ABSTRACT
OBJECTIVE: Catatonia is a neuropsychiatric disorder associated with changes in behavior and affect. In adults, catatonia can respond rapidly to treatment with benzodiazepines as part of the "lorazepam challenge test." The acute effectiveness of benzodiazepine treatment in pediatric catatonia, however, has received less study. This study reports catatonia severity as measured by the Bush Francis Catatonia Rating Scale (BFCRS) in pediatric patients before and after treatment with lorazepam. METHODS: Multicenter retrospective cohort study from 1/1/2018 to 6/1/2023 of patients aged 18 and younger with a clinical diagnosis of catatonia and assessment using the BFCRS before and after treatment with lorazepam. RESULTS: Among 54 patients, median age was 16, and 26 (48.1 %) were female. Neurodevelopmental disabilities were present in 24 (44.4 %) of patients. Prior to treatment, patients had a mean BFCRS score of 16.6 ± 6.1, which significantly reduced to 9.5 ± 5.3 following treatment with lorazepam (mean paired difference 7.1; t = 9.0, df = 53, p < 0.001), representing a large effect size (Hedges's g = 1.20; 95 % CI: 0.85 to 1.55). No significant association was found between lorazepam dose or route of administration and clinical response, nor were age, sex, study site, the presence of a neurodevelopmental disorder, the presence of hyperactive catatonic features, or the time between treatment and reassessment associated with post-treatment BFCRS. CONCLUSIONS: Lorazepam resulted in a rapid improvement in BFCRS score in pediatric patients, with a large effect size. Further research is needed into optimal dosing and route of administration of the lorazepam challenge test in pediatric patients.
Subject(s)
Catatonia , Lorazepam , Humans , Lorazepam/administration & dosage , Lorazepam/pharmacology , Lorazepam/therapeutic use , Female , Male , Catatonia/drug therapy , Catatonia/diagnosis , Retrospective Studies , Adolescent , Child , Child, Preschool , Treatment Outcome , Severity of Illness IndexABSTRACT
BACKGROUND: Dysfunctional sensory gating in anxiety disorders, indexed by the failure to inhibit the P50 event-related potential (ERP) to repeated stimuli, has been linked to deficits in the major inhibitory neurotransmitter γ-aminobutyric acid (GABA). AIMS/METHODS: This study, conducted in 30 healthy volunteers, examined the acute effects of GABAA (lorazepam: 1 mg) and GABAB receptor (baclofen: 10 mg) agonists on P50 measures of auditory sensory gating within a paired-stimulus (S1-S2) paradigm and assessed changes in gating in relation to self-ratings of anxiety. RESULTS: Compared to placebo, lorazepam reduced ERP indices of sensory gating by attenuating response to S1. Although not directly impacting P50 inhibition, baclofen-induced changes in gating (relative to placebo) were negatively correlated with trait but not state anxiety. CONCLUSIONS: These preliminary findings support the involvement of GABA in sensory gating and tentatively suggest a role for GABAB receptor signaling in anxiety-associated gating dysregulation.
Subject(s)
Anxiety , Baclofen , GABA-B Receptor Agonists , Lorazepam , Receptors, GABA-B , Sensory Gating , Humans , Male , Female , Adult , Baclofen/pharmacology , Lorazepam/pharmacology , GABA-B Receptor Agonists/pharmacology , Anxiety/metabolism , Young Adult , Sensory Gating/drug effects , Receptors, GABA-B/metabolism , Receptors, GABA-B/drug effects , GABA-A Receptor Agonists/pharmacology , Healthy Volunteers , Double-Blind Method , Evoked Potentials, Auditory/drug effects , Evoked Potentials, Auditory/physiology , Receptors, GABA-A/metabolism , Receptors, GABA-A/drug effects , AdolescentABSTRACT
BACKGROUND: Anxiety disorders are highly prevalent and socio-economically costly. Novel pharmacological treatments for these disorders are needed because many patients do not respond to current agents or experience unwanted side effects. However, a barrier to treatment development is the variable and large placebo response rate seen in trials of novel anxiolytics. Despite this, the mechanisms that drive placebo responses in anxiety disorders have been little investigated, possibly due to low availability of convenient experimental paradigms. We aimed to develop and test a novel protocol for inducing placebo anxiolysis in the 7.5% CO2 inhalational model of generalized anxiety in healthy volunteers. METHODS: Following a baseline 20-minute CO2 challenge, 32 healthy volunteers were administered a placebo intranasal spray labelled as either the anxiolytic "lorazepam" or "saline." Following this, participants surreptitiously underwent a 20-minute inhalation of normal air. Post-conditioning, a second dose of the placebo was administered, after which participants completed another CO2 challenge. RESULTS: Participants administered sham "lorazepam" reported significant positive expectations of reduced anxiety (P = .001), but there was no group-level placebo effect on anxiety following CO2 challenge post-conditioning (Ps > .350). Surprisingly, we found many participants exhibited unexpected worsening of anxiety, despite positive expectations. CONCLUSIONS: Contrary to our hypothesis, our novel paradigm did not induce a placebo response, on average. It is possible that effects of 7.5% CO2 inhalation on prefrontal cortex function or behavior in line with a Bayesian predictive coding framework attenuated the effect of expectations on subsequent placebo response. Future studies are needed to explore these possibilities.
