Effect of diazepam and fosazepam (a soluble derivative of diazepam) on sleep in man

Benzodiazepines and Sleep Architecture: A Systematic Review

BACKGROUND

Insomnia, defined as a difficulty in initiating or maintaining sleep, is a relevant medical issue. Benzodiazepines (BZDs) are commonly prescribed to treat insomnia. Two phases characterize human sleep structure: sleep with Non-Rapid Eye Movement (NREM) and sleep with Rapid Eye Movement (REM). Physiological sleep includes NREM and REM phases in a continuous cycle known as "Sleep Architecture."

OBJECTIVE

This systematic review summarizes the studies that have investigated effects of BZDs on Sleep Architecture.

METHODS

The articles selection included human clinical trials (in English, Portuguese, or Spanish) only, specifically focused on BZDs effects on sleep architecture. PubMed, BVS, and Google Scholar databases were searched.

RESULTS

Findings on BZDs effects on sleep architecture confirm an increase in stage 2 of NREM sleep and a decrease in time of stages 3 and 4 of NREM sleep with a reduction in time of REM sleep during the nocturnal sleep.

CONCLUSION

Variations in NREM and REM sleep may lead to deficits in concentration and working memory and weight gain. The increase in stage 2 of NREM sleep may lead to a subjective improvement of sleep quality with no awakenings. BZDz should be prescribed with zeal and professional judgment. These patients should be closely monitored for possible long-term side effects.

The Combination of Atomoxetine and Oxybutynin Greatly Reduces Obstructive Sleep Apnea Severity. A Randomized, Placebo-controlled, Double-Blind Crossover Trial

Rationale: There is currently no effective pharmacological treatment for obstructive sleep apnea (OSA). Recent investigations indicate that drugs with noradrenergic and antimuscarinic effects improve genioglossus muscle activity and upper airway patency during sleep. Objectives: We aimed to determine the effects of the combination of a norepinephrine reuptake inhibitor (atomoxetine) and an antimuscarinic (oxybutynin) on OSA severity (apnea-hypopnea index [AHI]; primary outcome) and genioglossus responsiveness (secondary outcome) in people with OSA. Methods: A total of 20 people completed a randomized, placebo-controlled, double-blind, crossover trial comparing 1 night of 80 mg atomoxetine plus 5 mg oxybutynin (ato-oxy) to placebo administered before sleep. The AHI and genioglossus muscle responsiveness to negative esophageal pressure swings were measured via in-laboratory polysomnography. In a subgroup of nine patients, the AHI was also measured when the drugs were administered separately. Measurements and Main Results: The participants' median (interquartile range) age was 53 (46-58) years and body mass index was 34.8 (30.0-40.2) kg/m2. ato-oxy lowered AHI by 63% (34-86%), from 28.5 (10.9-51.6) events/h to 7.5 (2.4-18.6) events/h (P < 0.001). Of the 15/20 patients with OSA on placebo (AHI > 10 events/hr), AHI was lowered by 74% (62-88%) (P < 0.001) and all 15 patients exhibited a ≥50% reduction. Genioglossus responsiveness increased approximately threefold, from 2.2 (1.1-4.7)%/cm H2O on placebo to 6.3 (3.0 to 18.3)%/cm H2O on ato-oxy (P < 0.001). Neither atomoxetine nor oxybutynin reduced the AHI when administered separately. Conclusions: A combination of noradrenergic and antimuscarinic agents administered orally before bedtime on 1 night greatly reduced OSA severity. These findings open new possibilities for the pharmacologic treatment of OSA. Clinical trial registered with www.clinicaltrials.gov (NCT02908529).

Broadband Sound Administration Improves Sleep Onset Latency in Healthy Subjects in a Model of Transient Insomnia

Background

Insomnia is a major public health problem in western countries. Previous small pilot studies showed that the administration of constant white noise can improve sleep quality, increase acoustic arousal threshold, and reduce sleep onset latency. In this randomized controlled trial, we tested the effect of surrounding broadband sound administration on sleep onset latency, sleep architecture, and subjective sleep quality in healthy subjects.

