Singulair is a popular medication used to treat asthma and allergic conditions. In particular, it is prescribed for regular use to prevent wheezing attacks and the shortness of breath that frequently accompany asthma episodes. Unlike most other medications used for the treatment of respiratory distress, which usually goes to market as inhalers, Singulair is an oral medication and not an emergency treatment for sudden asthmatic episodes. Manufactured by Merck, Singulair has gained in popularity over the years and represents a substantial profit center for the global drug manufacturer. Despite its popularity, Singulair’s profile has suffered in recent years after questions were raised concerning its links to suicidal behavior in pediatric patients. On March 4, 2020, the U.S. Food and Drug Administration (FDA) announced that the agency would, going forward, require Singulair to carry a revised “black box” warning concerning the potential for “neuropsychiatric events” associated with its use.
Prescription Name and Overview
Singulair is the product name for the prescription drug montelukast. It is available by prescription only and is used for the treatment of asthma and seasonal allergic rhinitis (hay fever). Singulair is known as an oral leukotriene receptor antagonist. The name derives from its action with respect to leukotrienes – naturally occurring chemicals in the human body which promote the inflammation associated with asthma and allergies. Singulair works to inhibit the ability of leukotrienes to bind to cells which are key to inflammation. It was approved by the FDA in 1998 and cleared for use with children as young as six (6) months in age.
Generic Name and Overview
Therapeutic equivalents to Singulair are marketed under the name montelukast.
OTC Name and Overview
Manufacturer
Merck & Co. (Kenilworth, New Jersey)
Labeled Indications
- Prevention and chronic treatment of asthma in patients twelve (12) months of age and older.
- Acute prevention of exercise-induced bronchoconstriction (EIB) in patients six (6) years of age and older.
- Relief of symptoms of allergic rhinitis (AR) in patients two (2) years of age and older; and “perennial” allergic rhinitis (PAR) in patients six (6) months of age and older.
Dosages
Singular is available both in a chewable tablet and graule forms and is typically prescribed in the following fashion:
- One 10mg tablet daily for adolescents (15 years and older) and adults;
- One 5mg chewable tablet daily for children ages 6-14; and
- One 4mg chewable tablet daily for children ages 2-5.
What Is It Used For?
Singulair is proficient in helping to prevent or ameliorate the most severe conditions associated with asthma attacks: wheezing and shortness of breath. Additionally, Singulair can help decrease the frequency of asthma attacks and/or prevent attacks associated with exercise. Singulair is different from emergency inhaler treatments for asthma as it is a once-daily pill or chewable tablet. It is not taken in response to a particular attack episode but instead is taken on a prescribed regimen. It remains in the body and helps act as a barrier between leukotrienes and cells which promote inflammation during asthmatic episodes.
How Does it Work?
Singulair is a leukotriene receptor antagonist. This means it works to block the action of particular chemicals known as leukotrienes, which are naturally occurring “inflammatory mediators” produced by the body’s own immune system. In asthma sufferers, there are particular leukotrienes which are key triggers in episodes. The leukotrienes that Singular targets are primarily found in the lungs. The drug acts to suppress the leukotrienes so that they will not trigger a cascading effect of inflammation and bronchoconstriction (wheezing and shortness of breath) in asthmatic patients.
What are the Approved Uses?
Singular has been approved for the chronic treatment of asthma, exercise-induced bronchoconstriction (EIB), and relief of symptoms associated with allergic rhinitis – including seasonal allergic rhinitis (SAR) and perennial allergic rhinitis (PAR).
Production Anecdotes / History
Singulair was developed by a global pharmaceutical giant, Merck & Co. in their laboratories in Montreal, Canada. The drug was approved for its currently prescribed use in 1998. The patent for Singulair expired in 2012 and several generic varieties are now on the market.
Precautions
General Precautions
Singulair is not an emergency inhaler and is not considered an “emergency response” for the reversal of an asthma attack. Patients on Singulair who are susceptible to acute asthmatic episodes should have appropriate rescue medications available in addition to Singulair.
Neuropsychiatric Events
Singulair has long carried a warning that it has been linked with an increased risk for “agitation, depression, sleeping problems, and suicidal thoughts and actions. In March 2020, the FDA elevated this warning to its strongest level – a “black box” on the prescribing label. This new warning advises physicians, pharmacists, and other healthcare providers to avoid prescribing Singulair for patients with mild symptoms. In addition to the black box warning, patients will get a special “medication guide” which outlines potential risks.