Subject(s)
Anti-Anxiety Agents , Anxiety , Carbon Dioxide , Placebo Effect , Humans , Carbon Dioxide/administration & dosage , Carbon Dioxide/pharmacology , Male , Female , Adult , Young Adult , Anti-Anxiety Agents/pharmacology , Anti-Anxiety Agents/administration & dosage , Administration, Inhalation , Anxiety/drug therapy , Anxiety/chemically induced , Lorazepam/pharmacology , Lorazepam/administration & dosage , Double-Blind MethodABSTRACT
BACKGROUND: Phenobarbital has been used in the emergency department (ED) as both a primary and adjunctive medication for alcohol withdrawal, but previous studies evaluating its impact on patient outcomes are limited by heterogenous symptom severity. OBJECTIVES: We compared the clinical outcomes of ED patients with moderate alcohol withdrawal who received phenobarbital, with or without benzodiazepines, with patients who received benzodiazepine treatment alone. METHODS: This is a retrospective cohort study conducted at a single academic medical center utilizing chart review of ED patients with moderate alcohol withdrawal between 2015 and 2020. Patient encounters were classified into two treatment categories based on medication treatment: phenobarbital alone or in combination with benzodiazepines vs. benzodiazepines alone. Chi-square test or Fisher's exact was used to analyze categorical variables and the Student's t-test for continuous data. RESULTS: Among the 287 encounters that met inclusion criteria, 100 received phenobarbital, compared with 187 that received benzodiazepines alone. Patients who received phenobarbital were provided significantly more lorazepam equivalents. There was a significant difference in the percentage of patient encounters that required admission to the hospital in the phenobarbital cohort compared with the benzodiazepine cohort (75% vs. 43.3%, p < 0.001). However, there was no difference in admission level of care to the floor (51.2% vs. 52.0%), stepdown (33.8% vs. 28%), or intensive care unit (15% vs. 20%), respectively. CONCLUSIONS: Patients who received phenobarbital for moderate alcohol withdrawal were more likely to be admitted to the hospital, but there was no difference in admission level of care when compared with patients who received benzodiazepines alone. Patients who received phenobarbital were provided greater lorazepam equivalents in the ED.
Subject(s)
Alcoholism , Substance Withdrawal Syndrome , Humans , Benzodiazepines/pharmacology , Benzodiazepines/therapeutic use , Substance Withdrawal Syndrome/drug therapy , Retrospective Studies , Lorazepam/pharmacology , Lorazepam/therapeutic use , Phenobarbital/pharmacology , Phenobarbital/therapeutic use , Emergency Service, HospitalABSTRACT
Previous neuroscientific research has expounded on the fundamental role played by emotion during moral decision-making. Negative emotionality has been observed to exert a general inhibitory effect towards harmful behaviors against others. Nevertheless, the downregulation of negative affects at different levels of moral processing (e.g. impersonal versus personal moral dilemmas) alongside its possible interactions with other factors (e.g. perspective taking) hasn't been directly assessed; both of which can assist in predicting future moral decision-making. In the present research, we empirically test (Study 1, N = 41) whether downregulating negative emotionality through pharmacological interventions using lorazepam (a GABA receptor agonist), modulate the permissibility of harm to others -i.e. if participants find it more morally permissible to harm others when harm is unavoidable (inevitable harm moral dilemmas), than when it may be avoided (evitable harm moral dilemmas). Furthermore, using another sample (Study 2, N = 31), we assess whether lorazepam's effect is modulated by different perspective-taking conditions during a moral dilemma task -e.g. "is it morally permissible for you to [ ]?" (1st person perspective), relative to "is it morally permissible for [x individual] to [ ]?" (3rd person perspective)-, where the outcome of the different scenarios is controlled. The results of both studies converge, revealing an emotion-dependent, rather than an outcome-dependent, pharmacological modulation. Lorazepam only influenced interpersonal moral judgments when not modulated by the evitable/inevitable condition. Furthermore, there was a significant interaction between perspective-taking and drug administration, as lorazepam exerted a larger effect in modulating moral choices rather than moral judgements.
