A peer-reviewed medical journal runs an essay showing that claims by psychiatric drug industry about a “chemical imbalance” are unproven.

MindFreedom International News – 8 Nov. 2005

Millions of viewers have seen the TV ads for the anti-depressant drug Zoloft.

A bouncing ball turns from a sad face to a happy face. Like many ads for similar psychiatric drugs, the voice-over claims Zoloft helps correct a “chemical imbalance.”

The December 2005 issue of a peer-reviewed medical journal includes an essay by two scientific researchers that debunks psychiatric drug advertising claims about a “chemical imbalance.”

Countless consumers choose to take psychiatric drugs based on these claims.

Why would the US Food and Drug Administration approve false ads for the SSRI drugs?

The human rights group MindFreedom International has been asking that question for a long time.

On behalf of MindFreedom, US Senator Ron Wyden contacted the FDA for an explanation about why they approve such false advertising. In their response — which took over one year — the FDA could cite no scientific literature or studies.

It turns out there’s a good reason the FDA can’t find any scientific evidence for these ads.

The scientific evidence does not exist.

This new medical journal essay concludes, “The incongruence between the scientific literature and the claims made in FDA-regulated SSRI advertisements is remarkable, and possibly unparalleled.”


BELOW are links to the essay in both text and PDF print versions.

AT BOTTOM is a news release from the publishers of the journal entitled, “Ads for SSRI antidepressants are misleading, say researchers.”




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[forwarded from publisher:]


Contact: Paul Ocampo press at plos.org 415-624-1224 – Public Library of Science

Ads for SSRI antidepressants are misleading, say researchers

Consumer ads for a class of antidepressants called SSRIs often claim that depression is due to a chemical imbalance in the brain, and that SSRIs correct this imbalance, but these claims are not supported by scientific evidence, say researchers in PLoS Medicine.

Although scientists in the 1960s suggested that depression may be linked to low brain levels of the chemical serotonin (the so-called “serotonin hypothesis”), contemporary research has failed to confirm the hypothesis, they say.

The researchers — Jeffrey Lacasse, a doctoral candidate at Florida State University and Dr. Jonathan Leo, a neuroanatomy professor at Lake Erie College of Osteopathic Medicine — studied US consumer advertisements for SSRIs from print, television, and the Internet. They found widespread claims that SSRIs restore the serotonin balance of the brain. “Yet there is no such thing as a scientifically established correct ‘balance’ of serotonin,” the authors say.

According to Lacasse and Leo, in the scientific literature it is openly admitted that the serotonin hypothesis remains unconfirmed and that there is “a growing body of medical literature casting doubt on the serotonin hypothesis,” which is not reflected in the consumer ads.

For instance, the widely televised animated Zoloft (setraline) commercials have dramatized a serotonin imbalance and stated, “Prescription Zoloft works to correct this imbalance.” Advertisements for other SSRIs, such as Prozac (fluoxetine), Paxil (paroxetine), and Lexapro (escitalopram), have made similar claims.

In the US, the FDA is responsible for regulating consumer advertisements, and requires that they be based on scientific evidence. Yet, according to Lacasse and Leo, the mismatch between the scientific literature and the SSRI advertisements is “remarkable, and possibly unparalleled.”

And while the Irish equivalent of the FDA, the Irish Medicines Board, recently banned GlaxoSmithKline from claiming in their patient information leaflets that paroxetine (Paxil) corrects a chemical imbalance, the FDA has never taken any similar action on this issue.

Commenting on Lacasse and Leo’s work, Professor David Healy of the North Wales Department of Psychological Medicine, said: “The serotonin theory of depression is comparable to the masturbatory theory of insanity. Both have been depletion theories, both have survived in spite of the evidence, both contain an implicit message as to what people ought to do. In the case of these myths, the key question is whose interests are being served by a widespread promulgation of such views rather than how do we test this theory.”

Dr Joanna Moncrieff, Senior Lecturer in Psychiatry at University College London, said: “It is high time that it was stated clearly that the serotonin imbalance theory of depression is not supported by the scientific evidence or by expert opinion. Through misleading publicity the pharmaceutical industry has helped to ensure that most of the general public is unaware of this.”


Citation: Lacasse JR, Leo J (2005) Serotonin and depression: A disconnect between the advertisements and the scientific literature. PLoS Med 2(12): e392.

CONTACTS: Jeffrey Lacasse jeffreylacasse at comcast.net (850) 294-0875

Jonathan Leo jleo1 at tampabay.rr.com 941-321-9034 or 941-723-8710


All works published in PLoS Medicine are open access and may be freely re-distributed under the Creative Commons Attribution License.

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