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| The
Biological Basis of Depression
To understand antidepressant medication, you need to know a little about what happens in the brain when we are depressed. This section explains; Within this section of the web site we will look briefly and very generally at the medication used in the treatment of depression. Before we deal with that it is perhaps important to understand something more about the biological basis of depression. When we are depressed, physical changes
take place within our bodies. The most important of these take place
within the brain. It is on this basis that depression is considered a
physical illness, rather than merely something psychological or something
that exists only in the imagination or perception of the sufferer. It is
perhaps important to remember this if you, or someone you know, is
diagnosed as having depression. Remember, one cannot simply think oneself
out of it! There are real and tangible changes taking place in the
physiology of someone suffering from clinical depression. Back
to Top The Brain, Neurons and Synapses There are something like 10,000 million cells in your brain. Each of the cells has connections to other cells. It is thought that each brain cell may have as many as 25,000 connections to neighbouring cells. Of course, although each cell has the potential to be connected, in practice, these connections are not happening constantly. When connection is made, it is in the form of an electrical impulse which travels down the connections between cells (neurons) at a speed of about 120 mph. This process happens every time we think a thought or decide to move a muscle. It also happens every time something automatic and unconscious happens, for example, breathing air in and out, digesting a meal or releasing a hormone. The neurons that carry these electrical impulses contain small gaps called synapses. These are important because they allow electrical activity, and hence brain functioning, to be mediated (or controlled). In order for an impulse (or message) to jump from one neuron across the synapse to another, a number of important enzymes, called neurotransmitters, have to come into play. In total there six different groups of neurotransmitters and each one is specific to a particular type of brain cell. From the point of view of depression, the main neurotransmitters are serotonin (sometimes called 5HT or 5 hydroxytryptamine) and noradrenaline (sometimes called norepinephrine). It is known that people suffering from depression have low levels of these two neurotransmitters and this is thought to lead to the main symptoms of low mood, low-energy, depressed outlook, disturbed sleep and low drive or arousal. Again, it is worth emphasising that
although depression is "in your head" it has very real physical
consequences and these are not merely imagined -- they arise out of
distinct chemical changes in the brain. Back
to Top Is Depression Purely About Your Biology? Because we know that depression is associated with low levels of certain important neurotransmitters, this has led to speculation about the causes of depression. For a time, many doctors believed that depression arose as a consequence of deficiencies in levels of certain of these brain chemicals. In this view, depression might be little more than a physical illness. So, just as diabetes is a disease caused by insufficient insulin production, so might depression be a disease caused by insufficient production of serotonin or noradrenaline. Such a perspective would have consequences in terms of the potential for us to effectively "inherit" depression, in as much as the characteristic (or "depression gene") might be passed down in families. There was certainly some evidence for this view -- we know, for example, that having a parent who suffers from depression can make it more likely that you also will suffer from depression. However, most neuroscientists now believe that such a view offers us only a partial understanding of the mechanisms of depression. Recent advances in neuroscience have been able to prove beyond almost any doubt that these same chemical changes can arise as a result of changes in our environment. Factors such as anxiety or stress, for example, or hormonal changes can affect neurotransmitter levels. Few doctors now hold to the view that depression is purely a biological disease arising from deficiencies in production of neurotransmitters. The brain is an incredibly complex place and we still understand relatively little about all of its functioning. My own view is that whilst it may be
possible to inherit a predisposition (or if you like a potential
tendency) to develop depression, the expression of this tendency will very
much depend on our environment, nutrition, lifestyle and our life
experiences -- particularly those of childhood where our "world
view" is being developed. Any potential tendency towards depression
can therefore either be ameliorated or increased, depending upon how we
have lived our lives. Back
to Top Taking a purely biological point of view, it seems fairly obvious that if depression is associated with shortages of certain key neurotransmitters then the "cure" for depression ought to be to address this deficiency, rather like the cure for scurvy is to supplement the diet with vitamin C. Although this is far from being the whole picture, this is pretty much how antidepressants work. The exact process is of course rather more complicated. After a nerve impulse has been carried across the synapse by a neurotransmitter like serotonin (see "the brain, neurons and synapses" above for an explanation of this - click here), the neurotransmitter is either broken down by enzymes and removed or taken back up again into the nerve ending and recycled for future use - a process known as re-uptake. Many of the main antidepressants work by blocking this recycling process. Antidepressants such as Prozac (fluoxetine) and Seroxat (paroxetine) are known as SSRIs -- standing for Selective Serotonin Reuptake Inhibitors. To think of such medication as merely being stimulants is therefore to grossly oversimplify their mode of action. Contrary to popular belief, SSRIs are not "happy pills". They do not directly enhance mood and they do not, of themselves, promote happiness. At best, they may give you the capacity to once again behave and think in ways that can lead to happiness. Some antidepressants, such as the examples mentioned above, work specifically on serotonin whilst others work on noradrenaline and a few (Effexor [venlafaxine], for example) work on both. When we are depressed we don't feel like doing the things that would be good for us and moreover our performance (for example at work or in school) is compromised. This means we don't achieve such good results and this can tend to lead to still greater levels of depression. One of the main benefits of antidepressants is that they can break this so-called "cycle of depression". Although antidepressants don't actually