Methods

Eighteen healthy subjects were studied with two overnight sleep studies approximately one week apart. They were exposed in random order to normal environmental noise (40.1 [1.3] dB) or to broadband sound administration uniformly distributed in the room by two speakers (46.0 [0.9] dB). To model transient insomnia, subjects went to bed (“lights out”) 90 min before usual bedtime.

Results

Broadband sound administration reduced sleep onset latency to stage 2 sleep (time from lights out to first epoch of non-rapid eye movement-sleep stage 2) (19 [16] vs. 13 [23] min, p = 0.011; median reduction 38% baseline). In a subgroup reporting trouble initiating sleep at home (Pittsburgh Sleep Quality Index section 2 score ≥ 1), sound administration improved subjective sleep quality (p = 0.037) and the frequency of arousals from sleep (p = 0.03).

Conclusion

In an experimental model of transient insomnia in young healthy individuals, broadband sound administration significantly reduced sleep onset latency by 38% compared to normal environmental noise. These findings suggest that broadband sound administration might be helpful to minimize insomnia symptoms in selected individuals.

Effect of a metabolite of diazepam, 3-hydroxydiazepam (temazepam), on sleep in man

The effect of 3-hydroxydiazepam (temazepam, 10 mg and 20 mg) on sleep was studied in six healthy adult males using electroencephalography for sleep measures, and analogue scales for subjective assessments of well-being and sleep quality. The effects were compared with diazepam (5 mg and 10 mg). Effect on total sleep time was restricted to the night of ingestion. There was no change in total sleep time after temazepam (10 mg), but with 20 mg total sleep time was increased (P = 0.01). Sleep onset latencies and awakenings were markedly reduced. Temazepam reduced the duration (min) of stage 0 (P = 0.05) and stage 1 (P = 0.01) sleep, and the effect on stage 1 was seen during each two hourly interval of sleep (P = 0.05). No effects were observed with stage 3, 3+4 and REM sleep, except that the appearance of the first REM period was delayed with temazepam (20 mg) (P = 0.001). The subjects, as a group, reported improved sleep, but subjective assessments of well-being were not altered. Correlations were calculated for sleep measures and subjective assessments.

A dose response study of the hypnotic effectiveness of alprazolam and diazepam in normal subjects

One group of eight normal young males was administered three doses of alprazolam (0.25, 0.5 and 1.0 mg) and placebo, while a second group of eight normal young males was given three doses of diazepam (2, 5, and 10 mg) and placebo in the same design. All subjects slept in the sleep laboratory for 10 nights, 2 consecutive nights each week for 5 consecutive weeks. The first 2 nights served as adaptation. During the next 4 weeks subjects received a random dose of alprazolam (or placebo) or a random dose of diazepam (or placebo) each week. Similar dose-related benzodiazepine effects were found on sleep with both medications. Alprazolam reduced percent stage 4 and REM sleep and increased stage 2 sleep and latency to REM. Diazepam decreased percent stage 1 and increased percent stage 2 sleep. No drug by dose interactions were found. It was concluded that, while both drugs had similar effects on sleep, alprazolam showed significant effects on REM sleep parameters and might be evaluated for possible antidepressant effect.

