Addiction Treatment Blog

To attempt to write an impartial account of the benzodiazepines is all but impossible (1,2). When they were first introduced these drugs (see the table below) were seen as being of major benefit, and they were widely regarded as extremely safe and demonstrably effective. They were popular with both physicians, consumers and the pharmaceutical industry. Indeed, they appeared to be so effective and so effective and so popular they have caused serious problems for the development and marketing of any new anxiolytic.

More recently, the benzodiazepines have been described as the greatest menace in peace time. They have been seen as the epitome of the psychotropic drug juggernaut, whose prescription must be curbed at all costs. There has been a variety of TV and radio programmes highlighting their dangers and the horrors of dependence, and it has been claimed that coming off them is harder than coming off heroin. But strangely enough, benzodiazepine dependence is perhaps the only case of drug dependence in which the dependent person is viewed with sympathy. He is portrayed as a victim of forces beyond his control, rather than as author of his own destiny (3). One possibility that this suggests is that consumers have taken up arms against the medicopharmaceutical complex rather than simply against the dangers of this particular group of drugs.

The other half of the argument, which is still put forward by medical practitioners and the pharmaceutical industry, is that these drugs remain remarkably safe, that reports of dependence and withdrawal reactions are exaggerated and that withdrawal phenomena are probably more linked to the personality of the sufferer than to the pharmacology of the drugs.

These opposing views have become so polarised over the years that it is very difficult to write an account of benzodiazepines that will not alienate someone. The position taken here will be that the benzodiazepines are far safer for most people than they are currently perceived to be, but that there is a sub-group of individuals, who through no fault of their own, will encounter serious difficulties with them. Also, I believe, the benzodiazepines have provided something of a stick to beat the pharmaceutical industry with – in some respects, perhaps, the wrong stick, but the choosing of these things result from a combination of accidental factors interacting with the spirit of the times.

It is appropriate, therefore, to review the history of the benzodiazepines before outlining the various compounds, with their benefits and side effects. The first benzodiazepines came on the market in 1960, when the available alternatives were the barbiturates or neuroleptics. There were serious drawbacks to the barbiturates: excessive sedation, a high risk of dependence and substantial fatalities in overdose. The neuroleptics, while not afflicted with these problems, have their own drawbacks (see Side Effects of Neuroleptics) and their prescription was seen as inappropriate for milder or neurotic disorders.

It was into this situation that the benzodiazepines were introduced. They had none of the side effects of neuroleptics and, compared to the barbiturates, they appeared to produce a relatively mild sedation, to be free of the risk of physical dependence and most of all to be very safe in overdose. They became increasingly popular and widely prescribed.

We now recoil from what happened during the 1960s and 1970s. There is evidence that many patients do as well with brief counselling from general practitioners as they do on benzodiazepines, and that they are as happy with such counselling. General practitioners, today, often squirm with guilt in the face of such findings. But it should be mentioned that before the large scale prescription of benzodiazepines there was a great deal of chemical management of neurotic and anxiety disorders. Before the mid-1960s this involved the use of barbiturates and a significant number of deaths resulted.

Furthermore, the chemical tranquillisation of anxiety appears to be something that both the medical profession and we, the drug takers, have engaged in even prior to the establishment of the modern pharmaceutical industry. In the last century, opium was used widely in a variety of preparations which were bought in large quantities over the counter. Demand was, in this instance, clearly consumer led. Hence it may be somewhat naive to ascribe the dark side of the benzodiazepine story solely to the pharmaceutical industry following the siren call of the profit motive oblivious and greater good.

Quite apart from barbiturates and opiates, it should also be pointed out that human beings have relied extensively on alcohol for millennia to tranquillise anxiety and provide sedation. By any standards, alcohol must be seen as a far more dangerous compound than the benzodiazepines and yet society’s concern regarding it seems much less than its anxiety about the benzodiazepines.