Subject(s)
Judgment , Lorazepam , Humans , Judgment/physiology , Lorazepam/pharmacology , Down-Regulation , Emotions , MoralsABSTRACT
Animals need to cope with abundant sensory information, and one strategy is to selectively direct attention to only the most relevant part of the environment. Although the cortical networks of selective attention have been studied extensively, its underlying neurotransmitter systems, especially the role of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), remain less well understood. Increased GABAA receptor activity because of administration of benzodiazepines such as lorazepam is known to slow reactions in cognitive tasks. However, there is limited knowledge about GABAergic involvement in selective attention. Particularly, it is unknown whether increased GABAA receptor activity slows the build-up of selectivity or generally widens attentional focus. To address this question, participants (n = 29) received 1 mg lorazepam and placebo (within-subjects, double-blind) and performed an extended version of the flanker task. The spatial distribution of selective attention was studied by systematically manipulating number and position of incongruent flankers; the temporal build-up was characterized using delta plots. An online task version was presented to an independent, unmedicated sample (n = 25) to verify task effects. Under placebo and in the unmedicated sample, only the number of incongruent flankers, but not their position, influenced RTs. Incongruent flankers impaired RTs more strongly under lorazepam than placebo, especially when adjacent to the target. Delta plot analyses of RT showed that this effect persisted even when participants reacted slowly, indicating that lorazepam-induced impairments in selective attention do not result from simply slowed down build-up of selectivity. Instead, our data indicate that increased GABAA receptor activity widens the attentional focus.
Subject(s)
Attention , GABA Modulators , Receptors, GABA-A , Double-Blind Method , Lorazepam/pharmacology , Receptors, GABA-A/drug effects , Receptors, GABA-A/metabolism , Humans , Attention/drug effects , Attention/physiology , GABA Modulators/pharmacologyABSTRACT
OBJECTIVE: Prolonged and repetitive cycles of pharmacological coma, with midazolam or other general anaesthetics, is often the mainstay for seizure control in febrile infection-related epilepsy syndrome (FIRES). Here we present our experience of enteral lorazepam as an effective weaning substitute in midazolam-dependent patients. METHODS: This was a retrospective study based on a review of medical records of all FIRES patients who had received enteral lorazepam as a weaning substitute for midazolam, between January 2020 and July 2021. The patients were divided into an early group (lorazepam initiated after one failed attempt to wean off midazolam) and late group (lorazepam initiated after two or more failed attempts). The conversion from intravenous midazolam to enteral lorazepam was also calculated, and epilepsy outcome at follow-up was also assessed. RESULTS: Seven patients (five males) were eligible. The median age at onset of FIRES was seven years (range: 4-14). A median of six (range: 6-8) anti-seizure medications (ASMs) had failed (including clobazam in two and clonazepam in one) to control seizures. The early and late lorazepam groups were comparable regarding the maximum midazolam dose for seizure control, total ASMs tried and days to wean off midazolam. The median (range) duration of hospital stay was 27 days (22-46) in the early group, compared to 51 days (40-78) in the late group. The early group patients were also on fewer ASMs (median: 3;range: 3-5) compared to the late group (median: 5; range: 4-6) at discharge. Five patients were sedated with initial lorazepam dose, but this side effect resolved on dosage reduction. On follow-up, all seven patients had seizure recurrence. In four, seizures recurred on reducing lorazepam, however, in three of these patients, this was resolved by escalating the dose. SIGNIFICANCE: Enteral lorazepam can be an effective weaning substitute for midazolam-dependent children with FIRES. Early introduction of enteral lorazepam was associated with reduced duration of hospital stay.
Subject(s)
Drug Resistant Epilepsy , Encephalitis , Epileptic Syndromes , Child , Humans , Lorazepam/pharmacology , Lorazepam/therapeutic use , Male , Midazolam/therapeutic use , Retrospective Studies , WeaningABSTRACT
BACKGROUND: Antipsychotic and sedative combinations are commonly used for treating agitation in the emergency department despite limited evidence regarding their comparative safety and efficacy. OBJECTIVES: To compare the efficacy and safety of combination haloperidol, lorazepam, and diphenhydramine (B52) to combination haloperidol and lorazepam (52) in treating acute agitation. METHODS: This multicenter, retrospective cohort study included adult patients ≥ 18 years of age who received either B52 or 52 at a Banner Health facility between August 2017 and September 2020. Patients were excluded if they had a pre-existing movement disorder or were withdrawing from alcohol. The primary outcome was administration of additional agitation medication(s) within 2 h of B52 or 52. Secondary outcomes included incidence of extrapyramidal symptoms, length of stay, and additional safety measures. RESULTS: There was no difference in administration frequency of additional agitation medication(s) (B52: n = 28 [14%] vs. 52: n = 40 [20%]; p = 0.11). Patients who received 52 were more likely to require an antimuscarinic medication within 2 days (15 vs. 6 patients, p = 0.04). Of the patients who received an antimuscarinic medication, none had documented extrapyramidal symptoms. The 52 group had shorter length of stay (13.8 vs. 17 h; p = 0.03), lower incidence of hypotension (7 vs. 32 patients; p < 0.001), and oxygen desaturation (0 vs. 6 patients; p = 0.01), and fewer physical restraints (53 vs. 86 patients; p = 0.001) compared with the B52 group. CONCLUSIONS: Both the B52 and 52 combinations infrequently required repeat agitation medication; however, the B52 combination resulted in more oxygen desaturation, hypotension, physical restraint use, and longer length of stay.
