstem areas activated by diazepam withdrawal as measured by Fos-protein immunoreactivity in rats

In the 1970s, chronic treatment with benzodiazepines was supposed not to cause dependence. However, by the end of the decade several reports showed that the interruption of a prolonged treatment with diazepam leads to a withdrawal syndrome characterized, among other symptoms, by an exaggerated level of anxiety. In laboratory animals, signs that oscillate from irritability to extreme fear-like behaviors and convulsions have also been reported. In recent years many studies have attempted to disclose the neural substrates responsible for the benzodiazepines withdrawal. However, they have focused on telencephalic structures such as the prefrontal cortex, nucleus accumbens and amygdala. In this study, we examined the Fos immunoreactivity in brain structures known to be implicated in the neural substrates of aversion in rats under spontaneous diazepam-withdrawal. We found that the same group of structures that originally modulate the defensive responses evoked by fear stimuli, including the dorso-medial hypothalamus, the superior and inferior colliculus and the dorsal periaqueductal gray, were most labeled following diazepam withdrawal. It is suggested that an enhanced neural activation of neural substrates of fear in the midbrain tectum may underlie the aversive state elicited in diazepam-withdrawn rats.

Diretrizes da Associação Brasileira de Estudos do Álcool e outras Drogas (ABEAD) para o diagnóstico e tratamento de comorbidades psiquiátricas e dependência de álcool e outras substâncias

O diagnóstico e tratamento de comorbidade psiquiátrica e dependência de álcool e outras substâncias tem sido objeto de inúmeros estudos nos últimos anos. A Associação Brasileira de Estudos do Álcool e Outras Drogas desenvolveu o projeto Diretrizes. Este trabalho visa o desenvolvimento de critérios diagnósticos e terapêuticos atualizados para as comorbidades psiquiátricas mais prevalentes. Ensaios clínicos randomizados, estudos epidemiológicos, com animais e outros estudos são revisados. As principais comorbidades psiquiátricas são estudadas e os dados de literatura resumidos, tendo como referência diretrizes adotadas em outros países. São abordados aspectos epidemiológicos, critérios diagnósticos, tratamento integrado e organização de serviço especializado, assim como especificidades do tratamento psicoterápico e farmacológico. As Diretrizes da Associação Brasileira de Estudos do Álcool e Outras Drogas reforçam a importância da abordagem adequada do dependente químico portador de comorbidade psiquiátrica.

Correlates and consequences of chronic insomnia

Approximately one half of patients with insomnia have a primary psychiatric disorder such as a depression or anxiety. Insomnia is associated with increased risk of new or recurrent psychiatric disorders, increased daytime sleepiness with consequent cognitive impairment, poorer prognoses, reduced quality of life and high healthcare-related financial burden. Emerging data suggest that resolution of insomnia may improve psychiatric outcomes, which underscores the importance of vigorous treatment. Unfortunately, only a small percentage of patients receive such care. An ideal monotherapeutic strategy would treat both depression and insomnia. There are, however, only a handful of modern antidepressants that objectively improve sleep maintenance problems, and none do so without causing adverse next-day effects such as sedation. Thus, a significant number of patients must take adjunctive hypnotic medications, even though longer-term efficacy has not been established. New and emerging anti-insomnia agents may prove useful in the long-term treatment of chronic insomnia. Further research is needed to establish the benefits of such treatment.

A postmarketing study of relative abuse liability of hypnotic sedative drugs

AIMS

To demonstrate the utility of postmarketing studies using in-treatment drug and alcohol abusers as informants for assessing the relative abuse liability of sedative-hypnotic drugs.

DESIGN

A survey was conducted that ascertained exposure to a variety of drugs with hypnotic/sedative properties and elicited subjective evaluations indicative of abuse liability.