Table of Contents

• Mechanism of action of benzodiazepines
  • The classification of benzodiazepines by half-life
• Classes of benzodiazepines
• Indications for benzodiazepines
• Anxiolysis
• Anticonvulsant
• Sedation
• Muscle Relaxant
• Amnesia
• Abreaction
• Alcohol withdrawal
• Rapid tranquillisation
• Side effects
  • Sedation
  • Rebound anxiety
  • Amnesia
  • Dissociation
  • Benzodiazepine dependence and withdrawal
    • Symptoms of benzodiazepine withdrawal
  • Benzodiazepines and driving
• References
• Help

Mechanism of Action of Benzodiazepines

We know almost as much about how benzodiazepines work as we do about neuroleptics. In both instances we know far more than we know about how the antidepressants work. Attempts to unravel the mechanism of action of benzodiazepines have, furthermore, in recent years led to significant advances in the science of psychopharmacology generally.

The first development in our understanding of the benzodiazepines came with the discovery that a compound called gamma-aminobutyric acid (GABA) is the most plentiful neurotransmitter in the brain, and the brain’s principal inhibitory neurotransmitter. Benzodiazepines bind to and modulate GABA receptors. They neither block messages through GABA system or create artificial messages, but rather modulate normal functioning. There are three types of benzodiazepine (BZ) receptor, BZ-1, BZ-2 and BZ-3, mediating sedative, myorelaxant and anxiolytic effects respectively.

It has emerged that there are a number of natural compounds within the brain that bind to the same sits on the GABA receptor as the benzodiazepines. The implication of this is that there are a set of natural compounds in the brain performing much the same function that benzodiazepines perform, the best candidates for which seem at present to be a group of compounds called the beta-carbolines.

One surprising finding has been that beta-carbolines may both alleviate anxiety and cause relaxation just as benzodiazepines do, but also that other beta-carbolines may cause anxiety, tension and convulsions. This finding has led to significant changes in our understanding of how neurotransmitters and receptors work naturally.

It has previously been thought that neurotransmitters act on receptors that drugs may either mimic this action or antagonise it. It now seems clear that different compounds within the brain may produce opposite actions the same receptor site. Where the benzodiazepine receptors are concerned, we now appear able to produce compounds that relieve anxiety, compounds that increase anxiety and compounds that block both of these effects. These three types of compound differ, but all act at the same receptor site.

Another interesting feature of the benzodiazepines is that the benzodiazepine receptor appears only to have evolved in higher animals. The other neurotransmitters that have been discussed in this blog such as noradrenaline, dopamine and 5-HT are all found in single celled and simple organisms. Benzodiazepine receptors in contrast are confined mostly to cortical areas of the brain and have only emerged in relatively speaking higher animals – they also occur naturally in certain plant species.

Classes of benzodiazepines

By convention, the benzodiazepines are divided up according to the length of time it takes for the amount of the drug in the blood to decrease to half its initial level after a standard dose – their half-life (see the table above). There was a great deal of interest in this concept during the late 1960s and early 1970s, as it was thought that producing a benzodiazepine with a short half-life might overcome a number of problems that were then apparent with some of the earlier compounds, such as diazepam. The half-life of some of these was so long that taking the pills regularly meant that a first pill had not washed out of the system by the time a second was taken and so on. This led to a steady accumulation of the drug, which in the elderly was a particular problem. However, even in the case of the supposedly shorter-acting compounds, it should be kept in mind that while the duration of action depends on the chemical make-up of the compound, it also depends on how much of the drug is given – a large amount of a short acting compound may act for a long time.

Indications for benzodiazepines

Benzodiazepines give a relaxing warm glow, not unlike alcohol. There is a sense of muscular release and a soothing feeling that most people who take them describe as being positively pleasant. In one sense they are one of the twentieth century’s greatest inventions. After perhaps up to 2000 years of trying to improve on alcohol, they represent success. They can be used for the same purposes as alcohol – for general relaxation purposes, as anti-anxiety agents for acute crises such as interviews or whatever, and they are just generally pleasant in the way alcohol is. Furthermore, they are free of many of the drawbacks of alcohol; they do not cause liver, heart, joint and gut problems and the generalised brain cell loss that alcohol causes. They do not cause weight gain or vomiting after excess; they are much cheaper than alcohol and above all are much safer in overdose than alcohol.

