Montelukast, most commonly known as Singulair, was approved by the FDA on Feburary 3, 1998. Singulair is a once-a-day pill for the prevention and chronic treatment of asthma, and is not for use during asthma attacks. Singulair is in a class of asthma medications called leukotriene inhibitors. Leukotrienes are chemicals that one's body releases only when a person breathes in pollen, or any other type of allergen. These chemicals cause tightening in the lungs, which ultimately results in asthma. Singulair is taken once per evening and comes in a pill form to swallow, an oral granule form to drink, and a chewable form.

Singulair Linked to Serious Neuropsychiatric Side Effects and Churg-Strauss Syndrome

When Singulair came onto the market in 1998, it was viewed as the life-saving option for the nearly 10 million adults and five million children living in America with asthma. As the years progressed, Singulair began to cause life-threatening side effects. Neuropsychiatric events such as postmarket cases of agitation, aggression, anxiousness, dream abnormalities and hallucinations, depression, insomnia, irritability, restlessness, suicidal thinking and behavior (including suicide), and tremor are common in 46% of all patients. Another dangerous side effect of Singulair is its association with Churg-Strauss Syndrome. Churg-Strauss Syndrome is a three-stage disease. The first stage often involves the sinuses and the onset of allergies not previously had. The second stage involves the onset of acute asthma, while the third and final stage involves various organ systems breaking down. Oftentimes, the patient will experience severe nerve pain in their arms, legs, and hands. Sores and purple marks appear and damage the kidneys, heart, and liver. Less serious side effects of Singulair include rash, fever, and fatigue.

FDA Issues Singulair Warning 

In 2008, 39 suicides resulted because of Singular. This prompted the FDA to conduct their own study regarding the asthma drug. On June 12, 2009, the FDA issued their results report stating that leukotriene inhibitor drugs can cause neuropsychiatric effects such as agitation, aggression, anxiousness, dream abnormalities and hallucinations, depression, insomnia, irritability, restlessness, suicidal thinking and behavior (including suicide), and tremor.

8/28/2009
Updated Information
FDA and the manufacturers of Singulair (montelukast), Accolate (zafirlukast), Zyflo (zileuton) and Zyflo CR (zileuton extended release) are announcing an update to the Precautions section of the prescribing information to include information about neuropsychiatric events reported in patients using these products.

FDA's request for the addition of this information to the prescribing information for these products was described in the Agency's June 2009 "Update to the Follow Up to the Early Communication about an Ongoing Safety Review for Leukotriene Inhibitors."

6/12/2009
Updated information
Neuropsychiatric events have been reported in some patients taking montelukast (Singulair), zafirlukast (Accolate), and zileuton (Zyflo and Zyflo CR). FDA has requested that manufacturers include a precaution in the drug prescribing information (drug labeling).

Montelukast is used to treat asthma, and the symptoms of allergic rhinitis (sneezing, stuffy nose, runny nose, itching of the nose), and to prevent exercise-induced asthma. Zafirlukast and zileuton are used to treat asthma.

The reported neuropsychiatric events include postmarket cases of agitation, aggression, anxiousness, dream abnormalities and hallucinations, depression, insomnia, irritability, restlessness, suicidal thinking and behavior (including suicide), and tremor.

This information reflects FDA's current analysis of available data concerning this drug.

To report any serious adverse events associated with the use of this drug, please contact the FDA MedWatch program using the contact information at the bottom of this web page.