METHODS

Complete data were obtained from 297 admissions (78% male) to three addiction treatment sites in the United Kingdom. Subjects were asked 15 questions about 12 different drugs, including five benzodiazepines, three antidepressants, two non-benzodiazepine hypnotics and two antihistamines (plus one fictitious drug). Three of the benzodiazepines (diazepam, nitrazipam, temazepam) emerged as having substantially more abuse liability than any of the other drugs tested, as revealed by higher scores on abuse liability items (purchased on street, taken to get high, like drug, potential for addiction to drug). The antihistamines (chlorpheniramine, diphenhydramine) had lowest abuse liability profiles, while the antidepressants (amitriptyline, fluoxetine, trazadone) and non-benzodiazepine hypnotics (zolpidem, zopiclone) had similar profiles.

CONCLUSION

This pilot study suggests that postmarketing information on hypnotic drug use obtained from drug addicts entering treatment produces data consistent with other measures of abuse liability. The data suggest that the risk of misuse of newer non-benzodiazepine hypnotics may be less than that of benzodiazepine drugs, and similar to that of sedating antidepressants. The new methodology may serve to clarify or validate premarketing abuse liability data, and may help to inform the regulatory process and physician practice.

The prevalence and clinical course of sedative-hypnotic abuse and dependence in a large cohort

Relatively little is known about the prevalence and clinical characteristics of dependence on sedative-hypnotics, and almost nothing has been published regarding abuse. This report relates information on Diagnostic and Statistical Manual of the American Psychiatric Association (DSM-IIIR) sedative-hypnotic use disorders among subjects from the Collaborative Study on the Genetics of Alcoholism (COGA). A standardized interview was used to generate data on 407 men and women in Group 1 with sedative-hypnotic dependence (4.4% of the COGA sample), 34 in Group 2 with abuse (0.4%), and 3,426 comparison subjects in Group 3 with alcohol dependence in the absence of a sedative-hypnotic use disorder (36.7%). The remaining COGA subjects (48.5%) were not included as they had neither alcohol nor sedative-hypnotic dependence or abuse. Those with sedative-hypnotic abuse or dependence were more likely to be Caucasian individuals with abuse or dependence on marijuana, cocaine, amphetamines, or opioids. Subjects in Groups 1 and 2 were also more likely to have histories of independent major depressive and panic disorders, as well as substance-induced mood disorders. Those with dependence, compared to abuse, were likely to be women, reported staying intoxicated for a day or more, but noted less abuse of opioids or amphetamines, although Group 2 members also had high rates of difficulties with sedative-hypnotics. These results highlight notable rates of sedative-hypnotic dependence in the COGA families, and indicate that while sedative-hypnotic abuse does occur, and while the clinical course can involve relatively serious problems, it is less common than dependence.

Co-abuse of opiates and benzodiazepines

The objective of the study was to assess what differences exist between individuals who are dependent on opiates and benzodiazepines and compare to those who are dependent on opiates. A questionnaire was compiled and administered to patients who had been consecutively admitted to an inpatient drug treatment unit. The prevalence of benzodiazepine dependency was 54 per cent [n = 34]. Patients dependent on benzodiazepines and opiates were significantly older, had been admitted for methadone stabilisation and were more likely to have been prescribed a methadone maintenance programme prior to admission. They had used heroin longer, benzodiazepines more frequently, at larger doses for a longer duration of time and tended to use more drugs in general. They were found to be more psychologically vulnerable than those not dependent on benzodiazepines as they were significantly more likely to have described a past experience of depression and a past episode of deliberate self harm.

Benzodiazepine misuse by drug addicts

Using a high-performance liquid chromatography method, we measured seven commonly prescribed benzodiazepines (chlordiazepoxide, nitrazepam, nordiazepam, oxazepam, lorazepam, temazepam and diazepam) in 100 urine samples obtained from patients attending the Leeds Addiction Unit. All of the urines selected for investigation were positive for benzodiazepines using an EMIT (Enzyme Immunoassay) screen. Forty-four of the urines contained a range of benzodiazepines, none of which had been prescribed. Nitrazepam was detected most frequently (61 urine samples), but had not been prescribed to any of the patients in this study. Chlordiazepoxide was detected in 49 urine samples, although it had been prescribed to only five patients. Temazepam was detected in 28 urine samples. Fourteen patients providing 21 urine samples had been prescribed temazepam for treatment. However, temazepam was detected in only 14 of these samples. Multiple benzodiazepine abuse was evident from the high rate of detection of unrelated benzodiazepines.

