Tapering clonazepam in patients with panic disorder after at least 3 years of treatment

Add-On Treatment with Passiflora incarnata L., herba, during Benzodiazepine Tapering in Patients with Depression and Anxiety: A Real-World Study

Chronic and inappropriate benzodiazepine intake represents an important health and social concern worldwide. The aim of our study was to investigate the effectiveness of P. incarnata L., herba, in reducing benzodiazepine misuse in a real-world population of depressed and anxious patients in a long-term treatment with benzodiazepines. We conducted a retrospective naturalistic study on 186 patients undergoing benzodiazepine downtitration, 93 with the addition of a dry extract of P. incarnata L., herba (Group A), and 93 without any add-on treatment (Group B). Regarding the benzodiazepine dosage variation in the two groups, a repeated measure ANOVA showed a significant effect of time (p < 0.001), group (p = 0.018), and time x group interaction (p = 0.011). We found a significantly higher rate, i.e., of 50%, reduction in Group A vs. Group B at 1 month (p < 0.001) and at 3 months (p < 0.001) and complete benzodiazepine discontinuation at 1 month (p = 0.002) and at 3 months (p = 0.016). Our findings suggest the role of P. incarnata as an effective add-on treatment during benzodiazepine tapering. These findings highlight the need for further studies to better investigate the promising properties of P. incarnata in the management of such a relevant clinical and social issue.

World Federation of Societies of Biological Psychiatry (WFSBP) guidelines for treatment of anxiety, obsessive-compulsive and posttraumatic stress disorders - Version 3. Part I: Anxiety disorders

AIM

This is the third version of the guideline of the World Federation of Societies of Biological Psychiatry (WFSBP) Task Force for the Pharmacological Treatment of Anxiety, Obsessive-Compulsive and Posttraumatic Stress Disorders (published in 2002, revised in 2008).

METHOD

A consensus panel of 33 international experts representing 22 countries developed recommendations based on efficacy and acceptability of available treatments. In total, 1007 RCTs for the treatment of these disorders in adults, adolescents, and children with medications, psychotherapy and other non-pharmacological interventions were evaluated, applying the same rigorous methods that are standard for the assessment of medications.

RESULT

This paper, Part I, contains recommendations for the treatment of panic disorder/agoraphobia (PDA), generalised anxiety disorder (GAD), social anxiety disorder (SAD), specific phobias, mixed anxiety disorders in children and adolescents, separation anxiety and selective mutism. Selective serotonin reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRIs) are first-line medications. Cognitive behavioural therapy (CBT) is the first-line psychotherapy for anxiety disorders. The expert panel also made recommendations for patients not responding to standard treatments and recommendations against interventions with insufficient evidence.

CONCLUSION

It is the goal of this initiative to provide treatment guidance for these disorders that has validity throughout the world.

Integrating Harm Reduction into Outpatient Opioid Use Disorder Treatment Settings : Harm Reduction in Outpatient Addiction Treatment

Opioid use disorder (OUD) is increasingly recognized as a chronic, relapsing brain disease whose treatment should be integrated into primary care settings alongside other chronic conditions. However, abstinence from all non-prescribed substance use continues to be prioritized as the only desired goal in many outpatient, primary care-based treatment programs. This presents a barrier to engagement for patients who continue to use substances and who may be at high risk for complications of ongoing substance use such as human immunodeficiency virus (HIV), hepatitis C virus (HCV), superficial and deep tissue infections, and overdose. Harm reduction aims to reduce the negative consequences of substance use and offers an alternative to abstinence as a singular goal. Incorporating harm reduction principles into primary care treatment settings can support programs in engaging patients with ongoing substance use and facilitate the delivery of evidence-based screening and prevention services. The objective of this narrative review is to describe strategies for the integration of evidence-based harm reduction principles and interventions into outpatient, primary care-based OUD treatment settings. We will offer specific tools for providers and programs including strategies to support safer injection practices, assess the risks and benefits of continuing medications for opioid use disorder in the setting of ongoing substance use, promote a non-stigmatizing program culture, and address the needs of special populations with ongoing substance use including adolescents, parents, and families.