Anxiolysis

To say that benzodiazepines are anxiolytic seems rather superfluous. They are, but as the previous articles on the management of anxiety (see Occasions of Anxiety) suggests they are by no means universally anxiolytic. They are of benefit when the anxiety state has a significant muscular tension or dissociative component to it. The anxiolytic effect of benzodiazepines appears to resemble most the effects of alcohol. The way they are used also supports this contention. This anxiolysis differs clearly from the ‘anxiolytic’ effect of neuroleptics. Neuroleptic tranquillisation works best in distraught and agitated rather than in anxious states. Benzodiazepine anxiolysis also differs from the anxiolysis brought about by beta-blockers, whick work best in states characterised by increased heart rate, palpitations, butterflies in the stomach and other shakes of the hand. At present it seems that compounds acting on the 5-HT system are likely to have an anxiolytic effect that more resembles that produced by neuroleptics.

The above description of the anxiolytic effects of benzodiazepines is only approximate. Greater precision is not possible at present, which seems remarkable seeing that so many benzodiazepines have been prescribed and taken in the past 30 years. One might expect that there would be a better appreciation of just what kind of anxiolysis they bring about.

Anticonvulsant

Benzodiazepines are generally anticonvulsant. They are not used widely for epilepsy because the barbiturates, phenytoin and carbamazepine are more effective. In states of intractable epilepsy, however, the benzodiazepines may often be used in conjunction with these other compounds. One in particular, clobazam, is used more widely in epilepsy as it provides the anticonvulsant effects of a benzodiazepine without producing the associated sedation. In cases of status epilepticus, intravenous diazepam is the drug of first choice. Another benzodiazepine, clonazepam, is also used for the management of epilepsy, restless leg syndrome, myoclonic jerks and a range of other neuropsychiatric indications.

Sedation

Benzodiazepines are sedatives in much the same way as barbiturates and alcohol, although they are somewhat less sedative than barbiturates and somewhat more than alcohol. The sedation produced, however, varies from person to person and from benzodiazepine to benzodiazepine. With regular ingestion of benzodiazepines, tolerance to these sedative effects develops quickly. In addition, there is little or no sedation associated with clobazam. The sedative effects of benzodiazepines provide the basis for their use as hypnotics. Although the use of benzodiazepines as anxiolytics has decreased markedly in the last 10 years, their use as hypnotics has not, and they are prescribed for sleeping purposes as regularly now as before.

Muscle Relaxant

Benzodiazepines are also effective muscle relaxants and are used for this purpose in spasticity, dystonia and multiple sclerosis. A proportion of their anxiolytic effect may stem from this action, although there also appears to be an independent central anxiolytic effect.

Amnesia

The benzodiazepines can produce an amnesia that is quite like what happens with alcohol. Essentially, they impair the registration and subsequent recall of events that take place after they have been taken. This seems most marked for short-acting agents such as lorazepam, midazolam and triazolam. It is also more marked when the drugs are given intravenously. For this reason, short-acting benzodiazepines are given pre-operatively in order to produce amnesia regarding the events of surgery. Something like this effect may also be in part responsible for the complaints of people who have taken benzodiazepines for years, often during the years their children were growing up, that the past seems indistinct, hazy or blotted out to some extent.

The effects of benzodiazepines on memory are at present the subject of much investigation, as they provide a window on the study of memory do so by being stimulants of some sort, whereas drugs that sedate generally impair memory. This appeared to apply to the benzodiazepines, until it became clear that many, particularly when they enter the brain quickly, as after intravenous injection, produce striking memory deficits for periods after the sedative effects have worn off. Another odd thing about these findings was that amnesia was being produced less by the action of a drug on some receptor but rather as a consequence of the rate of binding to the receptor.

