• Home
  • Health & Wellness
  • Disclaimer
    • Terms of Use
    • Privacy Policy
    • DMCA Notice
Podcast
  • Home
  • Health & Wellness
  • Disclaimer
    • Terms of Use
    • Privacy Policy
    • DMCA Notice
24/7 Health News
No Result
View All Result
Home Article

Chemical imbalance theory of depression: clearing up some misconceptions

August 23, 2022
in Article
0
Chemical imbalance theory of depression: clearing up some misconceptions
file 20220823 17 2jwz2h

fizkes/Shutterstock

The scale of the response to our recent study finding that there was no support for the idea that low serotonin causes depression – the so-called “chemical imbalance” theory of depression – was enormous. Our paper is one of the 400 most shared of the 21 million papers that have ever been tracked. And our article in The Conversation was read by more than 1.3 million people. However, we feel that some of the responses missed the point, and we’d like to address those points here.

The main response from leading psychiatrists was that antidepressants work and it does not matter how. However, whether antidepressants work is not clear-cut, and how they produce their effects matters.

But first, we want to highlight a point skipped over by many commentators: for decades, people, including doctors, have been misled by false claims about what antidepressants are doing. The marketing line that antidepressants correct an underlying chemical imbalance has influenced people’s choices about their treatment, their self-perception, and their outlook on recovery.

We should acknowledge that people were misled and take stock of how corporate interests and marketing have affected medical discussions, otherwise we will be condemned to repeat these mistakes with new pharmaceutical products. For example, various unsubstantiated theories are currently circulating about how esketamine might rectify other chemical imbalances or other brain abnormalities.

Many people taking antidepressants get better, but whether they work or not is contested. The evidence for antidepressants’ effectiveness comes from randomised trials that show that people improve when they are given an antidepressant or a placebo.

On average, antidepressants reduce depression scores slightly more than a placebo. But the difference is small: two points on a 52-point depression scale. Evidence from large analyses of patient responses and National Institute of Health and Care Excellence guideline committees suggests that this is not a big enough difference to be noticeable by patients or doctors.

Even this difference may be exaggerated because antidepressants cause side-effects and other more subtle changes that let people know they are taking the active drug rather than the placebo, which may lead to amplified placebo effects.

Furthermore, the studies of antidepressants last for six to eight weeks and cannot provide evidence of whether taking antidepressants for longer periods is worthwhile, especially the months and years that many people take them for.

But even if we accept that the small difference between antidepressants and placebo is a real effect of the drug, there is no reason to assume, as many experts do, that it reflects the action of antidepressants on some underlying biological mechanism of depression.

Possible explanations for antidepressants small effect

First, although brain biology is involved in everything we think and feel, there are no established specific biological causes of depression. Other proposed ways in which antidepressants might target underlying mechanisms are hypotheses, often drawn from animal studies or cells in a dish and none have been consistently demonstrated in humans.

Second, there is another explanation for what antidepressants do. Antidepressants are drugs that change brain chemistry, and like other drugs that do this, they produce changes in our mental states and experiences. These changes can temporarily override our current feelings.

For example, alcohol has sedative and relaxing effects that can reduce anxiety and briefly “drown your sorrows”, but this is not because alcohol works on the underlying mechanisms of anxiety or depression. Alcohol’s effects (with individual variation) are experienced by everyone and not just people with one of these diagnoses.

Man pouring a large glass of whisky.
You change your brain chemistry with alcohol. That doesn’t make it an antidepressant.
Photographee.eu/Shutterstock

Antidepressants do not commonly make people merry like alcohol can. They cause a variety of more or less subtle mental alterations, depending on the chemistry of the drug. One common, dose-dependent alteration, is numbing of emotions.

This effect could also explain why antidepressants perform a little better than placebo in randomised trials. In the short term, the numbing may make people feel less depressed, but in the long term, the benefits are less clear.

This is why drawing analogies between antidepressants and paracetamol – as one commentator has done – is misleading. Paracetamol does not produce significant mental changes, and hence these cannot account for its effects on pain.

Unlike depression, we know there are specific biological mechanisms that produce pain, and we can therefore conclude that paracetamol is working through modifying these, even if we do not know exactly how it does so.

The mechanism of action of antidepressants is crucially important for considering the pros and cons of taking them, especially in the long term, given that we only have short-term trial data.

The idea that antidepressants correct an underlying chemical or other problem in the brain is reassuring – we do not have concerns about the long term use of insulin in diabetics. But if antidepressants are changing brain chemistry, without evidence they are rectifying anything, this is a different situation.

Other drugs that affect the way we feel and think by altering brain chemistry, such as alcohol and other recreational drugs, can cause concentration problems, sleep disturbance and withdrawal symptoms when they are used for long periods – all of which are concerns for antidepressants.

Lastly, we know more about what causes depression than is often thought. The number of stressors in life – job loss, relationship breakdown, physical illness – strongly predicts who will become depressed.

An over-emphasis on looking for the chemical equation of depression may have distracted us from its social causes and solutions. We suggest that looking for depression in the brain may be similar to opening up the back of our computer when a piece of software crashes: we are making a category error and mistaking problems of the mind for problems in the brain.

It would be wise to observe caution with drugs whose effectiveness is not certain, whose mode of action is unknown, and which have many side-effects, especially for use in the long term.