change our world, they can at least give us the energy and perhaps just
enough enthusiasm to take the first steps towards re-engaging with our
lives. If we start to see better outcomes from our efforts in life then we
will tend to feel better about life and perhaps ourselves, which will
boost our confidence and lead to still greater levels of success and
enjoyment. In severe cases of depression the sufferer can be almost
physically incapacitated from undertaking everyday tasks and may start to
cope so badly with life that death seems as if it is the only viable
alternative. In such examples antidepressants can quite literally be
lifesavers. Back
to Top One client I worked with had very low
levels of assertiveness and because of this was often treated very badly
by friends, family and work colleagues. This led to her becoming really
rather depressed, which meant that she tended to avoid interactions with
other people whenever possible, lowering further still her confidence and
her ability to deal with social situations. She was becoming increasingly
withdrawn. Whilst the counselling helped her to understand how she was
contributing towards her own distress by having so low an opinion of
herself, the antidepressants helped her to feel well enough to start to
re-engage with people and to put into practice some of the ideas and life
skills she was learning in therapy. By the time the medication was slowly
stopped after her depression had lifted, she had firmly established new
patterns of behaviour and relationships. She was easily able to continue
this new and more useful way of being, therefore removing the need for
further medication. Back
to Top The Disadvantages of Antidepressants Many people I know would say that when you are profoundly depressed, there are no disadvantages to taking something that makes you feel better. Certainly I know many clients whose lives have been transformed by taking the right antidepressant, prescribed by their doctor or psychiatrist. Having said that, no medication is without its problems. With antidepressants, the main problems are firstly, finding the right antidepressant and secondly, side-effects. Antidepressants seem to help about half of the people who take them and different antidepressants work better with some people than others. The process of matching the right medication to the person is far from a precise science and one psychiatrist I know will admit that it often comes down to luck and guesswork. Having said that, the choice of
antidepressant is usually informed by the exact nature of the symptoms
experienced. For example, some antidepressants are associated with a
lowering of anxiety, others with sedation (useful in cases of severe
insomnia) and still others with a very low risk in case of overdose. It is
also important that the antidepressant is prescribed at the right dosage
and there is some evidence to suggest that some GPs err too much on the
side of caution here. All antidepressants have a slow onset of action,
with most taking at least two weeks to have any beneficial effect. It is
usually a month before the optimum level of efficacy is reached and up to
six weeks may be required for full effect.
Back
to Top Counselling and Antidepressants I am aware of a potential disadvantage in taking antidepressants when engaged in therapy. This is something that perhaps becomes significant if we take the view that depression can sometimes be a message from you to yourself, a message which is saying that you are not living your life in ways which are good for you. Clearly, not all instances of depression fit this description. However it is certainly the case that many clients become depressed as a result of having a rather distorted view of what is good for them. For example, some people who have been starved of love and approval in childhood or who have been given approval only when they met certain conditions placed upon them (such as excellent performance at school), will tend to spend their adult life seeking approval and perhaps suppressing their own needs in order to get it. This tends to disempower them and means that their sense of self worth can be conditional upon the varying and sometimes fickle views of people close to them. A natural consequence of this can be depression and also anxiety. As the saying goes, it is impossible to please all of the people, all of the time! If a person like this presents to their GP with depression, he or she may well receive antidepressant treatment. This may enable them to continue to live their life in ways which are fundamentally destructive to a fulfilling way of being. The medication may ease the symptoms and the consequences but it will not address the root cause of the disturbance. Moreover, antidepressant medication can actually insulate us from our feelings. As a therapist, I am perhaps concerned with putting my clients in closer touch with their feelings because I believe that, fundamentally, all of us knows what is good for us -- if only we can learn to trust our instincts. In theory therefore, antidepressant medication can, perhaps, interfere with that important process of a client becoming aware of and responding to, their true self. In short, the antidepressant may enable them to wear a mask of inauthenticity for a while longer. In practice, this is rarely a major problem
and may delay the process of counselling by a short amount of time.
