Suicide warning for a commonly used drug after research shows the pill can reshape the brain

An asthma drug taken by hundreds of thousands of Britons could increase the risk of suicide, US research suggests.

Montelukast, sold under the brand name Singulair, is a widely prescribed drug in Britain and was dispensed more than 4 million times in England last year, NHS-backed data shows.

But new US government-backed research has found that it can cross the blood-brain barrier – a membrane designed to protect the brain – and attach to cells that regulate our mood and impulse control.

The research was prompted by reports of children who committed or attempted suicide while taking the drugs, some as young as five years old.

Now there are concerns that the estimated 350,000 Britons who use the drug, including 35,000 children, could be living with a similar risk.

Montelukast, given as a daily pill, works by blocking chemicals released by the body that cause the airways to swell and constrict during an asthma attack.

It has been available since the 1990s and is usually prescribed to asthma patients whose condition cannot be controlled with usual treatment.

Controversy surrounding the drug — and its potential to cause suicidal thoughts — has been circulating for years.

Montelukast, sold under the brand name Singulair, is a commonly prescribed drug in Britain and was dispensed more than 4 million times in England last year, NHS-backed data shows.

Campaigners have repeatedly called for more efforts to make patients and parents aware of the potential risk.

These calls have now been amplified after the results of a study into the drug and its impact on the brain were announced in the US.

At the annual meeting of the American College of Toxicology earlier this month, representatives from the U.S. Food and Drug Administration National Center for Toxicological Research confirmed that there is a link between the drug and psychiatric conditions.

They said laboratory tests had shown ‘significant binding’ of montelukast to multiple receptor cells in the brain and that this is highest in cells known to be involved in psychiatric effects.

However, the experts did not suggest that the drug should be withdrawn from the market or banned, adding that studies are still ongoing and results have not yet been finalized.

Patient safety leaflets distributed with montelukast in Britain describe the risk of suicidal thoughts as ‘very rare’, occurring in only one in 10,000 patients.

Britain’s medicines regulator, the Medicines and Healthcare products Regulatory Agency (MHRA), said more prominent warnings will be added to leaflets distributed with the drug this year.

These are similar to those that the US equivalent of the MHRA has added. They have highlighted the potential risk of ‘serious neuropsychiatric events’ when taking montelukast since 2020.

Yael’s mother Le’at, 41 (right), a graphic designer, noticed a change in her daughter’s behavior and attitude and began researching all of her daughter’s asthma medications. Ms Borger was shocked to discover that montelukast had ‘suicidal ideation’ as a side effect

The MHRA has consistently stated that the benefits of montelukast outweigh the risks for most patients.

Drug safety incident reports submitted to the regulator recorded five reports of suicide among patients taking montelukast – three of these among people aged between 10 and 19 years.

Such reports, which may be made by the public or by doctors, are not a guarantee that a particular drug is linked to an adverse event. Such events could possibly be mere coincidence.

The MHRA has also previously stated that it has received more than 1,200 reports of suspected neuropsychiatric reactions to montelukast since the drug was approved in Britain in 1998.

About 500 of these were among children under the age of 10.

Britons who have lost children to suicide or suffered near misses while taking the drug have insisted there is a link.

One case is that of Harry Miller from London, who died by suicide in 2018 at the age of 14 after taking the drug.

Montelukast has been available since the 1990s and is typically prescribed to asthma patients whose condition cannot be controlled with the usual treatment, inhalers.

James Burke from Leeds, who died by suicide aged 21 in April 2017 after suffering years of anxiety and depression, is another whose death has been linked to the drug.

His mother Sharon said in the aftermath: “James made the final decision to commit suicide, but that drug [montelukast] put him in the spirit to do it.”

Another was from London, England, who was 14 when he died by suicide in 2018 after taking the asthma drug.

And in 2019, the Mail on Sunday shared the story of Yael Borger who, at the age of 16, was gripped by suicidal thoughts that she believed were caused by the drug.

Harry Miller’s father Graham said he welcomed the MHRA’s new commitment to make warnings about the drug’s potential risks clearer earlier this year.

“We think it gives some meaning to Harry’s death because it warns other children of the dangers,” he said The Guardian.

Estimates about the number of patients taking montelukast come from a British campaign group concerned about the drug’s potential health effects.

Montelukast was originally developed by the German pharmaceutical company Merck.

Organon, a Merck spin-off that now markets Singulair, said in a statement after news of the U.S. study last week that it is confident in the drug’s safety profile.

“The product label for Singulair contains appropriate information about the benefits, risks and reported side effects of Singulair,” the company said.