Changes in "withdrawal symptoms" following discontinuation of low-dose diazepam

The intensity of putative benzodiazepine withdrawal symptoms was evaluated as part of a double blind placebo-controlled study of benzodiazepines and behaviour therapy in the management of agoraphobia. During the first phase of that study, some subjects were switched from low dose diazepam to placebo, and others remained on diazepam. Symptoms were evaluated in long-term benzodiazepine users (n = 30) and non-users n = 32) when they first entered the study and 4 weeks later, after both groups had been randomized to either diazepam or placebo, using eight analog rating scales measuring commonly reported withdrawal symptoms. At baseline, both users and non-users reported a substantial number of symptoms, with higher levels in the more anxious patients, but no differences between groups. After the transition to either diazepam or placebo, the users switched to placebo reported significantly higher levels of symptoms than users switched to diazepam and non-users combined. Multiple regression analysis suggested that the increase in symptoms was associated with the increase in anxiety, which was higher in the withdrawing group than the other three groups. These results raise questions concerning the extent to which withdrawal symptoms uniquely characterize benzodiazepine withdrawal. They confirm the common assumption that an increase in symptoms often accompanies withdrawal from benzodiazepines, but suggest that such symptoms are not so intense as to make withdrawal excessively difficult, at least in low-dose users.

The behavioural and neuronal effects of the chronic administration of benzodiazepine anxiolytic and hypnotic drugs

Benzodiazepine anxiolytic and hypnotic drugs are some of the most widely prescribed drugs in the Western world. Despite this fact, the mechanisms that underlie the development of tolerance to, and dependence upon, benzodiazepines are poorly understood. The aim of this review is to summarize and critically evaluate the experimental evidence relating to the chronic behavioural and neuronal effects of benzodiazepines. Behavioural studies in animals generally indicate that tolerance gradually develops to the muscle relaxant, ataxic, locomotor and anticonvulsant effects of benzodiazepines. The evidence relating to the development of tolerance to the anxiolytic effects of benzodiazepines is less clear. The literature on the possible mechanisms of benzodiazepine tolerance and dependence is large, highly complex and difficult to interpret. The effect of chronic benzodiazepine treatment varies enormously as a function of the benzodiazepine used and the treatment schedule employed. Many studies have demonstrated a down-regulation of benzodiazepine binding sites, although affinity is usually unchanged. The evidence relating to the number and affinity of GABAA binding sites is unclear. Some studies suggest that chronic benzodiazepine administration results in a reduction in the number of Cl- channels associated with the GABAA receptor complex, although it is not clear that the efficacy of the GABA binding site in operating the Cl- channel necessarily changes. There is, however, substantial evidence to support the hypothesis that chronic benzodiazepine treatment results in a reduction in the coupling between the GABAA and benzodiazepine binding sites (the "functional uncoupling hypothesis"). Although some electrophysiological studies suggest that chronic benzodiazepine treatment results in a subsensitivity to GABA, this effect seems to be highly area-specific.

Pharmacotherapy of insomnia: practice and prospects

Insomnia is a complex complaint which is often multifactorial in origin. Pharmacotherapy can only be an adjunct in the treatment of insomnia and hypnotics should be given on an intermittent basis for short periods of time. An overview is presented of the currently available hypnotics, of which benzodiazepines are still the most widely prescribed. New drugs which bind to specific receptor subtypes or which are partial benzodiazepine receptor agonists might overcome the disadvantages associated with chronic benzodiazepine use, but more long-term investigations are needed.

Long-term benzodiazepine users--a mixed bag

In this article it is argued that long-term benzodiazepine (BZD) users can be classified into four broad groups, namely medical, daytime, night-time and polydrug users. Although the groups are not exhaustive or mutually exclusive, such a classification may go some way to clarify our understanding of the complex psychological and sociological phenomena involved in long-term consumption of BZDs.