Abreaction

Paradoxically, the benzodiazepines may also be used for abreaction. Abreaction is a technique used to recover buried memories – often following trauma. It involves getting individuals to remember scenes from their past life in great detail. In the course of such remembering, it is hoped that hints about glimpses of the significant event or trauma will be recovered (4). Abreaction can be conducted without pharmacological intervention of any sort, but commonly the relaxation produced by a tranquilliser helps, and the mystique introduced into the process by hints that remembering is being assisted by a truth drug. A simplistic rationale is that relaxation permits memories, which are suppressed, to re-emerge into consciousness.

This rationale is obviously simplistic given that these drugs are, if anything, amnestic rather than memory enhancing. A partial reconciliation of the amnestic effects of benzodiazepines and barbiturates, and their role in bringing back buried memories, lies in the fact that the amnesia induced by these compounds is for events that happen after they are taken rather than for events that may have happened in the past. It is, for example, reasonable to work for an oral examination for weeks and then take a benzodiazepine the night before or morning of the oral without the homework done being wiped out. What is more likely to happen is that memory for the actual oral exam itself may be hazy but performance should not be affected.

Alcohol Withdrawal

The benzodiazepines are of significant benefit in states of alcohol withdrawal. Diazepam, chlordiazepoxide and chlormethiazole are the standard treatments used for people physically dependent on alcohol and who wish to discontinue. The early institution of a comprehensive benzodiazepine regime for such individuals all but abolishes the rigours of alcohol withdrawal and permits individuals to stop alcohol intake abruptly. The benzodiazepines can then be tailed off over the course of a week or two.

Rapid Tranquillisation

Concern has developed in recent years about deaths that have occurred during the course of the rapid tranquillisation (RT) of disturbed or violent behaviour. The intramuscular use of agents such as chlorpromazine have been particularly responsible. The concerns, however, prompted a fresh look at regimes for RT and a consensus is emerging that benzodiazepines have a place. The agent most commonly used at present would seem to be lorazepam (0.5-2.0 mg) because of its short duration of action and lower likelihood to accumulate. It can also be given orally, or by IM or IV routes, in contrast to diazepam which cannot be given IM. Emerging regimes involve the use of lorazepam alone, or in combination with haloperidol or droperidol (5 – see The Neuroleptics).

The primary hazard in the use of benzodiazepines for rapid tranquillisation is respiratory depression. If this occurs, it can be reversed by flumazemil (Anexate) which can be given continuously (200 µg – 600 mg IV) or administered in a glucose or saline solution.

Side Effects

Sedation

As mentioned sedation is a feature of benzodiazepines. This may be put to use for hypnotic purposes, however it can also impair normal daily functioning. It was to avoid such effects that the intermediate and short-acting benzodiazepines were synthesised. The impairment of daily functioning that can occur with tranquillisers such as diazepam, or sleeping pills such as nitrazepam, are comparable to the effects produced by alcohol. These compounds also impair reflex reactions and car-handling. Surprisingly, however, given concerns with alcohol and driving, there are no legal proscriptions against driving under the influence of benzodiazepines (see below).

The sedative effects of benzodiazepines depend heavily on the state of arousal of the individual concerned. For a subject who has never had benzodiazepines before, 5-10 mg of diazepam may be heavily sedating. For an individual who has had a modest amount of benzodiazepines in the past, taking 5 – 10 mg of diazepam may produce a noticeable but not undue sedative effect. The same individual going to have a tooth extraction, do an interview or engage in some anxiety provoking procedure may be able to take 30-40 mg just immediately prior to their ordeal without significant sedative effects. Up to 100 mg of diazepam may be necessary in some agitated states to produce noticeable sedation.

Rebound Anxiety

In some cases, benzodiazepine intake may cause as much anxiety as it alleviates. This effect is similar to an effect produced by alcohol. Individuals with marked anxiety problems, such as phobias, often turn to alcohol to help them cope with situations they know will provoke anxiety. While it may help in the short term, becoming alcohol dependent leads to withdrawal anxiety as the alcohol wears off. Similarly, intake, particularly of the shorter-acting benzodiazepines, may lead in susceptible individuals to an early development of withdrawal-based or rebound anxiety.

