Anti-Depressant Drugs: 12 Things You Should Know About Pills for Depression
Anti-depressant drugs are widely used in many countries as a treatment for depression. Depression is a disabling mental disorder characterised by enduring low mood and/or a loss of interest and enjoyment from day-to-day activities. In addition to these two key symptoms, for a doctor to conclude that you are suffering from depression some of the following signs would also need to be present: sleep disturbance, loss or increase in appetite, weight loss or weight gain, suicidal ideas, loss of energy, strong feelings of worthlessness or guilt, restlessness, poor concentration and indecisiveness.
Before taking anti-depressants it is important to be aware of the following pieces of information, some of which might not always be shared by the prescribing doctor.
1. Anti-depressants are of different types
If you are unfortunate enough to suffer depression, the treatment most likely to be offered is anti-depressant medication. First developed in the 1950s, there are now several different types which differ on the basis of their chemical structure and how they work. The three most common groups of anti-depressant medication currently prescribed are the Tricyclics, Selective Serotonin Re-uptake Inhibitors (SSRIs for short) and the Serotonin and Nor-adrenaline Re-uptake inhibitors (SNRIs for short). The drug companies, together with most psychiatrists, claim that these drugs work by increasing chemicals in the brain that affect our mood, namely nor-adrenaline (nor-epinephrine) and serotonin. However, there is little evidence for this mode of action.
Specific examples of these three popular groups of anti-depressant drugs, with brand names in brackets, are given in the table.
Amitriptyline (Triptizol, Elavil)
Citalopram (Cipramil, Celexa)
Fluoxetine (Prozac, Fontex)
Duloxetine (Cymbalta, Yentreve)
Paroxetine (Seroxat, Paxil)
Doxepin (Sinaquan, Adapin)
Sertraline (Lustril, Zoloft)
Imipramine (Tofranil, Janimine)
Lofepramine (Gamanil, Lomont)
2. Anti-depressants are less effective than often claimed
Drug company advertisements, along with doctors and psychiatrists, often claim that anti-depressant drugs are of great benefit to the majority of people who suffer depression. Indeed, in the United Kingdom the Royal College of Psychiatrists state on their website that, based on the relevant research, it is reasonable to conclude that between half and two-thirds of patients will be ‘much improved’ after three months of treatment.
However, a thorough inspection of the data leads to a radically different conclusion. When Irving Kirsch (a Professor of Psychology) and his colleagues conducted a comprehensive review of the evidence, including both published and unpublished studies, their conclusion was that the SSRIs were only effective in a very small number of the most depressed patients; for the great majority of people these modern, state of the art anti-depressants had therapeutic effects that were no better than that of a placebo (that is, the benefit people obtain from taking a pill that they believe will help when, in reality, they are taking an inert substance containing non of the active ingredient). Importantly, in severely depressed patients, the superiority of the anti-depressant may have been due to this group being less susceptible to the placebo (rather than to any enhanced responsiveness to the medication).
3. Anti-depressants are over-prescribed
Between 1995 and 2004 the number of anti-depressant prescriptions issued in the USA tripled so that, by 2005, 10% of the population (27 million people) were taking them. Similarly, 10% of middle aged adults across Europe had taken anti-depressants in 2010. Such remarkably high figures suggest that these drugs are too freely dispensed to patients, particularly when one considers that there are a range of alternative interventions (for example talking therapies or exercise) that are, in general, at least equally as effective. More worryingly, this increased prescribing of anti-depressants is not restricted to adults. In 2007 almost 110,000 children in the United Kingdom were taking these drugs, a 40% increase on the 1997 figure.
4. Anti-depressants cause unwanted side effects
All medications have side effects and anti-depressants commonly produce a range of unwanted consequences. Tricyclics are associated with dry mouth, hand tremor, racing heart, constipation, weight gain, drowsiness, low blood pressure, erectile problems and delayed ejaculation. SSRIs can cause increased anxiety, nausea, indigestion, aggression, agitation and sexual dysfunction. Although most of these side-effects disappear within a few weeks, they are unwelcome irritants for people already suffering depression.
5.Anti-depressants may cause an increase in suicidal feelings
A much more serious side effect has been occasionally reported, regarding young people experiencing an increase in suicidal feelings after taking SSRIs, an adverse reaction that led to a ban on the prescription of SSRIs to people under 18 years of age.