Subject(s)
Antipsychotic Agents , Hypotension , Adult , Antipsychotic Agents/therapeutic use , Diphenhydramine/pharmacology , Diphenhydramine/therapeutic use , Haloperidol/pharmacology , Haloperidol/therapeutic use , Humans , Hypotension/drug therapy , Lorazepam/pharmacology , Lorazepam/therapeutic use , Muscarinic Antagonists/therapeutic use , Oxygen/therapeutic use , Psychomotor Agitation/drug therapy , Retrospective StudiesABSTRACT
AIMS: The purpose of this study was to investigate pharmacodynamic effects of drugs targeting cortical excitability using transcranial magnetic stimulation (TMS) combined with electromyography (EMG) and electroencephalography (EEG) in healthy subjects, to further develop TMS outcomes as biomarkers for proof-of-mechanism in early-phase clinical drug development. Antiepileptic drugs presumably modulate cortical excitability. Therefore, we studied effects of levetiracetam, valproic acid and lorazepam on cortical excitability in a double-blind, placebo-controlled, 4-way cross-over study. METHODS: In 16 healthy male subjects, single- and paired-pulse TMS-EMG-EEG measurements were performed predose and 1.5, 7 and 24 hours postdose. Treatment effects on motor-evoked potential, short and long intracortical inhibition and TMS-evoked potential amplitudes, were analysed using a mixed model ANCOVA and cluster-based permutation analysis. RESULTS: We show that motor-evoked potential amplitudes decreased after administration of levetiracetam (estimated difference [ED] -378.4 µV; 95%CI: -644.3, -112.5 µV; P < .01), valproic acid (ED -268.8 µV; 95%CI: -532.9, -4.6 µV; P = .047) and lorazepam (ED -330.7 µV; 95%CI: -595.6, -65.8 µV; P = .02) when compared with placebo. Long intracortical inhibition was enhanced by levetiracetam (ED -60.3%; 95%CI: -87.1%, -33.5%; P < .001) and lorazepam (ED -68.2%; 95%CI: -94.7%, -41.7%; P < .001) at a 50-ms interstimulus interval. Levetiracetam increased TMS-evoked potential component N45 (P = .004) in a central cluster and decreased N100 (P < .001) in a contralateral cluster. CONCLUSION: This study shows that levetiracetam, valproic acid and lorazepam decrease cortical excitability, which can be detected using TMS-EMG-EEG in healthy subjects. These findings provide support for the use of TMS excitability measures as biomarkers to demonstrate pharmacodynamic effects of drugs that influence cortical excitability.
Subject(s)
Lorazepam , Transcranial Magnetic Stimulation , Biomarkers , Cross-Over Studies , Electroencephalography , Humans , Levetiracetam/pharmacology , Lorazepam/pharmacology , Male , Pharmaceutical Preparations , Valproic Acid/pharmacologyABSTRACT
Aging is associated with cognitive impairment, but there are large individual differences in these declines. One neural measure that is lower in older adults and predicts these individual differences is moment-to-moment brain signal variability. Testing the assumption that GABA should heighten neural variability, we examined whether reduced brain signal variability in older, poorer performing adults could be boosted by increasing GABA pharmacologically. Brain signal variability was estimated using fMRI in 20 young and 24 older healthy human adults during placebo and GABA agonist sessions. As expected, older adults exhibited lower signal variability at placebo, and, crucially, GABA agonism boosted older adults' variability to the levels of young adults. Furthermore, poorer performing older adults experienced a greater increase in variability on drug, suggesting that those with more to gain benefit the most from GABA system potentiation. GABA may thus serve as a core neurochemical target in future work on aging- and cognition-related human brain dynamics.SIGNIFICANCE STATEMENT Prior research indicates that moment-to-moment brain signal variability is lower in older, poorer performing adults. We found that this reduced brain signal variability could be boosted through GABA agonism in older adults to the levels of young adults and that this boost was largest in the poorer performing older adults. These results provide the first evidence that brain signal variability can be restored by increasing GABAergic activity and suggest the promise of developing interventions targeting inhibitory systems to help slow cognitive declines in healthy aging.