The use of short- and long-acting hypnotics in clinical medicine

1 Activity of short- and long-acting benzodiazepines is reviewed with reference to pharmacokinetics and residual sequelae, and to efficacy and adverse effects. 2 Some benzodiazepines may not lead to obvious effects on performance, such as nordiazepam and clobazam, and the persistence of residual sequelae may not relate obviously to elimination half-lives (as with diazepam and possibly flunitrazepam). However, benzodiazepines with mean half-lives less than 8 h may have residual sequelae, whereas hypnotics with mean half-lives greater than 16 h are likely to lead to impared performance and/or anxiolytic effects the next day. 3 Potassium chlorazepate 15 mg, with its long-acting metabolite nordiazepam, would seem to be the drug of choice for insomnia secondary to anxiety. For the insomniac without significant psychopathology, temazepam 10-20 mg, triazolam 0.125-0.25 mg and for occasional use, diazepam 5-10 mg, provide the initial approach. Flurazepam hydrochloride 15-30 mg, nitrazepam 5-10 mg and flunitrazepam 1 mg and above, have persistent residual effects and should be reserved for refractory patients, and for those in whom some impairment of performance the next day would be acceptable. 4 There is little or no evidence to suggest that the proper use of the short-acting hypnotics, triazolam and temazepam, leads to a worsening of sleep on withdrawal. However, some benzodiazepines may lead to disturbances of sleep and/or rebound insomnia, and nitrazepam and flunitrazepam may be implicated.

Studies on sleep and performance with a triazolo-1, 4-thienodiazepine (brotizolam)

1 Brotizolam, a triazolo-1,4-thienodiazepine, was studied in healthy young adults. Electroencephalographic sleep variables and subjective effects, and performance on a visuo-motor coordination task were measured. 2 In the sleep studies six males each ingested 0.2, 0.4 and 0.6 mg brotizolam overnight. All doses increased total sleep time, improved the sleep efficiency index, and reduced drowsy sleep and number of awakenings. Brotizolam 0.4 and 0.6 mg also reduced awake activity and increased stage 2 sleep. There was some evidence of a delay to the first REM period, but only 0.6 mg reduced the total duration of REM sleep. There were no changes in slow wave sleep. 3. In the performance studies six females each ingested 0.4 mg in the morning and 0.2, 0.4 and 0.6 mg brotizolam at night. After morning ingestion of 0.4 mg there was impaired performance from 0.5 to 5.5 h. There were no residual effects after 0.2 mg brotizolam, but with 0.4 mg there was a residual effect at 9.5 h, and 0.6 mg led to impairments up to 15.0 h after ingestion. 4 Brotizolam is a short-acting hypnotic. In doses around 0.2 mg it has useful hypnotic activity free of adverse effects on sleep and residual effects on performance. With 0.4 mg the hypnotic effect is enhanced with only minimal residual effects.

Activity of the hypnotics, flunitrazepam and triazolam, in man

1 Effects of flunitrazepam and triazolam (0.25 and 0.5 mg) on sleep and on performance were studied in six healthy adult males. Sleep was assessed by electroencephalography and analogue scales, and performance by a visuo-motor coordination task.

2 Over the same dose range triazolam had a more pronounced effect than flunitrazepam. Total sleep time was increased by 0.25 and 0.5 mg triazolam, and by 0.5 mg flunitrazepam. Both drugs decreased awake activity and drowsy sleep, though the effect of flunitrazepam was limited to the 0.5 mg dose and restricted to the first 6 h after sleep onset. There were no changes in slow wave sleep.

3 Latency to the first period of rapid eye movement (REM) sleep was increased with 0.5 mg triazolam, and when doses were combined (0.25-0.5 mg) the latencies with both drugs were increased. Both doses of triazolam reduced the duration and percentage of REM sleep during the early part of the night, though the whole night duration of REM sleep was not changed.

4 After the morning ingestion of 0.25 mg flunitrazepam performance was impaired for 2.0 h, but there were no residual effects when 0.25 or 0.5 mg were taken at night. With the morning ingestion of 0.25 mg triazolam performance was impaired from 0.5 to at least 5.0 h after ingestion. There were no residual effects with 0.25 mg overnight, but with 0.5 mg triazolam there was an effect on performance 10 h after ingestion with recovery within 1.5 h (11.5 h of ingestion).