Methodological Recommendations to Control for Factors Influencing Dream and Nightmare Recall in Clinical and Experimental Studies of Dreaming

In order to ensure robust relationships between the dependent and independent variables in clinical dream/nightmare studies, the major factors which influence the frequency of reported dreams must be controlled. This article sets out methodological recommendations to both researchers seeking to ensure the equivalence of experimental groups of participants in group-matching designs, and to clinicians who wish to check that any change in frequency of reported nightmares over the course of a psychological or a pharmacological intervention is not caused by factors other than the experimental treatment itself. The main factors influencing the frequency of dream recall are presented: demographic variables, psychological characteristics, pathological dimensions, and substance consumption. A series of questionnaires is proposed for easily measuring these control variables.

Selective serotonin reuptake inhibitors and benzodiazepines in panic disorder: A meta-analysis of common side effects in acute treatment

BACKGROUND

Benzodiazepines (BZs) and selective serotonin reuptake inhibitors (SSRIs) are effective in the pharmacologic treatment of panic disorder (PD). However, treatment guidelines favor SSRIs over BZs based on the belief that BZs are associated with more adverse effects than SSRIs. This belief, however, is currently supported only by opinion and anecdotes.

AIM

The aim of this review and meta-analysis was to determine if there truly is evidence that BZs cause more adverse effects than SSRIs in acute PD treatment.

METHODS

We systematically searched Web of Science, PubMed, Cochrane Central Register of Controlled Trials, and clinical trials register databases. Short randomized clinical trials of a minimum of four weeks and a maximum of 12 weeks that studied SSRIs or BZs compared to placebo in acute PD treatment were included in a meta-analysis. The primary outcome was all-cause adverse event rate in participants who received SSRIs, BZs, or placebo.

RESULTS

Overall, the meta-analysis showed that SSRIs cause more adverse events than BZs in short-term PD treatment. Specifically, SSRI treatment was a risk factor for diaphoresis, fatigue, nausea, diarrhea, and insomnia, whereas BZ treatment was a risk factor for memory problems, constipation, and dry mouth. Both classes of drugs were associated with somnolence. SSRIs were associated with abnormal ejaculation, while BZs were associated with libido reduction. BZs were protective against tachycardia, diaphoresis, fatigue, and insomnia.

CONCLUSION

Randomized, blinded studies comparing SSRIs and BZs for the short-term treatment of PD should be performed. Clinical guidelines based on incontrovertible evidence are needed.

Exploring characteristics associated with first benzodiazepine prescription in patients with affective disorders and related diagnoses

OBJECTIVE

In patients with affective disorders, benzodiazepines (BZDs) are frequently administered at the onset, sometimes inappropriately. We sought to identify clinical variables associated with first BZD prescription in a large sample of patients with affective disorders.

METHODS

Four hundred sixty patients with mood or anxiety disorders attending different psychiatric services were assessed comparing those who received BZD as first treatment (BZD w/) and those who did not (BZD w/o).

RESULTS

More than one third (35.7%) of the total sample had received BZDs as first prescription. In relation to mood disorders, BZD w/ subjects more frequently (a) had not a psychiatrist as first therapist, (b) had anxious symptoms at onset, (c) had adjustment disorder as first diagnosis, (d) were treated as outpatients. In relation to specific diagnoses, (a) personal decision of treatment for major depressive disorder, (b) outpatient status for bipolar disorder and (c) longer duration of untreated illness for adjustment disorder were more frequently associated with first BZD prescription. For anxiety disorders, the presence of stressful life events and the diagnoses of panic disorder or specific phobias were more frequently observed in BZD w/ patients.

CONCLUSION

Patients with affective disorders frequently received BZDs as first prescription with significant differences between and within mood and anxiety disorders.

