The US FDA has required the asthma and allergy drug montelukast (Singulair/Merck, and generics) to carry a black box warning over serious mental health side effects, according to an agency alert on Mar 4.

Montelukast is currently approved by the FDA to prevent asthma exacerbation and symptoms including wheezing and shortness of breath and to relieve symptoms of allergic rhinitis, according to WebMD. But the FDA now reports the mental health risks associated with the drug mean healthcare professionals should seek alternative treatments for patients with allergic rhinitis.

“We are requiring a Boxed Warning, our most prominent warning, to be added to the prescribing information of montelukast to describe these serious mental health side effects. … Because of the risk of mental health side effects, the benefits of montelukast may not outweigh the risks in some patients, particularly when the symptoms of disease may be mild and adequately treated with other medicines,” the FDA said in the alert.

The FDA recommended:

  • For allergic rhinitis, also known as hay fever, we have determined that montelukast should be reserved for those who are not treated effectively with or cannot tolerate other allergy medicines.
  • For patients with asthma, we recommend that healthcare professionals consider the benefits and risks of mental health side effects before prescribing montelukast.

The agency’s decision strengthens existing warnings about serious behavior and mood-related changes in patients using montelukast.

The FDA said: “We are taking this action after a review of available information led us to reevaluate the benefits and risks of montelukast use. Montelukast prescribing information already includes warnings about mental health side effects, including suicidal thoughts or actions; however, many health care professionals and patients/caregivers are not aware of the risk. We decided a stronger warning is needed after conducting an extensive review of available information and convening a panel of outside experts, and therefore determined that a Boxed Warning was appropriate.”

The FDA advised healthcare professionals to:

  • Consider the risks and benefits of montelukast when deciding to prescribe or continue patients on the medicine;
  • Counsel all patients receiving montelukast about mental health side effects, and advise them to stop the medicine and contact a healthcare professional immediately if they develop any symptoms included but not limited to those listed in the table above;
  • Be aware that some patients have reported neuropsychiatric events after discontinuation of montelukast.
  • Only prescribe montelukast for allergic rhinitis in patients who have an inadequate response or intolerance to alternative therapies.

More information is available on the FDA’s website.