A recently-published paper about treatment of depression made a bit of a splash. The review, led by Joanna Moncrieff from University College London and published in the peer-reviewed journal Molecular Psychiatry, looked at evidence around the “chemical imbalance” theory of depression – that it is caused by low levels of serotonin. It found there wasn’t enough evidence to say the two things are definitely linked.
The chemical imbalance theory has been around for decades, but some researchers have doubted it for a long time. Some experts have said this review proves that treating depression with SSRIs (a common type of anti-depressant which increases serotonin levels) does not work, and that the only reason many doctors prescribe these drugs is because of encouragement from pharmaceutical companies wanting to increase profits.
On the other hand, the fact is that SSRI anti-depressants seem to work to resolve depression in some people. It may be that there is some link between serotonin levels and depression after all, but given other research into placebos, I personally would not be surprised if in cases where they have worked it may have been due to placebo, or the other factors such as talking therapy or lifestyle changes that the medication was combined with.
As all of my research for the textbook, Psychophysiologic Disorders, showed, there are cases when a doctor taking an interest, speaking to a patient and prescribing medication can work wonders, even if the medication itself is not effective. But as the review author points out, it is not ethical to prescribe drugs if you are sure their only effect is as a placebo.
The issue is still uncertain, and there is a lot that psychologists and other medics don’t fully understand about depression. It is a very common condition, and may have a variety of contributing factors and treatments – each of which tends to be unique to the individual concerned. This review serves to highlight the fact that regardless of whether these anti-depressants are effective or not, depression has never been an illness which can be “fixed” with one magic pill. Doctors often take a broad approach, including medication, talking therapy and lifestyle changes.
These findings may lead to more conversations about the efficacy and ethics of SSRIs. However, they will not change the fact that the only way to have a chance of treating depression is on a case-by-case basis, taking into account each person’s unique situation, symptoms, and possible treatments.