Prolonged clonazepam-induced withdrawal symptoms in an NAT2 ultraslow acetylator

Clonazepam undergoes nitroreduction to 7-amino-clonazepam via CYP3A4/5, followed by acetylation to 7-acetamido-clonazepam via NAT2 enzyme. While no pharmacological activity is attributed to the metabolites of clonazepam, 7-amino-clonazepam has some affinity for the benzodiazepine receptor as a partial agonist for the gamma aminobutyric acid-A receptor and can compete with clonazepam. Interindividual variability in the incidence of adverse events in patients may, in part, be attributable to differences in clonazepam metabolism. Here, we report on a case of a 70-year-old Caucasian female with insomnia and difficulty weaning off long-term use of clonazepam suggesting that a slow acetylator phenotype contributing to patient's presentation. This hypothesis was confirmed by NAT2 gene sequencing. NAT2 genotyping may play a role in guiding clonazepam therapy.

Are there advances in pharmacotherapy for panic disorder? A systematic review of the past five years

INTRODUCTION

Several effective medications are available for treating panic disorder (PD). However, outcomes are unsatisfactory in a number of patients, suggesting the usefulness of expanding the array of antipanic drugs and improving the quality of response to current recommended treatments.

AREAS COVERED

The authors have performed an updated systematic review of pharmacological studies (phase III onwards) to examine whether advances have been made in the last five years. Only four studies were included. D-cycloserine no longer seemed promising as a cognitive-behavioral therapy (CBT) enhancer. Some preliminary findings concerning the optimization of recommended medications deserved consideration, including: the possibility that SSRIs are more effective than CBT alone in treating panic attacks, combined therapy is preferable when agoraphobia is present, and clonazepam is more potent than paroxetine in decreasing panic relapse.

EXPERT OPINION

Given the lack of novel treatments, expanding a personalized approach to the existing medications seems to be the most feasible strategy to improve pharmacotherapy outcomes regarding PD. Recent technological progress, including wearable devices collecting real-time data, 'big data' platforms, and application of machine learning techniques might help make outcome prediction more reliable. Further research on previously promising novel treatments is also recommended.

Would induction of dopamine homeostasis via coupling genetic addiction risk score (GARS®) and pro-dopamine regulation benefit benzodiazepine use disorder (BUD)?

Prescriptions for Benzodiazepines (BZDs) have risen continually. According to national statistics, the combination of BZDs with opioids has increased since 1999. BZDs (sometimes called “benzos”) work to calm or sedate a person by raising the level of the inhibitory neurotransmitter GABA in the brain. In terms of neurochemistry, BZDs act at the GABAA receptors to inhibit excitatory neurons, reducing VTA glutaminergic drive to reduce dopamine release at the Nucleus accumbens. Benzodiazepine Use Disorder (BUD) is very difficult to treat, partly because BZDs are used to reduce anxiety which paradoxically induces hypodopaminergia. Considering this, we are proposing a paradigm shift. Instead of simply targeting chloride channel direct GABAA receptors for replacement or substitution therapy, we propose the induction of dopamine homeostasis. Our rationale is supported by the well-established notion that the root cause of drug and non-drug addictions (i.e. Reward Deficiency Syndrome [RDS]), at least in adults, involve dopaminergic dysfunction and heightened stress. This proposition involves coupling the Genetic Addiction Risk Score (GARS) with a subsequent polymorphic matched genetic customized Pro-Dopamine Regulator known as KB220ZPBM (Precision Behavioral Management). Induction of dopamine homeostasis will be clinically beneficial in attempts to combat BUD for at least three reasons: 1) During detoxification of alcoholism, the potential induction of dopamine regulation reduces the need for BZDs; 2) A major reason for BZD abuse is because people want to achieve stress reduction and subsequently, the potential induction of dopamine regulation acts as an anti-stress factor; and 3) BUD and OUD are known to reduce resting state functional connectivity, and as such, potential induction of dopamine regulation enhances resting state functional connectivity. Future randomized placebo-controlled studies will investigate this forward thinking proposed novel modality.

A 6-Year Posttreatment Follow-up of Panic Disorder Patients: Treatment With Clonazepam Predicts Lower Recurrence Than Treatment With Paroxetine

BACKGROUND

The aim of this study was to identify factors associated with relapse in panic disorder (PD).