Subject(s)
Aging/physiology , Brain/drug effects , Cognition/drug effects , GABA Modulators/pharmacology , Lorazepam/pharmacology , Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Magnetic Resonance Imaging , Male , Young AdultABSTRACT
The proton-sensing receptor, ovarian cancer G protein-coupled receptor (OGR1), has been shown to be expressed in airway smooth muscle (ASM) cells and is capable of promoting ASM contraction in response to decreased extracellular pH. OGR1 knockout (OGR1KO) mice are reported to be resistant to the asthma features induced by inhaled allergen. We recently described certain benzodiazepines as OGR1 activators capable of mediating both procontractile and prorelaxant signaling in ASM cells. Here we assess the effect of treatment with the benzodiazepines lorazepam or sulazepam on the asthma phenotype in wild-type (WT) and OGR1KO mice subjected to inhaled house dust mite (HDM; Dermatophagoides pteronyssius) challenge for 3 wk. In contrast to previously published reports, both WT and OGR1KO mice developed significant allergen-induced lung inflammation and airway hyperresponsiveness (AHR). In WT mice, treatment with sulazepam (a Gs-biased OGR1 agonist), but not lorazepam (a balanced OGR1 agonist), prevented allergen-induced AHR, although neither drug inhibited lung inflammation. The protection from development of AHR conferred by sulazepam was absent in OGR1KO mice. Treatment of WT mice with sulazepam also resulted in significant inhibition of HDM-induced collagen accumulation in the lung tissue. These findings suggest that OGR1 expression is not a requirement for development of the allergen-induced asthma phenotype, but OGR1 can be targeted by the Gs-biased OGR1 agonist sulazepam (but not the balanced agonist lorazepam) to protect from allergen-induced AHR, possibly mediated via suppression of chronic bronchoconstriction and airway remodeling in the absence of effects on airway inflammation.
Subject(s)
Allergens/toxicity , Asthma/pathology , Bronchial Hyperreactivity/pathology , Bronchoconstriction , Cytokines/metabolism , Pneumonia/pathology , Receptors, G-Protein-Coupled/physiology , Animals , Anti-Anxiety Agents/pharmacology , Asthma/etiology , Asthma/metabolism , Benzodiazepines/pharmacology , Bronchial Hyperreactivity/etiology , Bronchial Hyperreactivity/metabolism , Female , Lorazepam/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Phenotype , Pneumonia/etiology , Pneumonia/metabolism , PyroglyphidaeABSTRACT
BACKGROUND: Inhibitory control is a crucial executive function with high relevance to mental and physical well-being. However, there are still unanswered questions regarding its neural mechanisms, including the role of the major inhibitory neurotransmitter, γ-aminobutyric acid (GABA). AIMS: This study examined the effects of lorazepam (0.5 mg and 1 mg), a positive allosteric modulator at the GABAA receptor, on response inhibition and interference control. We also explored the heterogeneity of inhibitory control and calculated delta plots to explore whether lorazepam affects the gradual build-up of inhibition and activation over time. METHODS: N = 50 healthy participants performed antisaccade, Eriksen flanker and Simon tasks in a within-subjects, placebo-controlled, double-blind randomized design. RESULTS: Lorazepam increased reaction time (RT) and error rates dose dependently in all tasks (p ⩽ 0.005). In the antisaccade and Simon tasks, lorazepam increased congruency effects for error rate (p ⩽ 0.029) but not RT (p ⩾ 0.587). In the Eriksen flanker task, both congruency effects were increased by the drug (p ⩽ 0.031). Delta plots did not reflect drug-induced changes in inhibition and activation over time. Delta plots for RT in the Simon task were negative-going, as expected, whereas those for the antisaccade and flanker tasks were positive-going. CONCLUSIONS: This study provides evidence for GABAergic involvement in performance on response inhibition and interference control tasks. Furthermore, our findings highlight the diversity of the broader construct of inhibitory control while also pointing out similarities between different inhibitory control tasks. In contrast to RT and error rates, the cognitive processes indexed by delta plots may not be sensitive to GABAergic modulation.
Subject(s)
Attention/drug effects , Executive Function/drug effects , GABA Agents/pharmacology , Inhibition, Psychological , Lorazepam/pharmacology , Psychomotor Performance/drug effects , Adult , Double-Blind Method , Female , Humans , Male , Receptors, GABA-A/drug effects , Young AdultABSTRACT
BACKGROUND: Cognitive decline after oral administration of sedatives, such as benzodiazepines, is a serious side effect. Suvorexant, an orexin receptor antagonist, has a favorable tolerability and a limited side-effect profile. AIM: The purpose of this study was to estimate the cognitive decline 1 day after oral medication with lormetazepam, a benzodiazepine, and suvorexant by comparing mismatch negativity (MMN) and P300 reflecting auditory discrimination function. METHODS: Sixty healthy subjects (42 males) were randomly assigned to three groups receiving suvorexant 20 mg, lormetazepam 2 mg, or placebo in this double-blind, randomized control study. Event-related potential recordings during an auditory oddball task and a digit symbol substitution test (DSST) were performed 1 day after oral administration. RESULTS: MMN, on the day after oral administration, was significantly attenuated in the lormetazepam group compared with the other two groups, but there was no difference between the suvorexant and placebo groups. No significant difference was found in P300 amplitudes and DSST scores among the three groups. CONCLUSION: These findings suggest that suvorexant, unlike benzodiazepine, is not associated with cognitive deficits, as revealed by MMN but not P300. This study shows a neurophysiological difference in the effects of suvorexant and benzodiazepine on cognitive function.
