It's Official: The Serotonin Myth of Depression is Dead

Patient Expert

"Serotonin and depression," reads the title to an editorial in the latest British Medical Journal. "The marketing of a myth," reads the subheading.

The author is David Healy, professor of psychiatry at Cardiff University. Just to show you how things have changed, sixteen years ago when I started writing about mental health, Dr Healy was a voice in the wilderness and the drug companies were marketing that depression and other mental illnesses were chemical imbalances of the brain.

How times have changed.

About 13 or 14 years ago, I caught Dr Healy on a live webcast delivering a grand rounds at UCLA. He may have been a voice in the wilderness, but even back then his peers took him seriously.

At his grand rounds talk, Dr Healy mentioned that a patient back in the seventies who complained of "nerves" was sent out the door with a tranquilizer such as Valium. A few years later, that same patient might be asking for Xanax for her panic attack. In the mid-nineties, that same patient, with the same symptoms, was telling her doctor she was depressed. A few years later, yet again, that same patient was likely once again to complain about anxiety.

Such is the power of drug company marketing.

According to Dr Healy, during the 1980s, the drug companies began marketing the illness rather than the drug. The industry capitalized on the publication of the DSM-III in 1980, which - among other things - came up with new classes of disorders for anxiety. Thus, Upjohn (since taken over by Pfizer) pushed Xanax for panic disorder.

In the mid-eighties, the SSRIs in development were first seen as non-habit-forming alternatives to tranquilizers. But the new drugs lacked the instant result of the old ones. So, instead, the drug companies targeted their product to treat depression and called them "antidepressants."

Trust me, Dr Healy isn't just making this up. In his BMJ editorial, he notes that back in the 1960s, the drug companies were first exploring other indications for the drug, such as hypertension or obesity.

Depression, he said, didn't look too promising. For one, clinical trials showed the old class of antidepressants, tricyclics such as imipramine, worked better. For another, even back then, researchers rejected the idea that lowered serotonin had something to do with depression.

Nevertheless, the drug companies succeeded in marketing the idea that depression was the real illness lurking behind anxiety. The rest is history.

According to Dr Healy:

The approach was an astonishing success, central to which was the notion that SSRIs restored serotonin levels to normal, a notion that later transmuted into the idea that they remedied a chemical imbalance. The tricyclics did not have a comparable narrative.

Dr Healy also compares lowered serotonin to Freud's notion of libido, "a piece of biobabble."

Serotonin is not irrelevant, Dr Healy says, but "do clinical trial data marketed as evidence of effectiveness make it easier to adopt a mythical account of biology?"

Dr Healy has not changed his tune since I first heard his live webcast all those years ago. What has changed is that SSRIs have gone off-patent. A year or two prior to his grand rounds - under apparent drug industry pressure - the University of Toronto reneged on a pending professorship. The case was settled out of court.

Also, back in the old days, the industry could easily mobilize academics on their payroll to counter the claims of isolated naysayers. Also, tellingly, it is fair to say that a decade ago the BMJ never would have published Dr Healy's piece as an editorial.

Now, with the drug industry out of the game, with no financial interest in mythologizing serotonin, at long last we are beginning to have a rational discussion.

Of all things, the next loud voice debunking serotonin is likely to be the drug industry, itself. This will happen when a new class of antidepressant eventually emerges, based on an entirely different neurotransmitter or other chemical. Forget about the serotonin, we are likely to hear. It's all about the glutamate - or the BDNF, or the microbes or the cytokines, you name it.

So it goes "

Further reading: The Chemical Imbalance Myth of Depression