Anxiolytic drugs: dependence, addiction and abuse

The concepts of dependence, addiction and abuse comprise overlapping clinical phenomena. The earlier anxiolytic drugs, in particular the barbiturates, were prone to abuse, i.e., non-medical use, and to high-dose misuse. Their modern counterparts, the benzodiazepines, are abused in a patchy way and are sometimes taken in regularly high doses. However, the main problem is physical dependence as manifested by a withdrawal syndrome on discontinuation of the drug. The withdrawal syndrome has been carefully described and comprises physical and psychological features. In particular, perceptual symptoms such as photophobia, hyperacusis and feelings of unsteadiness may predominate. The syndrome may come on during dosage reduction but generally starts 2-10 days after cessation of the benzodiazepine, depending on its elimination half-life. About a third of long-term users suffer a recognisable syndrome even after a tapered withdrawal, its duration usually being only a few weeks. A few patients go on to a prolonged withdrawal syndrome, often characterised by muscular spasm. The treatment of the withdrawal syndrome is supportive and non-specific. A few patients started on benzodiazepine therapy escalate the dose. They tend to show the characteristic 'passive-dependent' personality features and may previously have misused other CNS depressants such as the barbiturates and alcohol. Abuse of benzodiazepines occurs in a rather varied way from country to country. Worldwide, flunitrazepam has caused concern but, in the UK, the main problem has been the intravenous use of temazepam. The molecular pharmacology of the benzodiazepine receptor has been extensively studied and is undoubtedly complex.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of concurrent diazepam treatment on the outcome of exposure therapy in agoraphobia

In a study designed to evaluate the impact of benzodiazepine use on the outcome of behaviour therapy, 91, severe, chronic agoraphobics (46 BDZ users and 45 non-users) were randomly allocated on a double-blind basis to in vivo exposure with low-dose diazepam (ED) or placebo (EP). Drug doses were adjusted on the basis of weekly psychiatric assessments over weeks 1-4. Patients had 8 x 2 hr exposure sessions (weeks 5-12) and were then withdrawn from medication (weeks 13-16). Re-assessments were completed at weeks 4, 12 and 16, and follow-up assessments at approx 20, 46 and 72 weeks. In the analysis of the results, the clinical outcome was evaluated in relation to the therapeutic regime (ED vs EP) and prior BDZ use (users vs non-users). The results showed that the ED group had greater changes in anxiety than the EP group during the drug manipulation phases (anxiety increasing during BDZ withdrawal). There were no group differences in agoraphobic symptoms and no evidence that the outcome of the behavior therapy was significantly affected by concurrent BDZ treatment. There were significant improvements in agoraphobic symptoms over the treatment period, with no evidence for relapse of treatment gains on withdrawal from BDZ, nor for differential responses over the one year follow-up. Initial differences between users and non-users were less marked than expected, although there was a trend for more drop-outs among users across both ED and EP groups.

Types of benzodiazepines abused by chemically dependent inpatients

Records of inpatients (N = 1,483) over a three-year period at an addiction treatment center were evaluated for the presence of benzodiazepine (BZ) dependence (N = 136). The preferred BZ for 43% of the subjects was diazepam, and alprazolam for 14% of subjects. Chlordiazepoxide, lorazepam, and clorazepate were each the preferred BZ for 4% of patients. Cocaine and opioid abusers were six times more likely to abuse diazepam than any other BZ. Alprazolam patients required a significantly longer period of detoxification than diazepam patients. Four percent of BZ-dependent patients (N = 6) abused BZs only and had no other substance abuse history.

Benzodiazepine abuse among female outpatients in India

The prevalence of benzodiazepine abuse was estimated among gynecological outpatients at a general hospital in New Delhi, India. Approximately 8% of respondents abuse benzodiazepines, with Diazepam being the most popular drug. Abuse was more common among younger and more educated women.