Amnesia

The amnestic effects of benzodiazepines have been the basis for many complaints regarding their use. Individuals who had been on these compounds for 10 or 20 years have subsequently claimed that they brought up their children while on these drugs but that all they can recall of a time they would now like to be able to remember is a haze. As mentioned above, the amnestic effects of benzodiazepines may be put to good use as pre-operative medications, and also they’ve been put to use for situations that don’t involve anaesthesia such as dental procedures or endoscopy or other procedures which involve the passage of tubes or instruments into the body for investigative purposes.

Concerns surrounding procedures such as these first led to a clear recognition of the amnestic effects of benzodiazepines. It was claimed by patients undergoing dental procedures and endoscopy that they had been taken advantage of, and the investigation of these claims led to the recognition of the amnesiac effects of benzodiazepines. It was claimed by patients undergoing dental procedures such as these first led to the recognition of a complicated picture. There was usually a clear relationship between events that had occurred and the complaint made. For example, in the case of dental procedures and endoscopy it was claimed that oral sex had taken place. In these instances what had happened was that instruments were put into the mouth. Similarly, in a procedure involving an individual having to squeeze a hand in order to pump up their vein prior to a blood sample being taken, it was claimed that the patient had been forced to masturbate the other person. In some cases, accusations have been upheld, in others the judgement has been that the drowsy state the subject was in made them more suggestible.

Ordinarily, the amnestic effects of benzodiazepines are not noticed. Every so often, however, people taking benzodiazepines find that something dramatic happens. For example, a colleague of mine after flying home from abroad and taking a short-acting benzodiazepine on the flight to promote sleep, went to his parents’ house immediately after getting off the plane. He met his sister in the drive and talked with her at length before going into his parents. The following day when he met her again he had no recollection of their encounter the previous day.

The benzodiazepines produce an anterograde amnesia. That is events that occur after taking them may not be registered fully. This effect is similar to the anterograde amnesia produced by anticholinergic compounds and by alcohol. Benzodiazepines may interact with both the anticholinergics and alcohol to make amnesia even more likely. The effects seem comparable in many respects to the blackouts that some people have on alcohol, which can occur after having had only one or two units of alcohol. Conversations have taken place after this modest amount of alcohol may not be recalled the next day.

Dissociation

Occasionally the benzodiazepines may produce dissociative reactions. The most commonly described reactions are states of hyperactivity. It is often thought that these involve disinhibition, that the benzodiazepines have inhibited some inhibitory pathway on the brain. This seems unlikely. What seems more likely is that just as alcohol may in certain individuals produce quite marked dissociative reactions,s characterised by profound amnesia and explosive behaviour following the intake of sometimes less than a pint of beer, so also the benzodiazepines in certain individuals who are particularly sensitive to their effects may produce markedly excitable and overactive or explosive behaviour (see section on dissociation in Side Effects of Antidepressants). Benzodiazepines have also been reported to produce depersonalisation, derealization and hallucinatory experiences. The frequency of these is unknown.

Benzodiazepine Dependence and Withdrawal

There were some early reports in Scandinavia from the mid-1960s of a possible physical dependence on benzodiazepines. These appear not to have become widely known, but it is their existence that underpinned legal action against drug companies, as there was some basis for the claim that the possibility of dependence was clear for almost 20 years before either companies or the medical profession began to take it seriously. The clear recognition of a physical dependence syndrome only occurred in the late 1970s or early 1980s, since when reactions to the dependence liability of benzodiazepines have been extreme on both sides of the argument.

It would seem, on the face of things, that the dependence potential of the benzodiazepines cannot be as serious as it is often now claimed to be, if so many people could have been prescribed so much of these drugs over the course of 20 years and not had significant problems. While there do appear to be significant number of problems. While there do appear to be a significant number of people who are having problems with withdrawal from benzodiazepines, these are only a small proportion of the overall numbers of people who’ve had benzodiazepines.