Subject(s)
Auditory Perception/drug effects , Azepines/pharmacology , Benzodiazepines/pharmacology , Cognitive Dysfunction/chemically induced , Discrimination, Psychological/drug effects , Evoked Potentials, Auditory/drug effects , Lorazepam/analogs & derivatives , Orexin Receptor Antagonists/pharmacology , Triazoles/pharmacology , Adult , Azepines/administration & dosage , Azepines/adverse effects , Benzodiazepines/administration & dosage , Benzodiazepines/adverse effects , Electroencephalography , Event-Related Potentials, P300/drug effects , Female , Humans , Lorazepam/administration & dosage , Lorazepam/adverse effects , Lorazepam/pharmacology , Male , Orexin Receptor Antagonists/administration & dosage , Orexin Receptor Antagonists/adverse effects , Triazoles/administration & dosage , Triazoles/adverse effects , Young AdultABSTRACT
BACKGROUND: Previous studies have suggested that evening intake of benzodiazepine affects blood pressure (BP) and/or heart rate (HR) in healthy and hypertensive subjects. The aim of this study was to compare the effect of chronic oral administration of alprazolam and lorazepam as hypnotics on ambulatory BP and HR in patients with mild hypertension. METHODS: Consecutive outpatients of both sexes with newly diagnosed, never-treated mild hypertension were randomized, after a 4-week placebo run-in period, to receive alprazolam 0.5 mg plus placebo, lorazepam 1 mg plus placebo, or placebo plus placebo for 2 weeks in 3 crossover periods, each separated by a 1-week placebo wash-out period. At the end of the initial placebo run-in and of each treatment period, 24-hour ambulatory BP and HR monitoring was performed using a noninvasive device. RESULTS: In the 32 patients, no treatment had any effect on 24-hour and daytime systolic BP (SBP), diastolic BP (DBP), and HR, which remained unchanged. During the nighttime, SBP and DBP values were unaffected by alprazolam, as compared with placebo, whereas DBP was significantly higher after treatment with lorazepam (+3.7%, P < 0.05 vs placebo). Nocturnal HR mean values were significantly increased by lorazepam (+10.1%, P < 0.01 vs placebo), whereas they did not change after alprazolam. CONCLUSIONS: In patients with mild hypertension, oral intake of alprazolam or lorazepam as hypnotics did not affect ambulatory BP or HR values. A slight increase in nighttime DBP was observed with lorazepam, whereas alprazolam showed no effect on nocturnal BP and HR, probably reflecting a stimulating effect of the drug on central α2-receptors.
Subject(s)
Alprazolam/pharmacology , Blood Pressure/drug effects , Hypnotics and Sedatives/pharmacology , Lorazepam/pharmacology , Administration, Oral , Alprazolam/administration & dosage , Cross-Over Studies , Double-Blind Method , Female , Heart Rate/drug effects , Humans , Hypertension/physiopathology , Hypnotics and Sedatives/administration & dosage , Lorazepam/administration & dosage , Male , Middle Aged , Time FactorsABSTRACT
BACKGROUND: Silexan is a lavender essential oil with established anxiolytic and calming efficacy. Here we asked whether there is a potential for abuse in human patients. METHODS: We carried out a phase I abuse liability single-center, double-blind, 5-way crossover study in healthy users of recreational central nervous system depressants. They received single oral doses of 80 mg (therapeutic dose) and 640 mg Silexan, 2 mg and 4 mg lorazepam (active control) and placebo in randomized order, with 4- to 14-day washout periods between treatments. Pharmacodynamic measures included validated visual analogue scales assessing positive, negative, and sedative drug effects and balance of effects; a short form of the Addiction Research Center Inventory; and a drug similarity assessment. The primary outcome measure was the individual maximum value on the drug liking visual analogue scale during 24 hours post-dose. RESULTS: Forty participants were randomized and 34 were evaluable for pharmacodynamic outcomes. In intraindividual head-to-head comparisons of the drug liking visual analogue scale maximum value, both doses of Silexan were rated similar to placebo whereas differences were observed between Silexan and lorazepam and between placebo and lorazepam (P < .001). These data were supported by all secondary measures of positive drug effects and of balance of effects. Differences between placebo and both doses of Silexan were always negligible in magnitude. Moreover, Silexan showed no sedative effects and was not perceived to be similar to commonly used drugs that participants had used in the past. CONCLUSIONS: Silexan did not exhibit any abuse potential in a standard abuse potential detection screen study and is unlikely to be recreationally abused.