5 Triazolam (0.25 mg) and 0.5 mg flunitrazepam provide useful hypnotic activity when impaired performance the next day is to be avoided. The activity of 0.5 mg triazolam is accompanied by only limited residual sequelae compared with some other benzodiazepines of comparable efficacy, and so may prove to be useful when a more powerful effect is required.

The Leeds Sleep Evaluation Questionnaire in psychopharmacological investigations - a review

The Leeds Sleep Evaluation Questionnaire comprises ten self-rating 100-mm-line analogue questions concerned with aspects of sleep and early morning behaviour. The questionnaire has been used to monitor subjectively perceived changes in sleep during psychopharmacological investigations involving a variety of psychoactive agents, including sedative-hypnotics, antidepressants, anxiolytics, CNS stimulants, and antihistamines. Dose-related improvements in the self-reported ratings of getting to sleep and perceived quality of sleep were generally associated with reductions in the self-reported levels of alertness and behavioural integrity the morning following the nocturnal administration of sedative hypnotic and anti-anxiety agents. Psychostimulants on the other hand, impaired subjective ratings of sleep and produced increases in early morning assessments of alertness. Certain antidepressant and antihistaminic agents produced effects similar to the sedative-hypnotics, while others did not affect self-reported aspects of sleep and early morning behaviour.

Comparison of diazepam and flurazepam in the treatment of insomnia in general practice

In a double-blind crossover study in general practice, flurazepam was shown to be significantly better (p less than 0.001) than diazepam in treating sleep disturbance. Fewer patients reported side-effects on flurazepam.

Differential effects of the 1,4 and 1,5 benzodiazepines on performance in healthy man

1 The immediate and residual effects on performance of benzodiazepines differ, and the differences are important in the use of these drugs. 2. Diazepam and its hydroxylated metabolites, temazepam and oxazepam, each possess hypnotic activity, and have effects on performance limited to the sleep period. The demethylated metabolite of diazepam, nordiazepam, and its precursor, potassium clorazepate, which also possess hypnotic activity, have a longer duration of action, although the next day anxiolytic effect is accompanied by only minimal effects on performance. The 1.5 benzodiazepine, clobazam, seems to have minimal immediate effects on performance. 3 Diazepam and its hydroxylated metabolites, temazepam and oxazepam, would be useful in the management of insomnia without psychopathology in those cases in which residual effects on performance must be avoided. Nordiazepam and potassium clorazepate would be appropriate for insomnia secondary to day-time anxiety, and clobazam may be useful as a day-time anxiolytic. 4 It is emphasized that more work needs to be carried out on the effects of anxiolytics on performance before one can be certain that ingestion during the day would be without any deleterious effects on skilled work.

Immediate and residual effects in man of the metabolites of diazepam

1 Immediate and residual effects of diazepam and its metabolites on visuomotor co-ordination have been studied in man. Performance was observed from 10.0-16.0 h after overnight ingestion of diazepam (5 and 10 mg), temazepam (10, 20 and 30 mg), oxazepam (15, 30 and 45 mg) and nordiazepam (5 and 10 mg), and from 0.5-6.5 h after morning ingestion of diazepam (10 mg), temazepam (20 mg), oxazepam (30 mg), and nordiazepam (5 and 10 mg). Immediate and residual effects of diazepam and temazepam were also studied on a choice response time test.

2 Visuo-motor co-ordination was not impaired after the overnight ingestion of 5 and 10 mg diazepam, 10, 20 and 30 mg temazepam, 15 and 30 mg oxazepam and 5 and 10 mg nordiazepam, though there was a trend of impaired performance over the dose range used with temazepam 10.0 h after ingestion. With 45 mg oxazepam performance at 10.0 h was impaired compared with performance at 14.0 (P < 0.01) and 16.0 h (P < 0.001). Performance on the choice response time test was not impaired after the overnight ingestion of 5 and 10 mg diazepam and 10, 20 and 30 mg temazepam.