On the other hand, the medical response to this issue has been to write-off the sufferers from supposed dependence syndromes as individuals who of the initial anxiety, which their benzodiazepines had suppressed successfully for a considerable period of time. This recourse to personality is unwarranted given the current state of the evidence. It fans the flames of conflict and it may forestall a more serious attempt to get at the facts. The recent developments in our understanding of how benzodiazepines work, outlined above, are beginning to shed some light on the question of why some individuals develop problems on these drugs. The nature of the benzodiazepine receptor and the dual action of endogenous compounds, such as the beta-carbolines on it, opens up the possibility that one cause of problems following benzodiazepines may be that the receptors on which they work have been blocked for so long by these compounds that they become hypersensitive to the effects of the natural compounds in the brain that cause anxiety, insomnia, muscular tension and convulsions. Discontinuing drug treatment then leaves a hypersensitive receptor being bombarded by anxiogenic compounds.

This appears however not to be the whole story. The degree to which the benzodiazepine receptors shift to a state of being sensitive to the natural compounds acting to produce anxiety in the brain, is almost certainly genetically determined. There will therefore be a range of liabilities to shift. This range, in turn, likely to cause some people to become more sensitive to withdrawal of these compounds and to become sensitive at a quicker rate than others. Experimental findings and clinical experience bear this out.

If a given population are given the same benzodiazepine for the same period of time, different people show differential rates at which rebound anxiety and rebound insomnia develop. It is almost certainly the case, therefore, that quite apart from personality, there will be a physiological propensity to having difficulties with benzodiazepines. Current research suggests that about 1/4-1/5 of us are at risk of having marked sensitivity to benzodiazepine withdrawal.

The corollary of this is that, for the remaining 3/4 of us, benzodiazepines are far safer than current alarms would suggest and, indeed, for a proportion of us there may be quite minimal to insignificant risks associate with taking them, unless very large amounts are taken chronically.

Apart from physiological factors in the taking of benzodiazepines, there appear to be pharmacological factors to do with the drugs themselves that may produce sensitivity to withdrawal. Increasingly, it appears that benzodiazepine compounds which have a short half-life and which enter the brain rapidly are more likely to produce marked effects on withdrawal. Such compounds include alprazolam and lorazepam. The irony here is that the short acting compounds were produced in the first instance in order to avoid the prolonged sedaction that may be associated with benzodiazepines with a longer half-life such as diazepam or chlordiazepoxide. Thus, there are good grounds for suggesting that while personality may be a factor in benzodiazepine dependence, there are also significant physiological and pharmacological inputs to dependence, independent of the personality of the individual.

Symptoms of benzodiazepine withdrawal

The following have all been claimed as features of the withdrawal syndrome associated with benzodiazepines and equally, for the most part, dismissed by septical medical practitioners as manifestations of a recrudescence of anxiety:

• Increased anxiety with all its physical symptoms.
• Poor sleep.
• Unsteady gait.
• Numbness.
• Muscle pains.
• Feeling of things moving, as though on a boat.
• Aggressive feelings.
• Depression.
• Weakness and tiredness.
• Flu-like symptoms.
• Hallucinations.
• Paranoid ideas.
• Seizures.
• Confusional state.
• Depersonalisation or derealization.
• Craving.
• Restlessness.
• Nausea, abnormal taste and gastrointestinal cramps..

Withdrawal is more likely if a person is taking a high dose of a short-acting benzodiazepine that is tapered abruptly. It also seems somewhat more likely if the individual was highly anxious before being put on benzodiazepines and if they have a previous history of neurosis, although this latter is controversial. Current recommendations are that an individual should consider themselves hooked or at serious risk, if they cannot stop benzodiazepines for 2-3 days, whenever called upon to do so.

At present, it is also recommended that benzodiazepines should not be prescribed for longer than 4 weeks. After that, prescribers should review the issues rather than simply repeat the prescription. Doctors are now prescribing these drugs rather infrequently, if at all, as a first-line treatment for anxiety and most prescriptions are being issued to individuals who have been long-term takers.