Subject(s)
Anti-Anxiety Agents/pharmacology , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Recreational Drug Use , Adolescent , Adult , Anti-Anxiety Agents/administration & dosage , Central Nervous System Depressants/administration & dosage , Cross-Over Studies , Double-Blind Method , Humans , Lavandula , Lorazepam/pharmacology , Middle Aged , Oils, Volatile/administration & dosage , Plant Oils/administration & dosage , Substance-Related Disorders/diagnosis , Young AdultABSTRACT
This study aimed at better understanding the neurochemistry underlying transcranial magnetic stimulation (TMS) and magnetic resonance spectroscopy (MRS) measurements as it pertains to GABAergic activity following administration of allosteric GABAA receptor agonist lorazepam. Seventeen healthy adults (8 females, 26.0⯱â¯5.4â¯years old) participated in a double-blind, crossover, placebo-controlled study, where participants underwent TMS and MRS two hours after drug intake (placebo or lorazepam; 2.5â¯mg). Neuronavigated TMS measures reflecting cortical inhibition and excitation were obtained in the left primary motor cortex. Sensorimotor cortex and occipital cortex MRS data were acquired using a 3T scanner with a MEGA-PRESS sequence, allowing water-referenced [GABA] and [Glx] (glutamateâ¯+â¯glutamine) quantification. Lorazepam administration decreased occipital [GABA], decreased motor cortex excitability and increased GABAA-receptor mediated motor cortex inhibition (short intracortical inhibition (SICI)). Lorazepam intake did not modulate sensorimotor [GABA] and TMS measures of intra-cortical facilitation, long-interval cortical inhibition, cortical silent period, and resting motor threshold. Furthermore, higher sensorimotor [GABA] was associated with higher cortical inhibition (SICI) following lorazepam administration, suggesting that baseline sensorimotor [GABA] may be valuable in predicting pharmacological or neuromodulatory treatment response. Finally, the differential effects of lorazepam on MRS and TMS measures, with respect to GABA, support the idea that TMS measures of cortical inhibition reflect synaptic GABAergic phasic inhibitory activity while MRS reflects extrasynaptic GABA.
Subject(s)
Lorazepam , Motor Cortex , Adult , Evoked Potentials, Motor , Female , Humans , Lorazepam/pharmacology , Magnetic Resonance Spectroscopy , Male , Neural Inhibition , Transcranial Magnetic Stimulation , Young AdultABSTRACT
BACKGROUND: Benzodiazepines have reliable adverse effects on saccadic eye movements, but the impact of sex as a potential modulator of these effects is less clear. A recent study reported stronger adverse effects on the spatial consistency of saccades in females, which may reflect sex differences in cerebellar mechanisms. AIMS: We aimed to further examine the role of sex as a potential modulator of benzodiazepine effects by employing the saccadic adaptation paradigm, which is known to be sensitive to cerebellar functioning. METHODS: A total of n=50 healthy adults performed a horizontal step prosaccade task and a saccadic adaptation task under 0.5 mg lorazepam, 1 mg lorazepam and placebo in a double-blind, within-subjects design. RESULTS: In the prosaccade task, lorazepam had adverse effects on measures of peak velocity, latency and spatial consistency. The administration of 0.5 mg lorazepam led to significant reductions in gain-decrease adaptation, while a dose of 1 mg did not impair adaptation learning. Gain-increase adaptation was generally less pronounced, and unaffected by the drug. There were no significant drug×sex interactions in either task. CONCLUSIONS: We conclude that a low dose of lorazepam impairs gain-decrease adaptation independent of sex. At higher doses, however, increasing fatigue may facilitate adaptation and thus counteract the adverse effects observed at lower doses. With regards to prosaccades, our findings confirm peak velocity as well as latency and spatial measures as sensitive biomarkers of GABAergic effects.
