Hypnotics. Their place in therapeutics

Limitations on the use of benzodiazepines in anxiety and insomnia: are they justified?

The benzodiazepines are still extensively used in psychiatry, neurology and medicine in general. Anxiety disorder and severe insomnia are important syndromal indications, but these drugs are widely prescribed at the symptomatic level, resulting in potential overuse. The official data sheets recommend short durations of usage and conservative dosage. Although short-term efficacy is established, long-term efficacy remains controversial, as relevant data are scanty and relapse, rebound and dependence on withdrawal not clearly distinguished. The risks of the benzodiazepines are well-documented and comprise psychological and physical effects. Among the former are subjective sedation, paradoxical release of anxiety and/or hostility, psychomotor impairment, memory disruption, and risks of accidents. Physical effects include vertigo, dysarthria, ataxia with falls, especially in the elderly. Dependence can supervene on long-term use, occasionally with dose escalation. The benzodiazepines are now recognised as major drugs of abuse and addiction. Other drug and non-drug therapies are available and have a superior risk benefit ratio in long-term use. It is concluded that benzodiazepines should be reserved for short-term use--up to 4 weeks--and in conservative dosage.

Usage patterns of benzodiazepines in a Dutch community: a 10-year follow-up

Only a few longitudinal studies have addressed benzodiazepine use over time. We therefore conducted a 10-year follow-up study (1983-1992) on usage patterns of benzodiazepines in a Dutch community of 13 500 people. Use decreased during the time of the study. Twelve (1983) to ten (1992) percent of the inhabitants was a recipient at least once a year of a benzodiazepine prescription. The use by gender showed more women using more prescriptions as men. Women were not prescribed more DDDs per prescription as men. Individual benzodiazepines showed differences in use by gender. Use increased with age among both women and men. Most of the users were 55 years or older. One out of three patients was either an incidental user (1-30 days use in one calendar year), a regular (31-180 days), or a long term user (more than 180 days). The use of long half-life hypnotics decreased, the use of the short half-life ones showed an increase. Behind a stable overall trend we found strong fluctuations in use of individual benzodiazepines.

Hypnotic drug use in Spain: a cross-sectional study based on a network of community pharmacies. Spanish Group for the Study of Hypnotic Drug Utilization

OBJECTIVE

To investigate how hypnotic drugs are used in Spain, specifically, (1) to characterize the user population in some simple demographic (e.g., sex, age) and clinical (e.g., type of insomnia, type of physician who prescribed the drug) variables; (2) to estimate the proportion of long-term users (> 3 mo); (3) to determine the frequency of different administration schedules; (4) to determine whether the kind of hypnotic drug prescribed according to the duration of its effect correlates with the type of sleep disorder or patient age; and (5) to compare the dosage used by the elderly with that used by adults.

DESIGN

Cross-sectional pharmacy-based study.

SETTING

A network of 318 community pharmacies throughout Spain.

SUBJECTS

Patients (n = 5324) requesting a hypnotic drug for insomnia who agreed to take part in the study.

MAIN OUTCOME MEASURES

Distribution of the use of hypnotic drugs by age, sex, type of insomnia, type of physician, specific hypnotic drug, daily dosage, treatment schedule, and duration of treatment.

RESULTS

Women (67%) and the elderly (58%) constituted the largest subgroups in the sample. Difficulties in sleep onset and in sleep maintenance as single disorders were reported by 38% and 37% of users, respectively. Prescriptions were written by general practitioners in 80% of cases. Daily use was reported by 88% and long-term use (> 3 mo) by 72% of the users. Long-term treatment was two- to threefold more frequent in the elderly than in middle-aged subjects. Intermediate-action hypnotic drugs were used by 59% of subjects, short-action drug by 24%, and long-action drugs by 17%. The type of hypnotic drug prescribed was not related to the kind of sleep disorder or the age of patients. Specialists prescribed long-action hypnotic drugs more often than did general practitioners. No relevant differences were observed between dosages used by the elderly and those used by adults. In both groups the dosage taken by most patients, regardless of the drug, corresponded to the available strength. Substitution drugs for triazolam belonged to the intermediate-action class in 53% of the cases.