However, it remains a consideration in some cases. Against this must be
considered the advantages of taking medication, especially where the
depression is severe enough to be incapacitating. If the client is
unable, for example, to go to work or to deal with their responsibilities
as a parent, then clearly it is more important to establish a basic level
of functioning. Similarly depression can sometimes be so disabling as to
render the process of counselling untenable because it precludes effective
psychological contact with the client. Again, in these cases
antidepressant and counselling need to work hand-in-hand if we are to be
of the greatest help. Back
to Top Although modern antidepressant choices have far fewer side-effects than was the case with some of the older, so-called, tricyclic antidepressants, this can nevertheless still be a problem. Drug manufacturers are increasingly designing antidepressants to have a highly specific mode of action, with only the selected neurotransmitter targeted. SSRIs, for example, are designed to be selective of serotonin but even so, this neurotransmitter also controls digestion, appetite, blood pressure, temperature control and sleep regulation. This is why SSRIs can sometimes be associated with unwanted effects such as sweating, weight gain and insomnia. In practice, the disadvantages of these unwelcome side-effects are far outweighed by the advantages. Nevertheless, many patients do stop taking their medication in the first few days when the side-effects (if they occur at all) are most likely to be at their worst. It is worth remembering that problems with side-effects usually decline after three to five days and most modern antidepressants are well tolerated. Other antidepressants impact on other neurotransmitter systems as a side effect of targeting those involved in depression. Zispin (mirtazapine) for example impacts on serotonin and noradrenaline levels but also affects the histamine system, meaning that it initially causes significant drowsiness in many patients. The same is also true for Dutonin (nefazodone). Against this, Zispin and Dutonin rarely have an adverse effect on sexual desire or performance, a characteristic unfortunately associated with some of the SSRIs. All the older tricyclic antidepressants are much less specific and so can potentially have a broader range of unwelcome effects such as dry mouth and blurred vision. Nevertheless, they still have their uses and I have sometimes seen my clients respond well when prescribed this type medication by their doctor, where the more modern alternatives have failed to be of benefit. Another characteristic to be aware of is that medication can sometimes be so effective as to make you feel that you no longer need to take it. After a time, you can become convinced that your depression is no longer a problem and indeed, it won't be, for as long as you continue to take the tablets! Remember, depression tends to be a longer term illness or condition and this means you may be taking antidepressants for many months, including a period of time during which you are feeling completely "back to normal". One of the most important factors in preventing a recurrence is a continuation of medication beyond the point where all symptoms have disappeared. Often, there is an easily recognisable point in time at which to stop, such as the resolution of problem or a point at which you feel you have come to terms with a situation -- perhaps as a result of counselling. In other cases, it may be necessary to take medication for extended periods, possibly as long as many years. The point at which you may be ready to stop is something you need to discuss carefully with your GP, and possibly with your therapist. Even then, it is important not to discontinue medication suddenly and your doctor may well discuss a regime for gradually reducing the dosage over several days or possibly weeks, depending on the type of medication and the dosage taken. No antidepressant can cause addiction, despite what may be claimed on TV! However, you may understandably feel a certain amount of trepidation about discontinuing treatment and coping without it, especially if you have taken it for many months or years. In practice, problems with discontinuation are rare. I myself have encountered only one client (out of the many hundreds that I have seen) who had significant problems whilst he was stopping antidepressant medication. Remember, if you are uncertain about how well your medication is working, or if you have questions or concerns about dosage, side-effects or discontinuation, you should always speak to your doctor. The information provided here is for general guidance only and is not intended to replace consultation with a medical practitioner. This antidepressant has received a great deal of publicity recently, much of it arising from a BBC 'Panorama' TV programme that was critical of the makers of the drug. According to recent publicity there is evidence to suggest that significant numbers of people are reporting unpleasant side effects. My own experience when working with clients taking this medication is that it is a highly effective antidepressant. In the first few days of treatment, some clients report feeling unwell; they may be nauseous or experience mild headaches or tingling sensations. These symptoms are not uncommon when taking other antidepressants and almost always disappear within 5-7 days. Out of hundreds of cases, I can think of only two clients who reported longer term side effects that were worrying or which caused distress similar to that reported in the Panorama programme. I have never experienced any client becoming violent or suicidal after taking the drug, where previously they did not have these feelings. When a drug is as widely prescribed as Seroxat, a tiny proportion that equates to say 1% of patients is equivalent to many people. If you are among the (let's say) 99% who do well with the medication then fine - you think of it as an effective medicine. However, if you are one of the unlucky few then clearly it seems you may have some cause for concern. These concerns should be addressed with a medical professional. My own view is that, purely on the basis of probabilities, you are unlikely to have an adverse reaction to Seroxat. You are most likely to find it a safe and effective antidepressant. If this describes you, you should not discontinue taking the drug. You may wish to discuss any concerns you may have with your doctor or psychiatrist however. Even if you feel you are experiencing side effects, it is unwise to discontinue use without first consulting your doctor. In my view the risks of untreated depression may be even greater. Even if you do decide to discontinue use, it is wise to do so under medical supervision. Your doctor may think it wise to suggest an alternative medication. Seroxat, as when stopping other antidepressants, should be discontinued gradually. Stopping medication suddenly may cause unpleasant symptoms, though these are short term and disappear once the drug is out of your system. Here are some links where you may find further information: Seroxat Users Group Media Articles |
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