Popular asthma drug may be linked to serious mental health problems

Government researchers have found that a widely prescribed asthma drug originally sold by Merck & Co may be linked to serious mental health problems for some patients, according to a scientific presentation reviewed by Reuters.The US researchers found that the drug, sold under the brand name Singulair and generically as montelukast, attaches to multiple brain receptors critical to psychiatric functioning.Singulair was a blockbuster product for Merck after its launch in 1998, offering relief in a pill as an alternative to an inhaler.In early advertising, the company said the side effects were so benign that they were “similar to a sugar pill,” while the label said any distribution in the brain was “minimal.” Generic versions are still prescribed to millions of adults and children every year.But by 2019, thousands of reports of neuropsychiatric episodes, including dozens of suicides, in patients prescribed the drug had piled up on internet forums and in the US Food and Drug Administration’s tracking system.

Such “adverse event” reports do not prove a causal link between a medicine and a side effect, but are used by the FDA to determine whether more study of a drug’s risks are warranted.After years of analysis, the reports and new scientific research led the FDA in 2020 to add a “black box” warning to the montelukast prescribing label, flagging serious mental health risks like suicidal thinking or actions.The agency also convened a group of internal experts around the same time to look into why the drug might trigger neuropsychiatric side effects.The results of the group’s work, which are preliminary and have not been previously reported or released publicly, were presented to a limited audience at the American College of Toxicology meeting in Austin, Texas on Wednesday.The FDA said it does not plan to update the drug label based on data from the presentation.The behavior of montelukast appears similar to other drugs known to have neuropsych...