Researcher Challenges Clinical Effectiveness of Antidepressants


In a new article, Michael P. Hengartner, a clinical psychologist at the Zurich University of Applied Sciences, writes that antidepressants are “largely ineffective across the whole severity spectrum.” The paper, published online ahead of print in BMJ Evidence-Based Medicine, addresses common misinterpretations of the efficacy research on antidepressant medications.

Hengartner notes that a large recent study claimed to find that antidepressants are efficacious medications for depression, with similar effects no matter how severe the depression symptoms. These conclusions have been broadly reported in the mass media as evidence that antidepressants “work.” However, other researchers have critiqued this study’s conclusions.

“Obviously, commentators and authors want to disseminate the message that antidepressants are an effective treatment for mild to moderate depression and that practice guidelines should incorporate these findings,” Hengartner writes. “However, neither the original paper nor the editorial does, in fact, provide evidence that the drugs are clinically effective for any form of depression.”

In these recent studies, the effects of antidepressants are indeed similar whether dealing with mild, moderate, or severe depression; however, the effect itself is incredibly small and is not clinically meaningful. In fact, the researchers report a drug-placebo difference of 1.6 points on the 52-point HRSD (scale for measuring depression severity). That is, on average, people taking the drug did not even improve 2 points more than those on a fake pill.

“In fact,” Hengartner writes, “what their and related findings reveal is that antidepressants are largely ineffective across the whole severity spectrum, because a 1.6 point drug-placebo difference is a negligibly small effect.”

“Clinical response” has been defined in the research literature as a 10-12 point improvement, and previous studies have found that clinicians are unable to even detect up to a 7-point improvement on the HRSD.

Another study published this year by Hengartner, with Jules Angst and Wulf Rossler, found that after 30 years people who took antidepressants had worsening symptoms over time. The finding remained even after controlling for multiple confounding variables—including depression severity. That is, people with the same diagnostic level of depression did better if they were not taking antidepressants.

A recent Mad in America article covered that study in the context of the research showing worse outcomes, biased research, and the side-effect burden that accompanies antidepressant use. Mad in America also published an interview with Hengartner, in which he explained in more detail his study on the long-term effects of antidepressants.

“Instead of urging evermore drug prescriptions, I suggest that researchers should scrutinize whether antidepressants work for any form of depression in a clinically meaningful way by balancing risks and benefits.”



Hengartner, M. P. (2018). What is the threshold for a clinical minimally important drug effect? BMJ Evidence-Based Medicine, Epub ahead of print: [7 Sept, 2018]. doi:10.1136/ bmjebm-2018-111056 (Link)


  1. Write about phenomenology of the psyche not about the interests of drug industry.

    I assume you want to help people, so write about the need of depression in today crazy reality for psychopatic brainless heroes.

    James Hillman, Re -visioning of psychology. The first 60 pages, should help.
    Thank you.

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  2. “Instead of urging evermore drug prescriptions, I suggest that researchers should scrutinize whether antidepressants work for any form of depression in a clinically meaningful way by balancing risks and benefits.”

    Yes, please. That would be great. Psych drug makers and doctors clearly have an agenda to keep the public thinking that these pills help.

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  3. Thanks for keeping the spotlight on this.

    Its is incredible the excuses the “experts” give for why, despite the evidence, AD’s work:

    (1) “Some people get better on AD’s” Don’t mention that they also do on placebo.
    (2) “Clinical Experience”. Yes that gave us insulin coma therapy.
    (3) “The RCT’s are flawed”. Well, yes, they did not disclose all the negative stuff that they should have.
    (4) “Placebos are getting too good”. For heavens sake. A true placebo would be an active placebo with similar side effects like dry mouth – these studies apparently show AD’s to be even worse.
    (5) “all the studies show they prevent suicides”. To my knowledge, there aren’t any convincing studies that show this. Amongst under-18’s, we have rising suicide and rising AD rates.
    (6) “they aren’t perfect, but they are getting better”. Top of the league in the Cipriani study (probably due to unblinding and sedation) by a distance was amytriptaline, discovered in 1960 and not reccomended because it is potentially lethal.
    (7) “the placebo effect alone is worth having”. But it is not ethical to prescribe a drug which has no therapeutic effect and will quite likely damage you.

    The story is out, it really is. I’m just a carer, nothing special, and I know others in my position who know the full story now and will never be fooled.

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  4. The people on the units of the “hospital” where I work who know that there are no chemical imbalances get drugged the worst of anyone if they try to state this in public. I’ve watched it done to people. Many so-called “patients” are quite aware that none of the psych drugs work, neither neuroleptics or so-called antidepressants. But if they’re smart they won’t stand up and say anything because then they become the target of the drugging and the staff say that what they’re saying shows just how ill they truly are.

    How does anyone look at themselves in the mirror each and every morning and then go to work and state that these drugs work and that they take care of chemical imbalances? Just explain that to me!

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