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Singulair Side Effects

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According to allegations raised in a recently filed lawsuit, Singulair side effects caused a boy to suffer suicidal thoughts and a host of other psychiatric problems after using Merck’s asthma medication.

Stephanie Hammer filed the complaint last month on behalf of herself and her minor son, identified only as R.S.B., in the U.S. District Court for the Eastern District of Wisconsin. The lawsuit came several months after the FDA required Merck to place a black box warning on the asthma treatment due to neuropsychiatric side effects.

Singulair (montelukast) belongs to a class of drugs known as selective leukotriene receptor antagonists. It is a pill taken orally once a day to treat asthma, exercise induced asthma and seasonal allergies. Singulair is recommended and prescribed regularly for both children and adults.

However, the FDA issued a drug safety communication in March, announcing that the strongest label warning possible will be required for Singulair, featuring information in a prominent “black box” that includes data from a new review of an observational study, as well as ongoing adverse event reports involving mental side effects, including suicidal behaviors.

Singulair Side Effects | McKay Law
Parents United for Pharmaceutical Safety and Accountability ( created this poster of Singulair/Montelukast side effects based on those listed on the US label.

According to the lawsuit, R.S.B., of Wisconsin, was prescribed Singulair to treat his asthma and hay fever symptoms in December 2010, and used the medication until August 2012. The lawsuit claims that, as a result of his Singulair use, R.S.B. was admitted to a psychiatric care facility due to suicidal and homicidal thoughts. He was subsequently diagnosed with major depressive disorder, anxiety disorder, obsessive-compulsive disorder, homicidal thoughts and other psychiatric disorders.

“Singulair causes a decrease in neuronal proliferation (nerve growth) in the hippocampal neurogenic zone (part of the brain largely involved in things from short-term memory to long-term memory, and spatial memory),” the lawsuit explains. “In short, giving Singulair to healthy children can delay their nerve growth in the part of the brain that is most important to short-term memory, long-term memory and special memory. Furthermore, alterations in the hippocamus have been linked to a variety of cognitive pathologies such as anxiety, depression, addiction and neurodegenerative diseases such as Parkinson’s.”

Hammer and her son’s lawsuit presents claims of design defect, failure to warn, negligence, and breach of warranty. They seek both compensatory and punitive damages.

The FDA first required warnings about behavioral and suicide side effects of Singulair in 2009. However, the March warning indicated the agency continued to receive data on the problems, both from an observational study using data from the Sentinel Distributed Database, as well as ongoing reports submitted to the FDA Adverse Event Reporting System (FAERS). The agency first presented its findings at an advisory committee meeting in September 2019.

The FDA identified 82 cases of “completed suicide” linked to Singulair use at that time. The agency indicated that 45 of those cases involved patients older than 17 years old, 19 cases involved patients 17 years old or younger, and 18 cases where no age was indicated.

According to the lawsuit, about 9.3 million patients received Singulair prescriptions in 2018, with 2.3 million of those given to children under the age of 17.

Singulair Side Effects

A wide range of adverse mental health symptoms have reportedly been experienced by Singulair users. These include:

  • Suicidal thoughts, potentially escalating to suicidal ideation and attempted suicide
  • Insomnia
  • Nightmares
  • Anxiety
  • Increased aggression
  • Restlessness
  • Irritability
  • Memory issues
  • Sleepwalking
  • Depression
  • Lack of focus and reduced ability to concentrate
  • Body tremors

If you or a loved one has experienced any of these symptoms, you may have grounds for a lawsuit against the drug manufacturer.

Free Consultation with Singulair Lawsuit Lawyers

Mckay Law is eager to boldly fight and protect anyone who may be a victim of Merck & Co. Singulair’s mental health symptoms! Free consultation 24/7 with McKay Law’s Singulair lawsuit lawyers
Call us today or submit your case.

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