METHODS

This was an observational study conducted in the outpatient clinic of a psychiatric hospital in Rio de Janeiro, Brazil. In a previous study, 120 patients diagnosed as having PD according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria were randomized to receive clonazepam or paroxetine. After 3 years, treatment was discontinued in patients who had achieved remission. These subjects were included in the current study and were followed up for 6 years. The follow-up assessments were made at 1, 2, 3, 5, and 6 years after treatment discontinuation. Assessment included the number of panic attacks per month, Clinical Global Impression-Severity, and other measures. Patients who had initiated psychotherapy or pharmacological treatment because of PD symptoms or who had Clinical Global Impression-Severity scores greater than 1 or panic attacks in the month preceding the assessment were considered relapse cases. Data were collected from January 2003 to August 2012.

RESULTS

Eighty-five patients completed the follow-up. Cumulative relapse rates were 50% (n = 33) at 1 year and 89.4% (n = 76) at 6 years. One-year relapse rates were lower in patients previously treated with clonazepam (P = 0.001) compared with those treated with paroxetine. Low 6-year relapse rates were associated with high Hamilton Anxiety Rating Scale scores before treatment (P = 0.016) and previous treatment with clonazepam.

CONCLUSIONS

Relapse is a frequent problem in PD, and long-term treatment does not protect these patients in the long run. Treatment with clonazepam predicts lower relapse when compared with paroxetine.

Optimization of Clonazepam Therapy Adjusted to Patient's CYP3A Status and NAT2 Genotype

BACKGROUND

The shortcomings of clonazepam therapy include tolerance, withdrawal symptoms, and adverse effects such as drowsiness, dizziness, and confusion leading to increased risk of falls. Inter-individual variability in the incidence of adverse events in patients partly originates from the differences in clonazepam metabolism due to genetic and nongenetic factors.

METHODS

Since the prominent role in clonazepam nitro-reduction and acetylation of 7-amino-clonazepam is assigned to CYP3A and N-acetyl transferase 2 enzymes, respectively, the association between the patients' CYP3A status (CYP3A5 genotype, CYP3A4 expression) or N-acetyl transferase 2 acetylator phenotype and clonazepam metabolism (plasma concentrations of clonazepam and 7-amino-clonazepam) was evaluated in 98 psychiatric patients suffering from schizophrenia or bipolar disorders.

RESULTS

The patients' CYP3A4 expression was found to be the major determinant of clonazepam plasma concentrations normalized by the dose and bodyweight (1263.5±482.9 and 558.5±202.4ng/mL per mg/kg bodyweight in low and normal expressers, respectively, P<.0001). Consequently, the dose requirement for the therapeutic concentration of clonazepam was substantially lower in low-CYP3A4 expresser patients than in normal expressers (0.029±0.011 vs 0.058±0.024mg/kg bodyweight, P<.0001). Furthermore, significantly higher (about 2-fold) plasma concentration ratio of 7-amino-clonazepam and clonazepam was observed in the patients displaying normal CYP3A4 expression and slower N-acetylation than all the others.

CONCLUSION

Prospective assaying of CYP3A4 expression and N-acetyl transferase 2 acetylator phenotype can better identify the patients with higher risk of adverse reactions and can facilitate the improvement of personalized clonazepam therapy and withdrawal regimen.

Pilot trial of gabapentin for the treatment of benzodiazepine abuse or dependence in methadone maintenance patients

BACKGROUND

Benzodiazepine use disorders are a common clinical problem among methadone maintenance treatment patients and have adverse effects on clinical outcomes.

OBJECTIVES

To evaluate gabapentin for the outpatient treatment of benzodiazepine abuse or dependence in methadone maintenance patients.

METHODS

Participants (n = 19) using benzodiazepines at least 4 days per week were enrolled into an 8-week randomized double-blind placebo-controlled outpatient pilot trial. All participants received a manual-guided supportive psychotherapy aimed to promote abstinence. Study medication was titrated over a 2-week period to a maximum dose of gabapentin 1200 mg or placebo three times a day. Benzodiazepine use was assessed using urine toxicology confirmed self-report. Benzodiazepines were not provided as part of study participation; participants were provided guidance to gradually reduce benzodiazepine intake.