3 With morning ingestion visuo-motor co-ordination was impaired at 0.5 (P < 0.01) and 2.5 h (P < 0.05) after 10 mg diazepam, at 0.5 (P < 0.001) after 20 mg temazepam, and at 2.5 (P < 0.01) and 4.5 h (P < 0.05) after 30 mg oxazepam. Performance 6.5 h after 10 mg nordiazepam was impaired compared with performance 0.5 and 2.5 h (P < 0.01) after ingestion. Performance on the choice response time test was impaired 1.0 h after ingestion of 10 mg diazepam (P < 0.01) and 20 mg temazepam (P < 0.05).

4 It is considered that diazepam (5-10 mg), temazepam (10-20 mg) and oxazepam (15-30 mg) would be useful hypnotics within the dose ranges indicated, at least for occasional use, when impaired performance the next day would be unacceptable. The studies with nordiazepam suggest that, though this drug may have limited effects on performance, it may have persistent effects on behaviour consistent with its clinical use as an anxiolytic.

Performance studies with antihistamines

1 Effect of four antihistamines, chlorpheniramine (4 mg), clemastine (1 mg), promethazine (10 mg) and terfenadine (60 mg), on visuo-motor coordination and on subjective assessments of performance and well-being were compared with placebo in six healthy females from 0.5--7.0 h after morning ingestion of each drug. The study was double-blind, and the doses used were believed to be equally potent in their antihistaminic activity. 2 There was impaired performance 1.5 h (P less than 0.01) after chlorpheniramine, 3.0 h (P less than 0.05) and 5.0 h (P less than 0.01) after clemastine, and 3.0 h (P less than 0.01) and 5.0 h (P less than 0.001) after promethazine. It was not possible to establish effects on performance after ingestion of terfenadine. Subjective assessments of performance were not altered. 3 The subjects as a group reported improved alertness (P less than 0.05) and improved wakefulness (P less than 0.05) 0.5 h and 3.5 h respectively after ingestion of terfenadine, and were less energetic (P less than 0.05) 7.0 h after ingestion of chlorpheniramine. There were not other consistent changes in assessments of well-being.

Clazepam: pharmacokinetics and effects on performance

1. The effects of clazepam, a new benzodiazepine (30 mg orally) on performance tests and the cardiovascular system have been compared to those of chlordiazepoxide (30 mg orally) and a placebo in a double-blind trial involving six healthy volunteers. Simultaneously, the pharmacokinetics of clazepam were investigated. 2. While clazepam itself could be detected neither in plasma nor in urine, it gave rise to two plasma metabolites, the former, an alcoholic derivative with a short half-life, and the second, desmethyldiazepam, with a long half-life. These two metabolites and oxazepam were excreted in urine and, within the 24 h period following drug intake, accounted for 73% of the ingested dose. 3. Seven hours after its administration, clazepam slightly improved performance and reduced anxiety. The kinetics of these effects and the metabolic data suggest that clazepam acts mainly through the formation of desmethyldiazepam. However, owing to the low blood levels of this metabolite, the activity of clazepam was very moderate.

Efficacy and side effects of flurazepam, fosazepam, and nitrazepam as sleeping aids in psychogeriatric patients

Efficacy and side effects of flurazepam 15 mg, fosazepam 60 mg, and nitrazepam 5 mg were studied in 17 psychogeriatric patients. The drugs were equipotent in maintaining sleep but nitrazepam had more side effects than the other hypnotics, and it induced a rebound insomnia after withdrawal. All hypnotics lost some of their efficacy towards the end of 7 days' administration. Patients with evident cerebrovascular disease were vulnerable to the side effects of the benzodiazepine hypnotics. The side effects did not correlate with the age of a patient. In addition, no correlations were found between the serum levels of fosazepam or its main metabolite and the side effects.

