A high-profile doctor in the United Kingdom has claimed the link between serotonin and depression is largely a myth, and there is no evidence popular anti-depressants have any long-term beneficial effects.
In an editorial published today by the prestigious British Medical Journal, professor of psychiatry David Healy argues the success of serotonin reuptake inhibiting drugs, known as SSRIs, is down to patients' beliefs the drugs "restored serotonin levels to normal, a notion that later transmuted into the idea that they remedied a chemical imbalance".
Prof Healy says this is the "marketing of a myth", because there is no evidence SSRIs – which include popular anti-depressants such as paroxetine (Aropax, Paxil) and fluoxetine (Prozac) – have any effect on serotonin levels in the brain, nor that low serotonin levels are the primary cause of clinical depression.
SSRIs first came onto the market in the 1980s and quickly replaced tricyclic medications, which tended to have more side-effects. They were marketed as fixing the root causes of depression and anxiety – a serotonin imbalance – rather than just treating the symptoms.
"For doctors it provided an easy shorthand for communication with patients," writes Prof Healy.
"For patients, the idea of correcting an abnormality has a moral force that can be expected to overcome the scruples some might have had about taking a tranquilliser, especially when packaged in the appealing form that distress is not a weakness."
In the 30 years since then, Prof Healy says research has cast doubt on the central premise behind SSRIs – that depression is caused by a serotonin imbalance. Ketamine, for example, seems to be more effective than SSRIs in treating severe cases such as melancholia, without affecting serotonin levels at all. And despite the greater risk of side-effects, the older tricyclic medicines were stronger – but without a "comparable narrative", lost out to SSRIs in the marketplace.
"In other areas of life the products we use, from computers to microwaves, improve year on year, but this is not the case for medicines, where this year's treatments may achieve blockbuster sales despite being less effective and less safe than yesterday’s models.
"The emerging sciences of the brain offer enormous scope to deploy any amount of neurobabble."
Tricyclic medicines are still prescribed for depression, but usually only after SSRI medications have been tried first.
Prof Healy says serotonin is not completely "irrelevant", but assuming SSRIs alone can fix depression is "a plausible but mythical account of biology".
In 2012 Prof Healy authored a book, Pharmageddon, which heavily criticised large pharmaceutical companies and how they tend to "overhype benefits and deny real hazards" of the drugs they produce.
3 News
source: newshub archive