RESULTS

Sixteen participants had post-randomization data for analysis. Retention at week eight was 50%. The mean dose of gabapentin achieved by titration was 2666 mg/day (SD = ± 1446). There were no significant between group differences on benzodiazepine use outcomes (amount benzodiazepine per day [Mann-Whitney U = 27, p = 0.745], abstinent days per week [U = 28, p = 0.811]) and Clinical Instrument Withdrawal Assessment (CIWA)-benzodiazepines scale (U = 29.0, p = 0.913). One participant in the gabapentin group discontinued study medication because of peripheral edema. Two participants in the placebo group requested admission for inpatient detoxification treatment.

CONCLUSION

In outpatient methadone-maintained patients with benzodiazepine use disorder, gabapentin did significantly decrease benzodiazepine use relative to placebo. The small sample recruited for this trial may have limited the ability to detect a group difference.

Long-Term Pharmacological Treatments of Anxiety Disorders: An Updated Systematic Review

Many aspects of long-term pharmacological treatments for anxiety disorders (AnxDs) are still debated. We undertook an updated systematic review of long-term pharmacological studies on panic disorder (PD), generalized anxiety disorder (GAD), and social anxiety disorder (SAD). Relevant studies dating from January 1, 2012 to August 31, 2015 were identified using the PubMed database and a review of bibliographies. Of 372 records identified in the search, five studies on PD and 15 on GAD were included in the review. No studies on SAD were found. Our review confirms the usefulness of long-term pharmacological treatments for PD and GAD and suggests that they can provide further improvement over that obtained during short-term therapy. Paroxetine, escitalopram, and clonazepam can be effective for long-term treatment of PD. However, further studies are needed to draw conclusions about the long-term benzodiazepine use in PD, particularly for the possible cognitive side-effects over time. Pregabalin and quetiapine can be effective for long-term treatment of GAD, while preliminary suggestions emerged for agomelatine and vortioxetine. We did not find any evidence for determining the optimal length and/or dosage of medications to minimize the relapse risk. Few investigations have attempted to identify potential predictors of long-term treatment response. Personalized treatments for AnxDs can be implemented using predictive tools to explore those factors affecting treatment response/tolerability heterogeneity, including neurobiological functions/clinical profiles, comorbidity, biomarkers, and genetic features, and to tailor medications according to each patient's unique features.

Deprescribing benzodiazepines and Z-drugs in community-dwelling adults: a scoping review

BACKGROUND

Long-term sedative use is prevalent and associated with significant morbidity, including adverse events such as falls, cognitive impairment, and sedation. The development of dependence can pose significant challenges when discontinuation is attempted as withdrawal symptoms often develop. We conducted a scoping review to map and characterize the literature and determine opportunities for future research regarding deprescribing strategies for long-term benzodiazepine and Z-drug (zopiclone, zolpidem, and zaleplon) use in community-dwelling adults.

METHODS

We searched PubMed, Cochrane Central Register of Controlled Trials, EMBASE, PsycINFO, CINAHL, TRIP, and JBI Ovid databases and conducted a grey literature search. Articles discussing methods for deprescribing benzodiazepines or Z-drugs in community-dwelling adults were selected.

RESULTS

Following removal of duplicates, 2797 articles were reviewed for eligibility. Of these, 367 were retrieved for full-text assessment and 139 were subsequently included for review. Seventy-four (53%) articles were original research, predominantly randomized controlled trials (n = 52 [37%]), whereas 58 (42%) were narrative reviews and seven (5%) were guidelines. Amongst original studies, pharmacologic strategies were the most commonly studied intervention (n = 42 [57%]). Additional deprescribing strategies included psychological therapies (n = 10 [14%]), mixed interventions (n = 12 [16%]), and others (n = 10 [14%]). Behaviour change interventions were commonly combined and included enablement (n = 56 [76%]), education (n = 36 [47%]), and training (n = 29 [39%]). Gradual dose reduction was frequently a component of studies, reviews, and guidelines, but methods varied widely.