CONCLUSIONS

Recommendations on hypnotic drug use are largely not followed in Spain. Most patients are taking hypnotic drugs daily, over long time periods, and without an adequate dosage titration according to age. Measures should be taken to correct this situation.

A new design of trial for hypnotics comparison: a double-blind cross-over trial with patient's preference assessment and continuation of the preferred treatment

1. This study compared two hypnotics administrated at comparable therapeutic dosages: triazolam (0.25 mg) and loprazolam (1 mg), were administered using an original scheme (cross-over on the first 2 nights, and continuation of the preferred treatment or new randomization). 2. Sixty-seven outpatients complaining of common insomnia participated in this study conducted by general practitioners. 3. Both drugs provided improvement in sleep quality (decreased sleep latency, increased total duration of sleep, decreased number of night awakenings), and are equally well tolerated. 4. For the first 2 nights, triazolam was evaluated to be more efficient than loprazolam (p < 0.001), and patients felt more rested the following day (p < 0.01) with the former drug. Moreover, triazolam is more frequently preferred than loprazolam by 47.7% and 29.2%, respectively, (p = 0.09). 5. No interaction was found between treatment and order of administration or specific effects and order of administration.

Pharmacotherapy of insomnia: practice and prospects

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

Pharmacokinetics and brain distribution of zolpidem in the rat after acute and chronic administration

The pharmacokinetics of zolpidem were studied after single dose, administered for either 7 or 28 days to rats. Thirty minutes after the last dose, animals were killed and the brain removed. The highest concentrations in plasma, which were observed at the first sampling time (0.5 h) were 2341 +/- 540 (day 0), 1956 +/- 325 (day 7) and 2908 +/- 1369 ng mL-1 (day 28). Corresponding AUC values of 1742 +/- 488, 1583 +/- 422 and 2683 +/- 1249 ng mL-1 h were found. MRT increased significantly from 0.46 +/- 0.06 h on day 0 to 0.67 +/- 0.02 h on day 28. The cerebral levels showed no significant change during the chronic administration (766 +/- 285, 685 +/- 171 and 887 +/- 264 ng g-1, respectively). No modification of the principal kinetic parameters was detected up to the 28th day of treatment.

Review of legal instruments and codes on medical experimentation with children

Medical research with children has been the subject of ongoing debate. The reason for controversy is clear. As with research on adults, one must strike a balance between two goals – promoting the health of children through advances in scientific knowledge and protecting child research subjects from exploitation and harm. However, because of their age and relative immaturity, children cannot protect their own interests as well as adult subjects can. Yet as they progress toward adulthood, increasing care must be taken to involve children in decisions that affect them, even to the extent of allowing them to make choices that may have serious and long-term consequences.

Midazolam daytime residual effect evaluated by the Multiple Sleep Latency Test

Daytime sleepiness after ingestion of midazolam as a hypnotic was quantitatively studied employing the Multiple Sleep Latency Test (MSLT). We evaluated 20 healthy volunteers, 10 of which received a single oral dose of midazolam (15 mg, one tablet) and 10 of which received placebo, in a double-blind design. Tablets were administered at 2200 h, bedtime. On the following day, all subjects were submitted to a clinical evaluation, a subjective checklist and the MSLT. The mean age was 34.7 +/- 8.9 years in the midazolam and 38.0 +/- 10.6 years in the placebo groups (n.s.). Sex and weight distributions were similar in both groups (n.s.). Clinical evaluation and subjective symptom checklist did not make evident significant differences between midazolam and placebo groups (n.s.). The MSLT was performed at 0900, 1100, 1300, 1500 and 1700 h. Mean sleep latencies were 12.0, 12.7, 8.0, 13.5, 17.0 min in the midazolam group; mean sleep latencies were 13.8, 9.0, 6.9, 9.5, 13.6 min in the placebo group (n.s.). In the single dose, double-blind design here evaluated, midazolam did not show differences in relation to placebo on the following day, detectable by the MSLT.