A recent (2012) study looking at the data obtained from 9000 young people did not find that Fluoxetine (a commonly prescribed SSRI) increased suicidal thoughts. It is also worthy of note, however, that neither did this study provide any evidence that this popular anti-depressant decreased such thoughts.
The evidence on this issue remains conflicting.
6. Trycyclic anti-depressants are dangerous in overdose
A drawback with the older, tricyclic anti-depressants is their high level of toxicity that renders them potentially lethal in overdose – a major concern for a medication prescribed for depressed people, where suicide risk is a common concern. The SSRIs are much less dangerous in overdose.
7. Anti-depressants do not rectify chemical imbalances in the brain
Contrary to the claims of the pharmaceutical industry and many psychiatrists, there is no consistent evidence that anti-depressants achieve their benefits via specific increases in the levels of nor-adrenaline and serotonin. It is likely that these medications affect numerous other neuro-transmitters in the brain.
Many anti-depressants produce a sedating effect and this is often the first thing that recipients notice upon commencing the drug. In keeping with other psychoactive drugs, anti-depressants are likely to reduce a person’s sensitivity to their environment. Given that depressed people often suffer with insomnia and agitation, the arousal reduction may be the most helpful consequence of the medication – the finding that other sedative drugs (benzodiazepines, anti-psychotics, opiates) can achieve an equivalent anti-depressant effect lends further support to this possibility.
Further information regarding the likely effects of anti-depressants on the brain can be obtained from the excellent book by Moncrieff (2009).
8. Anti-depressants may help with problems other than depression
Anti-depressant medication can benefit people suffering from other mental health problems, not just depression. There is evidence they can have a therapeutic effect with post traumatic stress disorder (PTSD), anxiety disorders (panic, obsessive-compulsive), chronic pain and eating disorders. The general sedative effects of anti-depressant medication (see section 7) may account for these reported improvements.
9. Many patients experience withdrawal symptoms once they stop taking anti-depressants
Although not addictive in the same sense as some other drugs such as diazepam (that produce cravings and require an increasing dose to achieve the same effect), anti-depressants are associated with a range of withdrawal symptoms, particularly if a person has been taking the medication for a long time. Up to one third of people suffer a withdrawal syndrome that can include: stomach upsets, flu-like symptoms, anxiety, dizziness, insomnia, irritability, nightmares, weepiness and feelings of electric shocks in the body. These withdrawals can last for up to two months.
Psychiatrists may often misinterpret some of these symptoms as “a return of the illness” and recommend re-starting the anti-depressants. To minimise the chances of experiencing withdrawals, it is advisable to taper off the dose of anti-depressant rather than stopping abruptly.
10. Most episodes of depression will improve without any treatment
Most people with depression will recover spontaneously within eight months without anti-depressants or any other form of treatment.
11. Doctors recommend that patients should continue taking anti-depressants beyond the point at which they feel better
Medical practitioners discourage patients from stopping the anti-depressant medication when they feel better and recommend that it is taken for at least six months. If the patient has suffered two or more episodes of depression, the doctor will advise taking the anti-depressants for a minimum of two years. Such recommendations are difficult to square with both the medication’s modest effectiveness and the likelihood of spontaneous improvement in depressive symptoms.
12. The myth that there is a type of depression that will only respond to anti-depressants
Psychiatrists often assert that there is a type of depression that has a primary biological cause and therefore can only be remedied by a biological treatment like anti-depressant medication. They refer to these types as a “biological depression” or a “depressive illness.” The research evidence does not support this assertion. Some depressed people respond well to anti-depressants, whereas some respond well to psychological treatments, but there is no reliable way of determining beforehand a type of depression that is immune to non-biological treatments.
References & further reading
Kirsch, I., Deacon, B.J., Huedo-Medina, Scoboria, A., Moore, T.J. and Johnson, B.T. (2008). Initial severity and anti-depressant benefits: A meta-analysis of data submitted to the Food & Drug Administration. PLoS Med 5(2) e45. do:10.1371/journal. Pmed.0050045.
Moncrieff, J. (2009). A Straight Talking Introduction to Psychiatric Drugs. PCCS Books. Ross-on-Wye.