Depression may be caused or aggravated by chronic benzodiazepine use, but is also a feature of the withdrawal syndrome. Depressive symptoms may appear for the first time after withdrawal, sometimes after a delay of a few weeks, and it can be severe and protracted for some months. It is not clear whether people who have had depression before, or have a family history of depression, are more prone to this complication, and its causes are not understood. As discussed in Chapters I and II, benzodiazepines disrupt the function of many neurotransmitters and hormones and depression could be the result, for example, of low serotonin activity combined with the stress of withdrawal. If severe enough to require definitive treatment, the depression in withdrawal responds to antidepressant drugs and/or cognitive therapy and usually diminishes gradually over 6-12 months. Insomnia

Severe depression may result from biochemical changes in the brain induced by benzodiazepines. Benzodiazepines are known to decrease the activity of serotonin and norepinephrine (noradrenaline), neurotransmitters believed to be closely involved in depression. Antidepressant drugs including the selective serotonin reuptake inhibitors (SSRIs such as Prozac) are thought to act by increasing the activity of such neurotransmitters. It has long been known that there is a wide variation between individuals in the rate at which they metabolise psychotropic drugs, including benzodiazepines, antidepressants and antipsychotics. People can be poor or slow metabolisers, normal metabolisers, or extensive metabolisers for these drugs, depending on the genetically determined activity of certain drug metabolising enzymes (CYP450 2D6 enzymes). In particular, there appear to be more poor and slow metabolisers among Asian patients than in European populations, according to an important US study. This means that Asian patients respond to lower doses and experience Readers may well ask: Why do we have specific benzodiazepine receptors in our brain? They have clearly not evolved over thousands and millions of years just to sit there and wait until Valium arrived! Most drugs that affect the brain act on receptors that are already there, and all of these drugs have subsequently been found to take the place of natural substances synthesised within the body. For example, the receptors for morphine react with natural endogenous endorphins and enkephalins, the physiological pain-killers; the receptors for cannabis are normally stimulated by natural substances called anandamides (named after the Sanskrit word ananda, which means "bliss"); nicotine in tobacco reacts with nicotine receptors for the natural neurotransmitter acetylcholine; all the psychotropic drugs like antidepressants and antipsychotics affect the receptor for natural neurotransmitters such as serotonin, noradrenaline and dopamine. The conclusion from such discoveries is that there must exist a natural benzodiazepine which normally modulates the activity of GABA at GABA/benzodiazepine receptors, like diazepam, and acts as an inborn, calming, sleep-inducing and anticonvulsant agent.As a consequence of the enhancement of GABA's inhibitory activity caused by benzodiazepines, the brain's output of excitatory neurotransmitters, including norepinephrine (noradrenaline), serotonin, acetyl choline and dopamine, is reduced. Such excitatory neurotransmitters are necessary for normal alertness, memory, muscle tone and co-ordination, emotional responses, endocrine gland secretions, heart rate and blood pressure control and a host of other functions, all of which may be impaired by benzodiazepines. Other benzodiazepine receptors, not linked to GABA, are present in the kidney, colon, blood cells and adrenal cortex and these may also be affected by some benzodiazepines. These direct and indirect actions are responsible for the well-known adverse effects of dosage with benzodiazepines. It cannot be too strongly stressed that withdrawal symptoms can be minimised and largely avoided by slow tapering, tailored to the individual’s needs as outlined in Chapter II. However, some long-term benzodiazepine users begin to experience “withdrawal” symptoms even though they continue taking the drug. This is due to the development of drug tolerance ( Chapter I) which sometimes leads doctors to increase the dosage or add another benzodiazepine. Analysis of the first 50 patients who attended my benzodiazepine withdrawal clinic showed that all of them had symptoms on first presentation while still on benzodiazepines (12 of them were taking two prescribed benzodiazepines at once). Their symptoms included the full range of psychological and physical symptoms usually described as benzodiazepine withdrawal symptoms. The process of slow benzodiazepine tapering in these patients caused only slight exacerbation of these symptoms, which then declined after withdrawal. Duration of effects. The speed of elimination of a benzodiazepine is obviously important in determining the duration of its effects. However, the duration of apparent action is usually considerably less than the half-life. With most benzodiazepines, noticeable effects usually wear off within a few hours. Nevertheless the drugs, as long as they are present, continue to exert subtle effects within the body. These effects may become apparent during continued use or may appear as withdrawal symptoms when dosage is reduced or the drug is stopped. Once started on an antidepressant for depression, the treatment should be continued for some months (usually about 6 months) to avoid recurrence of the depression. Benzodiazepine tapering can continue during this time, and the antidepressant will sometimes act as a welcome umbrella during the last stages of withdrawal. It is important to finish the benzodiazepine withdrawal before starting to withdraw the antidepressant. Quite often, people taking long-term benzodiazepines are already taking an antidepressant as well. In this case they should stay on the antidepressant until the benzodiazepine withdrawal is complete.