The safety and efficacy of zolpidem in insomniac patients: a long-term open study in general practice

The safety and efficacy of 10 or 20 mg/day zolpidem, a new hypnotic belonging to the imidazopyridine class, were studied over a 180-day period in 96 patients with sleep disorders. The treatment was continued for a further 180 days by 49 of these patients. Follow-up information from 21 patients who discontinued treatment after 180 days showed no rebound insomnia or withdrawal signs. Efficacy of treatment with respect to reduction of sleep onset latency and number of nocturnal wakenings, and improvement in duration of sleep, quality of sleep and morning wakenings was found in nearly 90% of patients and was maintained in those patients who continued treatment for 360 days. This efficacy was achieved with a stable percentage of patients receiving 10 mg/day and 20 mg/day zolpidem from day 30 to the final visit. Zolpidem, therefore, has been shown to be an effective and safe hypnotic, and to be devoid of rebound and withdrawal effects.

[Benefits and risks of hypnotics]

Rationalisation of the war of hypnotics has recently been under discussion in France: a review of the benefits and risks of these substances may therefore be useful. Chronic insomnia is a result of multiple factors, among which individual characteristics of the personality play an important role. Hypnotic treatment is symptomatic; its beneficial influence on sleep progressively vanishes in few weeks, while some negative residual effects on daytime functioning (mood, alertness, performance, memory impairment) may persist. The main problems posed by hypnotic treatment with benzodiazepines are related to tolerance effects during the treatment period and to rebound insomnia and withdrawal phenomena after discontinuation. Practical issues for the treatment of insomnia, based on international consensus, are presented.

Treatment of insomnia with two benzodiazepines: a double-blind crossover study

Twenty-eight patients (12 M, 16 F) with insomnia were treated with nitrazepam 5 mg/d and oxazepam 25 mg/d, each for 11 days, in a double-blind crossover comparison with placebo. Half the patients received nitrazepam in the first drug period, and oxazepam in the second and the other half followed the contrary sequence. Both nitrazepam and oxazepam were found to be effective in inducing sleep and increasing sleep quality. No effects on dreaming or adverse effects were found. Nitrazepam did influence the frequency of awakening, but only in the second drug period. In the first period it reduced self-waking. It is concluded that both nitrazepam and oxazepam were effective in inducing sleep and in improving sleep quality.

Long-term treatment of insomnia with zolpidem: a multicentre general practitioner study of 107 patients

The effects of zolpidem, an imidazopyridine derivative, were studied in 107 patients suffering from insomnia, 60.9% of whom were over 60 years of age, in a 6-month, single-blind, flexible dose, general practitioner study. Comparison was made between baseline, last day of treatment and 10 days after the end of treatment to assess efficacy and rebound insomnia. An improvement in all efficacy parameters--time taken to fall asleep, total amount of nocturnal sleep and number of nocturnal awakenings--was reported by the investigator and the patients; the improvement was evident from the first evaluation day and was maintained throughout the trial. Improvement was also maintained during the washout period with a lack of rebound insomnia. There was no sign of withdrawal symptoms and tolerance to zolpidem did not develop over the 6-month treatment period. Adverse events were mild and infrequent, and tended to resolve with a dose reduction. It is concluded that 10 mg/day zolpidem is an appropriate starting dose and is effective and safe for the treatment of sleep disturbances of different origins.