Tolerance to hexobarbital induced by short-term treatments with diazepam and tested with an EEG-threshold test in male rats

Male Mol: SPRD rats were treated with 5 or 20 mg/kg of diazepam for 4 days. The treatment was repeated at two different ages. Diazepam was either dissolved in Intralipid (KABI, Sweden) or dispersed in gummi arabicum. Tolerance induced by the treatment was tested with an EEG-threshold technique where hexobarbital was infused intravenously on day 1, 4, 7 and 14 of the abstinence. The threshold was the dose of hexobarbital needed to induce a burst suppression of 1 sec. or more (silent second). After the first diazepam treatment significant increase in the hexobarbital threshold doses were recorded in all but one of the diazepam treated groups. The pattern varied depending on dose, age and solvent. After the second treatment tolerance was seen only when diazepam had been dissolved in Intralipid. Short term treatment with diazepam can induce cross-tolerance to hexobarbital which probably is due to an increased excitation (physical dependence) in abstinence after treatment with diazepam.

Alprazolam and diazepam: addiction potential

Alprazolam and diazepam, the two most prescribed benzodiazepine anxiolytics in the United States, have potential for addictive use. The Drug Abuse Warning Network (DAWN) indicates they are the most mentioned benzodiazepines, and the National Household Survey indicates significant abuse of tranquilizers. Both drugs are rapidly absorbed and enter the brain tissue rapidly, leading to reinforcement. Alprazolam has a shorter half-life, which may lead to more withdrawal symptoms than diazepam. In experimental conditions, they are among the most reinforcing benzodiazepines. Each causes a withdrawal syndrome, but alprazolam withdrawal may be more severe and may occur after a shorter period of use. Adverse effects from their use are said to be rare, yet subtle negative consequences may be seen with some regularity. Alprazolam deserves special caution because of its relative newness, great popularity, reinforcing capabilities, relatively severe withdrawal syndrome, and reports of addiction and negative consequences of use.

History of benzodiazepine dependence

The benzodiazepines were developed in the 1950s, some introduced in the 1960s, and many more since then. Pharmacologically, they are sedative/hypnotics akin to alcohol, chloral, the barbiturates, and meprobamate. All have been widely used both within and outside the licit medical context. Usage of benzodiazepines increased dramatically during the 1960s and early 1970s; tranquilizer but not hypnotic usage has since declined. Both abuse and misuse were documented early, but the incidence was deemed low in view of the widespread prescription. Normal-dose physical dependence was first suspected in the early 1970s but it was not until the early 1980s that scientific evidence was adduced to establish its reality and frequency. Further studies have revealed the complex nature of the withdrawal syndrome. A reaction has set in against these drugs, with attempts to limit them to short-term use.

Snorting benzodiazepines

Two cases of intranasal benzodiazepine use are presented. The methods of preparation and administration of the powder and accounts of the pharmacological effects of the drugs used are described. The pattern of development and progress of the habit and its associated features are delineated. Snorting benzodiazepines appears to be more common than is currently appreciated, and the clinical complications and implications of this habit are discussed.

Chronic benzodiazepine dependence. A comparative study of abrupt withdrawal under propranolol cover versus gradual withdrawal

Thirty-one patients dependent on benzodiazepines were randomly assigned to either slow withdrawal (SW) or abrupt withdrawal under propranolol cover (PW). Of 16 patients in the SW group, 11 successfully withdrew from their drugs, while only 4 out of 15 in the PW group did so. Patients in the SW group had only mild withdrawal symptoms, while those in the PW group suffered more severe symptoms, which lasted around four weeks. In all, 81% of the whole group suffered withdrawal symptoms of some kind. Patients in both groups were significantly less anxious at the end of the study than at baseline. Younger subjects and those who were more severely anxious at the start of the trial had more difficulty in withdrawing than older and less anxious patients.

[Benzodiazepines: patterns of use, tolerance and dependence]

The authors review recent studies on benzodiazepine, the most largely used drug for insomnia and anxiety. In this paper are summarized: the development, patterns of use and abuse, mechanism of action, development of differential tolerance to its many effects, and the phenomena of withdrawal and dependence on the benzodiazepines.