U.S. FDA Now Requires Boxed Warning For Asthma Drug Montelukast Due To Side Effects

The Food and Drug Administration (FDA) in the United States now requires a boxed warning about the mental health side effects for montelukast, a popular asthma and allergy drug prescribed for adults and children age 1 and older.

"We decided a stronger warning is needed," read the FDA statement dated March 4, 2020, adding that a boxed warning for montelukast is more appropriate than the current warning label about the mental health risks tied to the drug.

Since 2008, Montelukast, which was first approved in 1998, has carried warnings of its adverse effects such as agitation, anxiousness, aggression, dream abnormalities, depression, and insomnia. 

Due to continued reports of adverse incidents, including suicides, related to the drug, the FDA conducted a review and analysis of montelukast's risks and benefits in 2017. The results showed that montelukast drastically increases the chances of neuropsychiatric problems, such as aggressive behavior, nightmares, and depression in those who take it. (Read more about it here.)

Dr. Sally Seymour, M.D., the director of the Division of Pulmonary, Allergy and Rheumatology Products in the FDA's Center for Drug Evaluation and Research, said via a statement, "The incidence of neuropsychiatric events associated with montelukast is unknown, but some reports are serious. Many patients and health care professionals are not fully aware of these risks."

The benefits of montelukast may not outweigh the risks in some patients

The 2017 findings stressed that the adverse effects, except for nightmares, do not show a clear cause-and-effect relationship — some neuropsychiatric issues may be directly caused by the drug or it may not. Doctors may still prescribe montelukast to patients with adequate warnings.

However, the FDA determined that the risks of montelukast, which comes in tablet form and chewable ones for kids, may outweigh the benefits for some patients. For patients with allergic rhinitis, in particular, the agency stressed that montelukast should only be reserved for those who are not responding adequately to or have difficulty tolerating other medications.

"There are many other safe and effective medications to treat allergies with extensive history of use and safety, such that many products are available over the counter without a prescription," said Dr. Seymour.

Patients whose asthma and allergy symptoms are mild may be treated with alternative medications and therapies. These include allergy shots, steroid nasal sprays, and antihistamines drugs such as loratadine (Claritin), fexofenadine (Allegra), cetirizine (Zyrtec), levocetirizine, and diphenhydramine (Benadryl).

In addition to the boxed warning, the FDA also requires doctors to provide a new medication guide with each montelukast prescription.

For more information about asthma attacks, click here. If your child has allergic rhinitis, click here for tips on how to allergy-proof your home.