Repeated dose effects of lormetazepam and flurazepam upon driving performance

The residual effects of lormetazepam 1 mg and 2 mg in soft gelatine capsules on driving performance were assessed and compared to those of flurazepam 30 mg, which is also a powerful hypnotic, but possesses a far less favourable pharmacokinetic profile with a long-acting sedative metabolite. Driving performance was tested 10 to 11 h and 16 to 17 h post administration, after 2 days on placebo (baseline), and 2, 4 and 7 days of drug treatment (active), and after 1 and 3 days following the resumption of placebo (washout). The driving test consisted of operating an instrumented motor-vehicle over a 72 km highway circuit in light traffic. Flurazepam 30 mg significantly impaired the ability to control the lateral position of the vehicle compared to placebo baseline measurements. The degree of impairment was substantial in the female subjects and was greater in the morning than in the afternoon. Lormetazepam 1 mg showed no residual effect on driving performance. Lormetazepam 2 mg impaired driving performance to some extent on the following morning, 10 to 11 h post administration, but no residual effect was found in the afternoon. All drugs improved sleep quality and prolonged sleep duration to more or less the same extent.

Problems and pitfalls in the use of benzodiazepines in the elderly

Benzodiazepines are frequently prescribed for elderly patients living in the community and for those in hospitals and institutions. Their use is more prevalent in women. Prolonged use of benzodiazepines is particularly likely in old age for the treatment not only of insomnia and anxiety, but also of a wide range of nonspecific symptoms. Long term users are likely to have multiple concomitant physical and psychological health problems. The distinction between benzodiazepine anxiolytics and hypnotics is difficult and somewhat arbitrary, since the differences between the compounds are less than their similarities, especially in respect of adverse reactions. Despite their wide therapeutic range, elderly patients are particularly prone to adverse reactions to benzodiazepines. The incidence of unwanted effects, predominantly manifestations of central nervous system depression, has been found to be significantly increased in hospitalised elderly patients, particularly in the frail elderly. Studies on unwanted effects during long term use are scarce, but there is some evidence of tolerance to side effects. However, benzodiazepines have been found to be frequently implicated in drug-associated hospital admissions. There is suggestive evidence that benzodiazepines, especially compounds with long half-lives, may contribute to the falls which are a major health problem in old age. The incidence of benzodiazepine dependence in elderly patients is unknown. The features of benzodiazepine withdrawal in the elderly may differ from those seen in young patients; withdrawal symptoms include confusion and disorientation which often does not precipitate milder reactions such as anxiety, insomnia and perceptual changes. Problems due to both adverse reactions and to benzodiazepine withdrawal may easily be overlooked in multimorbid elderly patients, particularly in those suffering from disorders of the central nervous system. There are numerous studies on benzodiazepine pharmacokinetics indicating that alterations, especially in distribution and elimination of certain compounds, occur in old age. Benzodiazepines with oxidative metabolic pathways and longer half-lives are likely to accumulate with regular administration. However, changes in pharmacodynamics may be more important to explain altered responses to benzodiazepines in the elderly. Although information on pharmacodynamics is still limited, there is convincing evidence of increased pharmacodynamic response in the elderly which may be further accentuated by disease factors. Since the variability of pharmacological response increases with age and is not always predictable, there is good reason at least to start therapy at lower doses and to titrate dosages individually. This may also be appropriate for the newer benzodiazepines, irrespective of advantageous pharmacokinetics.(ABSTRACT TRUNCATED AT 400 WORDS)

Medication and skilled work

There is increasing interest in the way in which drugs impair performance. This has arisen because some may impair day-to-day skills of those whose occupations demand vigilance and motor skill, and of those who are involved in decision making or where interpersonal relations are crucial. For many years the position was adopted, at least in certain occupations where impaired performance could be a danger to others, that the use of any drug should preclude employment. However, recent advances in therapeutics and a greater understanding of drug action in man has made this rather uncomplicated view of life less tenable, and there is now an increasing desire that advances in therapy should, if at all possible, be available to occupational groups, such as airline pilots. In this way the adverse effect which a drug may have on performance has become an important aspect of its clinical profile. Hypnotics appropriate for transient insomnia, which may arise from the irregularity of rest inherent in many occupations, need to be free of residual effects, antihistamines that are sedative must be avoided, and drugs used in the management of mild hypertension, often during the important years of middle life, must be as free as possible from central effects. And it must be emphasized that these drugs are often used by active, healthy or near healthy individuals. The issues involved in the safe use of a particular drug by a particular individual are complex, and as with all aspects of therapeutics it is sometimes necessary to balance efficacy and adverse effects.