Behavioural and pharmacokinetic studies in the monkey (Macaca mulatta) with diazepam, nordiazepam and related 1,4-benzodiazepines

1. Behavioural activity (delayed differentiation and spatial delayed alternation) and pharmacokinetics of diazepam and its metabolites, N-desmethyldiazepam (nordiazepam), 3-hydroxydiazepam (temazepam) and 3-hydroxy-N-desmethyldiazepam (oxazepam), and of dipotassium clorazepate (clorazepate), were studied in the monkey (Macaca mulatta). Diazepam and its metabolites (1.8 and 3.0 mg/kg) and clorazepate (2.6 and 4.3 mg/kg) were given by intraperitoneal injection. 2. Hydroxylation of diazepam (temazepam and oxazepam) led to a loss of, or a considerable reduction in, behavioural activity, whereas activity was preserved, though modified, by demethylation (nordiazepam). It was not possible to establish change in behaviour at specific time intervals after clorazepate, but combined performance data revealed an effect. 3. The maximum mean plasma concentrations of diazepam, temazepam, oxazepam and clorazepate were observed at 0.5 h, and the maximum mean plasma concentration of nordiazepam was observed at 1 hour. Plasma concentrations of nordiazepam were the highest and decreased monoexponentially. Plasma concenqrations of the other drugs declined rapidly at first but more slowly later, and these data were analysed as biexponential models. In the analysis for metabolites, nordiazepam reached measurable levels after the injection of diazepam and clorazepate. 4. It is suggested that differences in the effects of closely related benzodiazepines may not be due solely to their plasma pharmacokinetic properties, but may arise from differences in their intrinsic activity.

Evaulation of the effect of fosazepam (a new benzodiazepine), nitrazepam and placebo on sleep patterns in normal subjects

The nocturnal sleep of eight healthy young volunteers was studied after placebo, Fosazepam 100 mg and Nitrazepam 10 mg. Overall results were very similar after the two drugs. During drug periods there was less of sleep Stages I, III + IV and REM, compensated by an increase in Stage II. The decrease in SWS (III + IV) persisted during the withdrawal periods. There was also an increase in Stage I during Fosazepam withdrawal, whereas the percentage of other sleep stages returned to normal. Sleep quality was reported to be slightly better and morning drowsiness, as well as hangover effects, were said to be less pronounced after Fosazepam than after Nitrazepam.

Effect of the 1,5-benzodiazepines, clobazam and triflubazam, on sleep in man

1 The effect of the 1,5-benzodiazepines, clobazam (10 and 20 mg) and triflubazam (20 and 40 mg), on sleep was studied in six healthy males using electroencephalography for sleep measures and analogue scales for subjective assessments of well being and sleep quality. The effect of clobazam was limited to the night of ingestion. There was some evidence from subjective assessments that the effect of triflubazam may have persisted beyond the night of ingestion. 2 No effect of clobazam or triflubazam was observed on total sleep time, stage shifts in the first 6 h or latency to the first rapid eye movement period of sleep. With clobazam sleep onset latency was shortened (P less than 0.05), but this effect was not seen with triflubazam. The latency to stage 3 was shortened by both drugs. There was evidence of reduced duration of awake (stage 0) activity and drowsy (stage 1) sleep with both drugs. 3 The percentage stage 1 sleep was reduced by clobazam (10 and 20 mg) and by triflubazam (20 mg) (P less than 0.05), though the effect was not significant with triflubazam (40 mg). Clobazam (20 mg) increased the percentage stage 2 sleep (P less than 0.05), but reduced the percentage stage 3 (P less than 0.01) and stages 3 + 4 (P less than 0.05) sleep. There were no other effects on percentage of total sleep time occupied by various sleep stages or in duration (min) of sleep stages, except that the duration (min) of sleep stages, except that the duration (min) of stage 2 sleep in the second 2 h interval of sleep was increased with clobazam (20 mg) (P less than 0.01). 4 Subjects reported impaired sleep with triflubazam (40 mg) (P less than 0.05), and a sense of less wakefulness the morning after ingestion of clobazam (10 and 20 mg) (P less than 0.01) and triflubazam (40 mg) (P less than 0.05).