Along with recent horror stories of medical negligence in creating physical dependence have gone a set of stories, less widely publicised, of doctors who, reacting with therapeutic Calvinism to the current climate, have withdrawn all benzodiazepines from all their patients regardless. This is often highly inappropriate, particularly in the case of individuals of 60 and upwards who have been on drugs for 10 years or more with little or no ill-effect.

Where withdrawal is undertaken, there is a recognised strategy for management. If individuals have difficulty in withdrawing from short-acting benzodiazepines, they should be switched to a long half-life compound, such as diazepam, as this is likely to give rise to rebound phenomena. Using the long half-life strategy, the usual regime is to taper over 6 weeks or so, reducing 1/4 of the dose in the first week, 1/4 in the second, and 1/8 in each of the subsequent 4 weeks. The last dose level or two may beet to be drawn out longer in some cases.

There have been attempts to find some compound that would attenuate benzodiazepine withdrawal, although none seems particularly effective to date. Clonidine, carbamazepine, antidepressants and beta-blockers have been used but with no convincing effects. A benzodiazepine antagonist, flumazenil, has recently been introduced clinically, although its use is restricted to anaesthetic practice at the moment. There are suggestions that this compound can both push individuals into withdrawal but also dramatically shorten the length of time withdrawal is liable to last.

There is some dispute as to how long the withdrawal syndrome lasts in those most severely affected. For most individuals, it appears to be effectively over in a matter of weeks, but for some there have been claims of symptoms recurring for months, or up to a year.

Benzodiazepines and driving

Psychiatric illnesses of all sorts slightly increase the risks of road traffic accident (RTA).

However, this includes the effects of dementia; at present it is not possible to calculate the mean effect of any one illness, such as anxiety or depression. Neither has work been done to differentiate between the RTAs stemming from untreated illness and those that stem from individuals on treatment. It would seem highly likely that antidepressants, particularly tricyclics and benzodiazepines, or other agents with sedative properties, may also contribute to RTAs, although the risks posed by such agents are much less than those posed by alcohol.

Section 4 of the Road Traffic Act (1998) makes it criminal offence for a person to drive under the influence of drugs, prescribed or otherwise. Present recommendations from the Royal College of Psychiatrists suggest that driving licenses should not be issued to or renewed for individuals who regularly take psychotropic regimes that would hamper their ability to drive safely (6). There are a number of problems here, one of which is that fact that there can be considerable variability in terms of how disabling a compound or regime may be. Another concerns the locus of responsibility should an accident happen. At present, the climate is shaping up that mental health professionals are probably best advised to warn subjects taking benzodiazepines, other sedatives or antidepressants, of the potential risks and of the need for them to avoid driving if they are experiencing difficulties, and to record that they have issued such advice. In the case of individuals who drive large goods or passenger carrying vehicles, the problems are clearly of a much more serious order and merit careful consideration. This is one of those situations where in certain circumstances the professional duties of confidentiality may be outweighed by other considerations, and it may be necessary to report an individual to the appropriate driving license authority.

References

1. Hindmarch I, Beaumont G, Brandon S, Leonard BE: Benzodiazepines: current concepts. Chichester: J Wiley and Sons; 1990.
2. Wheatley D: The anxiolytic jungle: where next? Chichester; John Wiley and Sons; 1990.
3. Bury M, Gabe J: A sociological view of tranquilliser dependence: challenges and responses. In Benzodiazepines: current concepts. Edited by Hindmarch I, Beaumont G, Brandon S, Leonard BE. Chichester: J Wiley and Sons; 1990:211-226.
4. Healy D: Images of trauma: from hysteria to post-traumatic stress disorder. London: Faber and Faber; 1993.
5. Pilowsky L, Ring H, Shine PJ, Battersby M, Lader M: Rapid tranquillisation. Br J Psychiatry 1992, 160:831-832.
6. Royal College of Psychiatrists: Psychiatric standards of fitness to drive large goods vehicles and passenger carrying vehicles. Psychiatr Bull 1993, 17:631-632.