Quazepam. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic efficacy in insomnia

Quazepam is a trifluoroethyl benzodiazepine hypnotic with a half-life of 27 to 41 hours, which has been shown to induce and maintain sleep in the short to long term (up to 4 weeks) treatment of patients with chronic or transient insomnia. Although its hypnotic efficacy has been well characterised against placebo, there are few clinical studies in comparison with established hypnotics, particularly over long term administration. However, preliminary evidence suggests that quazepam 15 to 30 mg is as effective as flurazepam and triazolam in usual therapeutic doses, and causes minimal rebound insomnia following its withdrawal, unlike rapidly eliminated benzodiazepines such as triazolam. The lack of rebound phenomena is likely to be attributable to the 'carryover' effects occurring after discontinuation of quazepam, which has pharmacologically active metabolites with half-lives of elimination similar to or longer than that of the parent drug. Probably because of the long half-lives of quazepam's metabolites, daytime sedation, fatigue and lethargy are the most frequently reported side effects. These side effects are most intense with the 30 mg dose and least with the 7.5mg dose, which has not been studied extensively. Hence, quazepam is an effective hypnotic which may be particularly suitable for short or medium term use in patients in whom withdrawal effects or rebound insomnia may be especially bothersome. Further definition of certain characteristics of its profile--such as its long term use and potential for development of tolerance or dependence, effects on psychomotor skills, efficacy of the 7.5mg dose, and suitability in elderly patients and patients with chronic organic diseases--will assist in more clearly defining its ultimate place in therapy.

Patients, prescribing, and benzodiazepines

In order to establish the current status of benzodiazepine prescribing and also to assess patients' attitudes towards the use of these drugs, we interviewed 450 consecutive patients in 16 community pharmacies about their use of benzodiazepines. Prescribing rates increased ten-fold from the age of 20 to 70 years and were higher in women than in men. The average dose used in the elderly seemed excessive and the choice of hypnotic often inappropriate. The median duration of benzodiazepine use was 2.5 years (range 0-25) and 66% of the patients had been taking benzodiazepines for one year or more. Most of the patients (97%) found the drugs effective in the treatment of anxiety or insomnia. Twenty-two percent took a lower dose than prescribed and 7.5% a higher dose. These data suggest that benzodiazepines are prescribed for excessively long periods and that greater caution is needed in prescribing benzodiazepines for older patients.

A double-blind comparison of two lormetazepam doses in elderly insomniacs

The relative efficacy and tolerability of two lormetazepam doses, 0.5 mg and 1.0 mg, were compared in 145 elderly insomniacs in a double-blind, multi-centre study. On entry, data were recorded on the patient characteristics and sleep pattern, and patients were allocated at random to receive treatment with either 0.5 mg or 1.0 lormetazepam per night for 7 nights. Details were recorded daily in a diary by patients on sleep latency, the number of night-time awakenings, time of morning awakening, and whether they awoke refreshed. A record was also kept of any adverse effects of treatment. At the end of the study period, an overall assessment was made by the physician of the patients' response to treatment. The results showed that patients in both dose groups improved significantly (p = 0.001) in the three principal efficacy measures, but there were no apparent trends in the time when patients awakened in the morning. The only evidence of a difference in response to the two doses was that significantly (p less than 0.01) more patients on the larger dose were given a global rating of 'much improved' by the physician. Five patients withdrew from the study; 2 because of lack of efficacy, 2 because of side-effects, and 1 because of a suspected myocardial infarction not related to therapy. Only 6% of patients (4 on each dosage) reported adverse effects, most frequently related to carry-over sedation, i.e. drowsiness, sleepiness, muzzy head. (ABSTRACT TRUNCATED AT 250 WORDS)