Systemic Eosinophilia
This drug has had reports of systemic eosinophilia presenting consistent with Churg-Strauss syndrome.
Long-Term Use Considerations
Patients taking Singulair should be regularly monitored for mood or behavior changes, including suicidal thinking or behavior. Additionally, patients should alert their physician in case of neuropsychiatric issues.
Drug Interactions
Patients prescribed Singulair should advise their physician if they are also taking drugs containing phenobarbital or rifampin.
Long Term Side Effects
Surveys and reporting on Singulair have reported neuropsychiatric events in adults, teenagers, and pediatric patients. The events noted include:
- Anxiety
- Depression
- Aggressiveness
- Agitation
- Attention and Memory Impairment
- Sleeping Disorders (insomnia, somnambulism, dream anomalies)
- Seizures
- Paresthesia
- Hypoesthesia
- Suicidal Thoughts and Behavior
FDA Warnings (History Of)
In 2008, after reports of suicide and other serious psychiatric events among users of Singulair were reported, the FDA issued its first warning requirement for its label. Following this first step, the FDA conducted focused “post-market surveillance” on Singulair looking for any additional evidence linking the drug to serious mental health issues. In 2019, the FDA presented its data on Singulair to an agency drug advisory committee, which assessed that the risks presented by Singulair outweigh its benefits for those patients with mild symptoms or where there is adequate alternate therapy. The FDA, acting on the advisory committee’s findings and recommendations announced in March 2020 that it would require Singulair to carry a specific “black box” warning on its labeling advising about the risk of neuropsychiatric events such as suicidal ideation and behavior.
Other Common Side Effects
Patients taking Singulair may experience any of the following:
- Headache
- Dizziness
- Abdominal Pain
- Sore Throat
- Rhinitis
- Diarrhea
- Wheezing
- Cough
- Rash
- Restlessness
- Tremor
- Nausea
Lawsuits
As of March 2020, attorneys across the United States have begun reviewing claims from potential litigants who believe they or a loved one has been harmed by taking Singulair. At the moment there are no class-action lawsuits or multi-district litigation (MDL) involving Singulair. This is likey to change, however, as more injured parties come forward in light of the FDA’s required black box addition to Singulair’s labeling.
Sources Cited (10)
1) “FDA: Singulair to Get “Black Box” Warning” https://www.physiciansweekly.com/fda-singulair-to-get-black-box-warning/
2) “Montelukast” https://medlineplus.gov/druginfo/meds/a600014.html
3) “What Is Montelukast?” https://www.medicinenet.com/montelukast/article.htm#what_is_montelukast_and_how_does_it_work_mechanism_of_action
4) “FDA Requires Stronger Warning About Risk of Neuropsychiatric Events Associated with Asthma and Allergy Medication Singulair and Generic Montelukast” https://www.fda.gov/news-events/press-announcements/fda-requires-stronger-warning-about-risk-neuropsychiatric-events-associated-asthma-and-allergy
5) “What Is Singulair?” https://www.everydayhealth.com/drugs/singulair
6) “U.S. National Library of Medicine|National Institutes of Health: Singulair (montelukast)” https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=10cd5ca5-6f8b-417c-af11-a2054a2dde34
7) “Tips for Taking Singulair and Avoiding Common Side Effects” https://www.goodrx.com/blog/singulair-side-effects-and-tips-to-avoid-them/
8) “Merck: Singulair Label” https://www.merck.com/product/usa/pi_circulars/s/singulair/singulair_pi.pdf
9) “Black Boxes: Health Warning or Profit Warning?” https://www.kevinmd.com/blog/2020/02/black-boxes-health-warning-or-profit-warning.html
10) “National Center for Biotechnology Information|National Institutes of Health: Montelukast” https://www.ncbi.nlm.nih.gov/books/NBK459301/
Tracy Everhart
Tracy Everhart is the Editor for Drug Law Journal. A highly-trained and certified medical professional, Tracy is also an accomplished medical writer. After spending years on the front lines of the medical profession, Tracy now devotes her expertise and skills to researching and reporting on new drugs and devices that enter the market, as well as their side-effects and the real-life stories involved. Prior to joining Drug Law Journal, Tracy wrote for benchmark online healthcare resources focused on families and, in particular, women’s health issues. Tracy holds post-graduate degrees from both the American College of Healthcare Sciences and the Yale School of Nursing. She is also a graduate of both Hampshire College, where she studied microbiology and the University of South Carolina school of nursing.
