Millions of people in the UK rely on antidepressants and anxiety medications to manage their mental health—but a new study is raising serious questions about their long-term impact.

Scandinavian researchers are now suggesting that these commonly prescribed drugs may be linked to an increased risk of developing motor neurone disease (MND), including its most well-known form, ALS (amyotrophic lateral sclerosis).

This possible connection has caught the attention of health experts across the globe.

But as with any study of this nature, not everyone is convinced by the findings just yet.

Antidepressants and Anxiety Meds May Raise the Risk of MND

The new study looked into medications used to treat depression, anxiety, sleep disorders, and even sedatives.

What researchers found was striking: being prescribed any of these medications just twice in a person’s lifetime was associated with a higher chance of developing motor neurone disease.

Specifically:

Anxiolytics (used to treat anxiety) were linked to a 34% increased risk
Antidepressants were tied to a 26% increased risk
Sleeping pills and sedatives showed a 21% increased risk

And here’s the kicker—the increased risk still held even when the medications were taken more than five years before diagnosis.

What Exactly Is Motor Neurone Disease?

Motor neurone disease is a devastating condition that affects around 5,000 people in the UK.

It gradually destroys the nerves controlling muscles, leading to muscle weakness, loss of speech, trouble swallowing, and eventually the inability to move or even breathe.

ALS, the most common form of MND, is famously known as the illness that affected physicist Stephen Hawking.

There’s currently no cure, and treatment options are limited, making any new research into causes or early warnings particularly important.

Scientists Say: Don’t Jump to Conclusions Just Yet

While the results of the study might sound alarming, many scientists are urging caution.

According to Professor Ammar Al-Chalabi, a genetics expert at King’s College London, there’s an important distinction between correlation and causation.

“Just because someone took antidepressants before being diagnosed doesn’t mean the meds caused the disease,” he explained.

Instead, he suggests the real reason might lie in genetics.

Some people who are genetically predisposed to mental health conditions like schizophrenia may also be more likely to develop ALS.

In other words, the underlying risk for both might come from the same genetic source—not the medication.

Could Psychiatric Symptoms Be Early Warning Signs?

Interestingly, the study also raises the possibility that psychiatric symptoms like depression and anxiety might actually appear before MND develops.

This would mean medications aren’t causing the disease—they’re just being prescribed in response to early signs that something else is going wrong in the brain.

The Scandinavian researchers themselves note that depression, anxiety, and sleep disorders have been shown to negatively affect brain cells and could trigger changes in the brain that are also seen in MND.

What the Study Looked At and How It Was Conducted

The research, carried out in Sweden, examined 1,057 people who were diagnosed with MND between January 2015 and July 2023.

Their average age was 67. Researchers then compared their medication histories with those of healthy individuals in a control group.

The goal? To see if there were any major differences in medication use that could help explain the development of MND.

The study followed each patient for an average of just over a year after diagnosis.

Their findings were published in the medical journal JAMA Open Network.

Could These Drugs Make the Disease Progress Faster?

There was another concerning discovery: people who had taken antidepressants before diagnosis also seemed to experience a quicker functional decline.

This means their symptoms worsened at a faster rate, though again, it’s unclear whether the medication was the cause or simply an early marker of the disease.

Lead researcher Dr. Charilaos Chourpiliadis emphasized that while the link is worth exploring, more research is needed.

He believes that keeping a closer eye on younger patients with psychiatric symptoms could potentially lead to earlier diagnosis of ALS.

Are Genetics Playing a Bigger Role Than We Thought?

Experts also pointed out a key detail: genetic factors may have played a major role in the findings.

According to Dr. Brian Dickie from the MND Association, a common genetic marker linked to ALS—the C9orf72 gene—is especially prevalent in Scandinavian populations.

This genetic factor is not only tied to a higher risk of developing ALS but is also linked to faster progression and shorter survival once the disease appears.

That might explain why people with psychiatric medication histories seemed to decline more quickly.

What Does This Mean for Mental Health Treatment?

The study doesn’t suggest people should stop taking antidepressants or anxiety medications—far from it.

The mental health benefits of these drugs are well-established, and they’re a lifeline for millions.

But it does highlight the need for more targeted research, especially when it comes to understanding how psychiatric symptoms might be early clues for neurological conditions like ALS.

For now, experts recommend watchful awareness, not panic.

As Professor Al-Chalabi said, the story is far from simple—and this is just one piece of a much larger puzzle.

What’s Next in the Search for Answers?

With new research constantly emerging and documentaries shedding light on diseases like MND, there’s growing interest in how early detection could make a difference.

If future studies confirm that certain medications—or the conditions they’re used to treat—are linked to MND, it could change how doctors monitor and support at-risk patients.

For now, this latest study serves as a reminder of how deeply connected mental and neurological health might be—and why science must continue to explore those connections with care.