CONCLUSIONS

Approaches proposed for deprescribing benzodiazepines and Z-drugs are numerous and heterogeneous. Current research in this area using methods such as randomized trials and meta-analyses may too narrowly encompass potential strategies available to target this phenomenon. Realist synthesis methods would be well suited to understand the mechanisms by which deprescribing interventions work and why they fail.

Information for physicians and pharmacists about drugs that might cause dry mouth: a study of monographs and published literature

BACKGROUND

Over three-quarters of the older population take medications that can potentially cause dry mouth. Physicians or pharmacists rarely inform patients about this adverse effect and its potentially severe damage to the teeth, mouth and general health.

OBJECTIVES

The objectives of this study were to (1) identify warnings in the literature about dry mouth associated with the most frequently prescribed pharmaceutical products in Canada; and (2) consider how this information might be obtained by physicians, pharmacists and patients.

METHODS

Monographs on the 72 most frequently prescribed medications during 2010 were retrieved from the Compendium of Pharmaceuticals and Specialties (CPS, a standard drug information reference for physicians and pharmacists), the National Library of Medicine's 'DailyMed' database, directly from the manufacturers, and from a systematic search of biomedical journals.

RESULTS

The CPS provided monographs for 43% of the medications, and requests to manufacturers produced the remaining monographs. Mentions of dry mouth were identified in 61% of the products (43% amongst CPS monographs; an additional 43% amongst manufacturers' monographs; 7% in the DailyMed database and 7% from biomedical journals); five medications had contradictory reports in different monographs.

CONCLUSION

Nearly two-thirds (61%) of the most commonly prescribed medications can cause dry mouth, yet warnings about this adverse effect and its potentially serious consequences are not readily available to physicians, pharmacists, dentists or patients.

Contextos e padrões do uso indevido de benzodiazepínicos entre mulheres

O uso indevido de benzodiazepínicos, especialmente entre mulheres, tem despertado preocupação na área de saúde pública. Este estudo objetivou compreender qualitativamente crenças e valores associados ao consumo indevido dessa substância por mulheres. Foram entrevistadas trinta e três mulheres (18-60 anos) com histórico de uso indevido de benzodiazepínicos no último ano, selecionadas intencionalmente e por critérios. Os discursos foram transcritos e submetidos à análise de conteúdo com auxílio do software NVivo. A maioria das entrevistadas referiu tempo de uso bem superior ao recomendado (mediana: 7 anos) e compra com receita médica. Os motivos de uso mais citados foram diminuição da ansiedade, problemas de insônia e fuga dos problemas. Apesar de reconhecerem a possibilidade de dependência, esta não motivou a interrupção do uso. O acompanhamento médico não pareceu, necessariamente, estimular a percepção de risco dos benzodiazepínicos, sendo um fator que favoreceu a manutenção do uso prolongado.

The role of alprazolam for the treatment of panic disorder in Australia

OBJECTIVE

To investigate the potential impact of increasing prescription rates of alprazolam for the treatment of panic disorder (PD) in Australia through a review of efficacy, tolerability and adverse outcome literature.

METHODS

Data were sourced by a literature search using MEDLINE, Embase, PsycINFO and a manual search of scientific journals to identify relevant articles. Clinical practice guidelines from the American Psychiatric Association, National Institute of Clinical Excellence, Royal Australian and New Zealand College of Psychiatrists and World Federation of Societies of Biological Psychiatry were sourced. Prescription data were sourced from Australian governmental sources.

RESULTS

Alprazolam has shown efficacy for control of PD symptoms, particularly in short-term controlled clinical trials, but is no longer recommended as a first-line pharmacological treatment due to concerns about the risks of developing tolerance, dependence and abuse potential. Almost no evidence is available comparing alprazolam to current first-line pharmacological treatment. Despite this, prescription rates are increasing. A number of potential issues including use in overdose and impact on car accidents are noted. conclusion: Although effective for PD symptoms in clinical trials, a number of potential issues may exist with use. Consideration of its future place in PD treatment in Australia may be warranted.