Fig. 1. Diagram of mechanism of action of the natural neurotransmitter GABA (gamma aminobutyric acid) and benzodiazepine on nerve cells (neurons) in the brain A minority of people who have withdrawn from benzodiazepines seem to suffer long-term effects – protracted symptoms that just don’t go away after months or even years. It has been estimated that perhaps 10-15 per cent of long-term benzodiazepine users develop a “post-withdrawal syndrome”. Many of these people have taken benzodiazepines for 20 years or more and/or have had bad experiences in withdrawal. The incidence of protracted symptoms in those who have undergone a slow taper under their own control is almost certainly very much lower. Table 3 shows the symptoms most likely to be long-lasting. These include anxiety, insomnia, depression, various sensory and motor symptoms, gastrointestinal disturbances, and poor memory and cognition. The reasons why these symptoms persist in some people are not clear. Probably many factors are involved, some directly due to the drug and some to indirect or secondary effects (See Table 4). TABLE 3. SOME PROTRACTED BENZODIAZEPINE WITHDRAWAL SYMPTOMS Symptoms The same principles apply to food. Humans are singularly well adapted through evolution to obtain the nutrients they need from a wide variety of diets and to eliminate unwanted products. A normal healthy diet which includes generous amounts of fruit and vegetables and a source of protein and fats (from meat or vegetables), and not too much pure sugar or “junk foods”, provides all the nutrients a person needs. There is no general need for dietary supplements or extra vitamins or minerals or for “detoxifying” measures. All these can be harmful in excess. Advice to cut out white flour, white sugar etc. may help certain individuals but I have also observed that overly restrictive diets can have adverse effects. Some people say they have felt much better after going on a particular diet – this makes one wonder what sort of diet they were eating before! One mechanism which might be involved in long-term (and possibly permanent) effects of benzodiazepines is an alteration in the activity of benzodiazepine receptors in brain GABA neurones. These receptors down-regulate (become fewer) as tolerance to benzodiazepines develop with chronic use. Such down-regulation is a homeostatic response of the body to the constant presence of the drugs. Since benzodiazepines themselves enhance the actions of GABA, extra benzodiazepine receptors are no longer needed, so many are, in effect, discarded. These down-regulated receptors are absorbed into neurones where, over time, they undergo various changes including alterations in gene expression. When these receptors are slowly reinstated after drug withdrawal, they may return in a slightly altered form. They may not be quite so efficient as before in increasing the actions of GABA, the natural 'calming' neurotransmitter. As a result, the brain may be generally less sensitive to GABA and the individual is left with heightened central nervous system excitability and increased sensitivity to stress. Molecular biologists point out that changes in gene expression can be very slow, or even unable, to reverse. (The action of benzodiazepines at GABA receptors is explained more fully in the Manual).

Discontinuing after short-term use

A controlled study of long-term benzodiazepine users using brain function techniques would have to be carefully designed and would involve a large number of age and sex matched subjects, probably over 100 in both control and user groups. In the benzodiazepine group it would have to take into account dose, type of benzodiazepine, duration of use, psychiatric history, symptoms, use of alcohol and other drugs, and a number of other factors. Such a study would be expensive and funding would be difficult to obtain. Drug companies would be unlikely to offer support, and to date 'independent' bodies such as the Medical Research Council, the Wellcome Foundation and the Department of Health have shown little interest. Thus the question of whether benzodiazepines cause brain or other organ damage remains unanswered. Return of SWS seems to take longer after withdrawal, probably because anxiety levels are high, the brain is overactive and it is hard to relax completely. Subjects may have difficulty in getting off to sleep and may experience “restless legs syndrome”, sudden muscle jerks (myoclonus) just as they are dropping off or be jolted suddenly by a hallucination of a loud bang (hypnagogic hallucination) which wakes them up again. These disturbances may also last for several weeks, sometimes months. These results have raised the question of whether benzodiazepines can cause structural brain damage. Like alcohol, benzodiazepines are fat soluble and are taken up by the fat-containing (lipid) membranes of brain cells. It has been suggested that their use over many years could cause physical changes such as shrinkage of the cerebral cortex, as has been shown in chronic alcoholics, and that such changes may be only partially reversible after withdrawal. However, despite several computed tomography (CT) scan studies, no signs of brain atrophy have been conclusively demonstrated in therapeutic dose users, and even the results in high dose abusers are inconclusive. It is possible that benzodiazepines can cause subtle changes which are not detected by present methods, but on the available evidence there is no reason to think that any such changes would be permanent. Gastrointestinal symptoms The number of people world-wide who are taking prescribed benzodiazepines is enormous. For example, in the US nearly 11 per cent of a large population surveyed in 1990 reported some benzodiazepine use the previous year. About 2 per cent of the adult population of the US (around 4 million people) appear to have used prescribed benzodiazepine hypnotics or tranquillisers regularly for 5 to 10 years or more. Similar figures apply in the UK, over most of Europe and in some Asian countries. A high proportion of these long-term users must be, at least to some degree, dependent. Exactly how many are dependent is not clear; it depends to some extent on how dependence is defined. However, many studies have shown that 50-100 per cent of long-term users have difficulty in stopping benzodiazepines because of withdrawal symptoms, which are described in Chapter III. Some people have no problems at all with their digestive systems during or after withdrawal, and may even notice that they are enjoying their food more. Others, perhaps more prone constitutionally, may complain of a range of symptoms associated with “irritable bowel syndrome” (IBS). These can include nausea, vomiting, diarrhoea, constipation, abdominal pain, flatulence, gaseous distension and heartburn. Quite a few have found these symptoms so uncomfortable that they have undergone hospital gastrointestinal investigations, but usually no abnormality is found. The symptoms may be partly due to overactivity in the autonomic nervous system, which controls the motility and secretions of the gut and is very reactive to stress, including the stress of benzodiazepine withdrawal. In addition, there are benzodiazepine receptors in the gut. It is not clear what the functions of these receptors are or how they are affected by benzodiazepines or benzodiazepine withdrawal, but alterations in these receptors may play some part in increasing gut irritability.