Subject(s)
Lorazepam/pharmacology , Saccades , Adult , Benzodiazepines/pharmacology , Dose-Response Relationship, Drug , Eye Movement Measurements , Female , GABA Modulators/pharmacology , Healthy Volunteers , Humans , Male , Saccades/drug effects , Saccades/physiology , Sex Factors , Task Performance and AnalysisABSTRACT
RATIONALE: Benzodiazepines are useful and commonly prescribed. Unfortunately, they are associated with subtle but functionally significant neurocognitive side effects that increase the risk of motor vehicle accidents and falls. OBJECTIVE: The objective of this study was to determine whether clinically feasible measures of simple reaction time and reaction accuracy are sensitive to a single dose of lorazepam. METHODS: Using a randomized, double-blind, crossover design, 26 healthy adults (13 women; age = 26.9 ± 8.2 yr) were given 1.0 mg lorazepam or placebo 90 minutes prior to two data collection sessions. Participants completed simple and reaction accuracy tasks using a standardized "ruler drop" testing paradigm during each session. Outcomes were mean and variability of simple reaction time and reaction accuracy, which evaluates a participant's ability to catch the device solely on the random 50% of trials that lights affixed to it illuminate on release. Reaction accuracy requires a go/no-go decision within 420 ms before the falling device strikes the floor. RESULTS: As compared with placebo, lorazepam increased simple reaction time variability (range = 43 ± 18 vs. 60 ± 23 ms, respectively; p = 0.004 and standard deviation = 14.6 ± 5.7 vs. 19.7 ± 7.3 ms, respectively; = 0.006) and decreased reaction accuracy (90 ± 7% vs. 84 ± 11%, respectively; p = 0.010). CONCLUSION: Given prior work demonstrating associations between simple reaction time and reaction accuracy and functional outcomes such as self-protection, response to perturbations, and fall risk, these clinically available measures may have a role in identifying subtle, functionally significant cognitive changes related to short-term benzodiazepine use.
Subject(s)
Cognitive Dysfunction/chemically induced , Hypnotics and Sedatives/pharmacology , Lorazepam/pharmacology , Psychomotor Performance/drug effects , Reaction Time/drug effects , Adult , Cross-Over Studies , Double-Blind Method , Female , Humans , Hypnotics and Sedatives/administration & dosage , Lorazepam/administration & dosage , Male , Young AdultABSTRACT
Benzodiazepines (BZDs) represent the gold standard of anxiolytic pharmacotherapy; however, their clinical benefit is limited by side effects and addictive potential. Consequently, there is an urgent need to develop novel and safe anxiolytics. The peptide hormone oxytocin (OXT) exhibits anxiolytic-like properties in animals and humans, but whether OXT and BZDs share similar effects on the neural circuitry of fear is unclear. Therefore, the rationale of this ultra-high-field functional MRI (fMRI) study was to test OXT against the clinical comparator lorazepam (LZP) with regard to their neuromodulatory effects on local and network responses to fear-related stimuli. One hundred twenty-eight healthy male participants volunteered in this randomized double-blind, placebo-controlled, between-group study. Before scanning using an emotional face-matching paradigm, participants were randomly administered a single dose of OXT (24 IU), LZP (1 mg), or placebo. On the behavioral level, LZP, but not OXT, caused mild sedation, as evidenced by a 19% increase in reaction times. On the neural level, both OXT and LZP inhibited responses to fearful faces vs. neutral faces within the centromedial amygdala (cmA). In contrast, they had different effects on intra-amygdalar connectivity; OXT strengthened the coupling between the cmA and basolateral amygdala, whereas LZP increased the interplay between the cmA and superficial amygdala. Furthermore, OXT, but not LZP, enhanced the coupling between the cmA and the precuneus and dorsomedial prefrontal cortex. These data implicate inhibition of the cmA as a common denominator of anxiolytic action, with only OXT inducing large-scale connectivity changes of potential therapeutic relevance.
Subject(s)
Amygdala , Fear/drug effects , Lorazepam/pharmacology , Oxytocin/pharmacology , Adult , Amygdala/diagnostic imaging , Amygdala/drug effects , Amygdala/physiology , Fear/physiology , Humans , Magnetic Resonance Imaging , Male , Neurotransmitter Agents/pharmacology , Young AdultABSTRACT
Threat responses are often shaped by social information, such as observation of aversive outcomes for others. Yet, the neurochemistry regulating observational learning of threats is largely unknown. Here, we examined the impact of the GABAergic and noradrenergic system, which are central in regulating threat learning from first-hand experiences, on observational threat learning in humans. To this end, 61 participants received either 1 mg Lorazepam (enhancing GABAergic signalling N = 18), 20 mg Yohimbine (enhancing Noradrenergic transmission, N = 16), Placebo (double blind and randomized control for Lorazepam and Yohimbine, N = 12) or no treatment (N = 15) prior to observational threat conditioning. Participants acquired conditioned threat responses by observation of another individual who is presented with a conditioned stimulus (CS) and an aversive unconditioned stimulus (US). Participants' threat responses were tested by direct exposure to the CSs immediately after learning, as well as two days later (drug free). Our results indicate decreased fear ratings to socially acquired CSs by enhanced GABAergic transmission as compared to the control group (placebo and no treatment) during the immediate test. We could not provide evidence for noradrenergic modulation of socially acquired threat responses. Further, we found no differences in psychophysiological responses (Skin conductance responses) or long-term persistence of conditioned responses. Our results provide initial evidence for an impact of the GABAergic system on social acquisition of threats.