A randomized, naturalistic, parallel-group study for the long-term treatment of panic disorder with clonazepam or paroxetine

This long-term extension of an 8-week randomized, naturalistic study in patients with panic disorder with or without agoraphobia compared the efficacy and safety of clonazepam (n = 47) and paroxetine (n = 37) over a 3-year total treatment duration. Target doses for all patients were 2 mg/d clonazepam and 40 mg/d paroxetine (both taken at bedtime). This study reports data from the long-term period (34 months), following the initial 8-week treatment phase. Thus, total treatment duration was 36 months. Patients with a good primary outcome during acute treatment continued monotherapy with clonazepam or paroxetine, but patients with partial primary treatment success were switched to the combination therapy. At initiation of the long-term study, the mean doses of clonazepam and paroxetine were 1.9 (SD, 0.30) and 38.4 (SD, 3.74) mg/d, respectively. These doses were maintained until month 36 (clonazepam 1.9 [SD, 0.29] mg/d and paroxetine 38.2 [SD, 3.87] mg/d). Long-term treatment with clonazepam led to a small but significantly better Clinical Global Impression (CGI)-Improvement rating than treatment with paroxetine (mean difference: CGI-Severity scale -3.48 vs -3.24, respectively, P = 0.02; CGI-Improvement scale 1.06 vs 1.11, respectively, P = 0.04). Both treatments similarly reduced the number of panic attacks and severity of anxiety. Patients treated with clonazepam had significantly fewer adverse events than those treated with paroxetine (28.9% vs 70.6%, P < 0.001). The efficacy of clonazepam and paroxetine for the treatment of panic disorder was maintained over the long-term course. There was a significant advantage with clonazepam over paroxetine with respect to the frequency and nature of adverse events.

The efficacy and safety of alprazolam versus other benzodiazepines in the treatment of panic disorder

We performed a meta-analysis of all single- or double-blind, randomized controlled trials comparing alprazolam to another benzodiazepine in the treatment of adult patients meeting the Diagnostic and Statistical Manual of Mental Disorders, Third or Fourth Edition, criteria for panic disorder or agoraphobia with panic attacks. Eight studies met inclusion criteria, describing a total of at least 631 randomized patients. In the pooled results, there were no significant differences in efficacy between alprazolam and the comparator benzodiazepines on any of the prespecified outcomes: improvement in mean panic attack frequency (between-arm weighted mean difference of 0.6 panic attacks per week; 95% confidence interval [CI], -0.3 to 1.6), improvement in Hamilton Anxiety Rating Scale score (weighted mean difference of 0.8 points; 95% CI, -0.5 to 2.1), and proportion of patients free of panic attacks at the final evaluation (pooled relative risk, 1.1; 95% CI, 0.9-1.4). Statistical heterogeneity on prespecified outcomes was not eliminated by stratification on baseline anxiety level. The available evidence fails to demonstrate alprazolam as superior to other benzodiazepines for the treatment of panic disorder.

Efficacy of chronic antidepressant treatments in a new model of extreme anxiety in rats

Animal models of anxious disorders found in humans, such as panic disorder and posttraumatic stress disorder, usually include spontaneous and conditioned fear that triggers escape and avoidance behaviors. The development of a panic disorder model with a learned component should increase knowledge of mechanisms involved in anxiety disorders. In our ethological model of extreme anxiety in the rat, forced apnea was combined with cold water vaporization in an inescapable situation. Based on the reactions of vehicle controls, behaviors involved in paroxysmic fear were passive (freezing) and active (jumping) reactions. Our results show that subchronic fluoxetine (5 mg/kg, IP, 21 days) and imipramine (10 mg/kg, IP, 14 days) administration alleviated freezing and jumping behaviors, whereas acute fluoxetine (1 mg/kg, IP) provoked opposite effects. Acute low dose of diazepam (1 mg/kg, IP) was not effective, whereas the higher dose of 3 mg/kg, IP, and clonazepam (1 mg/kg, IP) only had an effect on jumping. Paroxysmic fear generated in this experimental condition may therefore mimic the symptomatology observed in patients with anxiety disorders.