Tolerance is a phenomenon that develops with many chronically used drugs (including alcohol, heroin and morphine and cannabis). The body responds to the continued presence of the drug with a series of adjustments that tend to overcome the drug effects. In the case of benzodiazepines, compensatory changes occur in the GABA and benzodiazepine receptors which become less responsive, so that the inhibitory actions of GABA and benzodiazepines are decreased. At the same time there are changes in the secondary systems controlled by GABA so that the activity of excitatory neurotransmitters tends to be restored. Tolerance to different effects of benzodiazepines may vary between individuals - probably as a result of differences in intrinsic neurological and chemical make-up which are reflected in personality characteristics and susceptibility to stress. The development of tolerance is one of the reasons people become dependent on benzodiazepines, and also sets the scene for the withdrawal syndrome, described in the next chapter. T he benzodiazepine withdrawal symptom that raises most fear of going mad is hallucination. Terrifying hallucinations have occurred in people undergoing rapid or abrupt withdrawal from high doses, but the reader can be reassured that they are exceedingly rare with slow dosage tapering as outlined in Chapter II. If hallucinations occur, they are usually visual – patients have described hallucinations of a large bat sitting on the shoulder, or the appearance of horns sprouting from a human head – but auditory, olfactory and tactile hallucinations can also occur. Somewhat less frightening are hallucinations of small creatures, usually insects, which may be associated with the sensations of insects crawling on the skin (similar hallucinations occur in cocaine and amphetamine withdrawal). Sometimes hallucinations merge with illusions and misperceptions. For example, a coat hanging on the door may give the illusion of being a person. Floors apparently tilting and walls that seem to slope inwards are perceptual distortions. One reassuring finding from many clinical studies is that eventual success in withdrawal is not affected by duration of use, dosage or type of benzodiazepine, rate of withdrawal, severity of symptoms, psychiatric diagnosis, or previous attempts at withdrawal. Thus from almost any starting point, the motivated long-term user can proceed in good heart. PROTRACTED WITHDRAWAL SYMPTOMS Regular moderate exercise is recommended during withdrawal as it maintains general fitness, builds up stamina, increases the circulation to brain, muscle and skin and improves mood, but there is no point in slavishly doing exercises that you hate. The aim is to lead a healthy lifestyle which by definition includes some exercise in a form that is enjoyable for you. Smoking Sensory symptoms: tinnitus, tingling, numbness, deep or burning pain in limbs, feeling of inner trembling or vibration, strange skin sensationsBenzodiazepines are potent anticonvulsants. They can be life-saving in status epilepticus (repeated fits, one after another) and in fits caused by overdose of certain drugs (for example, tricyclic antidepressants). However, rapid withdrawal, especially from high potency benzodiazepines, can precipitate epileptic fits as a rebound reaction. Such an occurrence is extremely rare with slowly eliminated benzodiazepines (e.g. diazepam) or with slow dosage tapering. If a fit does occur in these circumstances, it is usually only a single fit and causes no lasting damage. Other phenomena seen in rapid withdrawal are psychotic symptoms, severe confusion and delirium, but again these hardly ever occur with slow dosage tapering. By following the withdrawal schedules outlined in Chapter II, you can be confident of avoiding these complications. EXTRA MEDICATION DURING BENZODIAZEPINE WITHDRAWAL Teaches patients to understand their thinking patterns so that they can react differently to anxiety-provoking situations