The Conversation

Mark Horowitz is a Collaborating Investigator on the RELEASE trial in Australia investigating supported, gradual, hyperbolic tapering of antidepressants. He is member of the Critical Psychiatry Network and an Associate of the International Institute for Psychiatric Drug Withdrawal (IIPDW). He is a co-founder of Outro Health which aims to use digital support to help people who wish to stop long-term antidepressant medication in Canada and the US using gradual, hyperbolic tapering.

Joanna Moncrieff is a co-investigator on a National Institute of Health Research funded study exploring methods of antidepressant discontinuation. She is co-chair person of the Critical Psychiatry Network, an informal and unfunded group of psychiatrists and an unpaid board member of the voluntary group, the Council for Evidence-based Psychiatry.

ShareTweetSharePin
Previous Post

Over-the-counter hearing aids have been greenlighted by the FDA – your local pharmacist will soon be able to sell you the device you need

Next Post

Long COVID: why it’s so hard to tell how many people get it

Next Post
Long COVID: why it’s so hard to tell how many people get it

Long COVID: why it's so hard to tell how many people get it

Most Read

What causes stuttering? A speech pathology researcher explains the science and the misconceptions around this speech disorder

What causes stuttering? A speech pathology researcher explains the science and the misconceptions around this speech disorder

December 15, 2022
morning back pain

Morning Again Ache Trigger Is Not the Mattress

October 11, 2021
lower back pain relief exercises

5 decrease again ache aid workouts

October 11, 2021
3 years after legalization, we have shockingly little information about how it changed cannabis use and health harms

3 years after legalization, we have shockingly little information about how it changed cannabis use and health harms

October 15, 2021
Nasal vaccines promise to stop the COVID-19 virus before it gets to the lungs – an immunologist explains how they work

Nasal vaccines promise to stop the COVID-19 virus before it gets to the lungs – an immunologist explains how they work

December 14, 2022
bleeding in gum

When The Bleeding in gum Is Severe ?

October 11, 2021
Good Night Sleep

6 Causes of Good Evening Sleep

October 11, 2021

COVID vaccines: how one can pace up rollout in poorer international locations

October 5, 2021
Ten small changes you can make today to prevent weight gain

Ten small changes you can make today to prevent weight gain

October 12, 2021
Support and collaboration with health-care providers can help people make health decisions

Support and collaboration with health-care providers can help people make health decisions

December 16, 2021
Greece to make COVID vaccines mandatory for over-60s, but do vaccine mandates work?

Greece to make COVID vaccines mandatory for over-60s, but do vaccine mandates work?

December 1, 2021

Multiple sclerosis: the link with earlier infection just got stronger – new study

October 12, 2021
News of war can impact your mental health — here’s how to cope

Binge-eating disorder is more common than many realise, yet it’s rarely discussed – here’s what you need to know

December 2, 2022
Nurses’ attitudes toward COVID-19 vaccination for their children are highly influenced by partisanship, a new study finds

Nurses’ attitudes toward COVID-19 vaccination for their children are highly influenced by partisanship, a new study finds

December 2, 2022
Kick up your heels – ballroom dancing offers benefits to the aging brain and could help stave off dementia

Kick up your heels – ballroom dancing offers benefits to the aging brain and could help stave off dementia

January 3, 2023
How hot is too hot for the human body? Our lab found heat + humidity gets dangerous faster than many people realize

How hot is too hot for the human body? Our lab found heat + humidity gets dangerous faster than many people realize

July 6, 2022
The promise of repairing bones and tendons with human-made materials

The promise of repairing bones and tendons with human-made materials

January 4, 2022
As viral infections skyrocket, masks are still a tried-and-true way to help keep yourself and others safe

As viral infections skyrocket, masks are still a tried-and-true way to help keep yourself and others safe

December 14, 2022
How regulatory agencies, not the courts, are imposing COVID-19 vaccine mandates

How regulatory agencies, not the courts, are imposing COVID-19 vaccine mandates

October 24, 2021
Heart disease risk from saturated fats may depend on what foods they come from – new research

Heart disease risk from saturated fats may depend on what foods they come from – new research

November 29, 2021
Late night eating may cause greater weight gain – new research points to why

Late night eating may cause greater weight gain – new research points to why

October 12, 2022

10 Things I Learned During My Body Transformation

October 12, 2021

7 Health Benefits of Sweet Potatoes

October 12, 2021
Nobel prize: how chilli peppers helped researchers uncover how humans feel pain

Nobel prize: how chilli peppers helped researchers uncover how humans feel pain

October 12, 2021
How air filters can make COVID wards safer for patients and staff

How air filters can make COVID wards safer for patients and staff

December 1, 2021
GPs don’t give useful weight-loss advice – new study

GPs don’t give useful weight-loss advice – new study

December 16, 2022
Four ways to avoid gaining weight over the festive period – but also why you shouldn’t fret about it too much

Four ways to avoid gaining weight over the festive period – but also why you shouldn’t fret about it too much

December 22, 2022
Five ways to avoid pain and injury when starting a new exercise regime

Five ways to avoid pain and injury when starting a new exercise regime

December 30, 2022
Why suicide prevention support is crucial for people with fetal alcohol spectrum disorder

Why suicide prevention support is crucial for people with fetal alcohol spectrum disorder

September 28, 2022
Too hot to handle: Climate considerations for youth sport during the hottest years on record

Too hot to handle: Climate considerations for youth sport during the hottest years on record

July 19, 2022
  • Home
  • Health & Wellness
  • Disclaimer

© 2020 DAILY HEALTH NEWS

  • Home
  • Health & Wellness
  • Disclaimer
    • Terms of Use
    • Privacy Policy
    • DMCA Notice

© 2020 DAILY HEALTH NEWS