Singulair Side Effects Linked to Risk of Nightmares, Depression, Aggressive Behavior: Study

  • Written by: Martha Garcia

The findings of a new study highlight the potential side effects of Singulair, indicating that the popular asthma drug may increase an individual’s chance of suffering from nightmares, depression and aggressive behavior. 

Both adults and children who took Singulair (montelukast) frequently reported experiencing neurological side effects, according to research published in the medical journal Pharmacology Research & Perspectives on September 20.

The retrospective study looked at adverse drug reactions among both children and adults taking Singulair in the Netherlands. Reactions were reported to both the Netherlands Pharmacovigilance Center Lareb database and the World Health Organization Global database, VigiBase, until 2016.

Overall, depression was the most frequently reported Singulair side effect for both children and adults, as reported to the worldwide VigiBase. In only children, aggression was the most common side effect reported in VigiBase.

Headaches were reported most frequently to the Netherlands Pharmacovigilance Center database. Nightmares were often reported for both children and adults to both the Dutch and WHO worldwide database.

In 2013, the consumer watchdog group Public Citizen placed Singular on it’s “Do Not Use” list, highlighting the risk of nightmares, hallucinations, insomnia and other psychiatric problems, especially among children. The group also noted that the benefits of Singulair were minimal.

Among other side effects, the Dutch database indicated eight patients reported allergic granulomatous angiitis; whereas 563 reported the condition in the WHO VigiBase.

“These data demonstrate that montelukast is associated with neuropsychiatric adverse drug reactions such as depression and aggression,” the researchers concluded.

In 2009 the FDA ordered a Singulair warning label update, adding information about reports of suicide, suicidal thinking, aggression and other neuropsychiatric side effects.

Singulair 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. It is one of the top selling medications in the U.S., with sales of $3.5 billion in 2008.

Singulair is recommended and prescribed regularly for both children and adults. The manufacturer indicates common side effects include stomach pain, diarrhea, fever, flu-like symptoms, stuffy nose, sinus pain or headache. Other side effects may include skin rashes, ear pain or swelling, severe tingling, and changes in mood or behavior.

The effectiveness of Singulair is commonly debated. Some doctors believe it is not an effective treatment for asthma and other medications should be used instead, especially considering the widespread side effects.

A 2014 study indicated Singular did not prevent wheezing episodes among children who took the medication. In fact, children saw no improvement in wheezing episodes, compared to children who did not take the drug.

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  1. Lynne Reply

    This is not new news,there is a whole community of us on a facebook group,who for the last 9 years have been our only source of support and understanding,that these side effects are not rare,and can seemingly cause long lasting damage.Join our group and read in real time the heartbreak this drug has caused so many children and adults.Mostly the kids,what about the kids.This drug is know being trialed for serious brain diseases in adults,and yet daily a doc writes a script to a parent for their young child,without even one study on what it might do to the developing brain.My child took this drug for 3 years from age 11 to 15 and since then i have done as much as i can to help see what happened to him does not happen to another,but our hands are tied to some degree by big pharma the fda and the law itself,but believe me when i say children continue to suffer

  2. Julia Reply

    Lynn, what is the name of your Facebook group?

  3. Tekia Reply

    My child started bed wetting and began having an inability to control her bladder. She would literally run to the bathroom and urinate on the floor. The smell of medicine reeked from her pores and her urine became dark as well. When I brought this to her physicians attention they tried to have me brainstorm other reasons but it’s clearly a side effect that they didn’t tell me about and although my child drinks plenty of water and has been off the meds for over a week it’s only mildly better)the smell) she still sets. I pray it’s not a long term effect or that no liver/kidney damage was caused. I feel like they are trying to cover something up.

  4. Stephanie Reply

    My 7 year old son has severe non-verbal Autism and Intellectual Disability. He also has horrid seasonal allergies and what we suspect to be intermittent/mild asthma. His doctor prescribed montelukast to help manage those symptoms. My son took it for a month and it’s the worst parenting decision I ever made. He went from being a child with pretty mild behavior and ZERO self injurious behaviors to completely inconsolable. He started hurting himself, banging his head, hitting others, crying non stop, developed sleep disturbances and TREMORS. He is non verbal. He couldn’t tell me how he was feeling. I am ashamed to say that it took me a month to figure out that it was the montelukast prescribed for his allergies causing this devastating upset in his life. I am so angry. I feel like given his neurological and communicative disabilities I should have been made more aware of the side effects. We have been off the med for about 3 weeks and I have not yet seen a change in his behavior but the tremors have gone away.

  5. Katie Reply

    Hi, the Facebook support group is
    Montelukast (Singulair) Side Effects Support and Discussion Group

  6. Victoria Reply

    I seek a lawyer who is ready to help me sue Merck Pharmaceuticals for injuries to my brain that are most likely permanent. I took Singulair for ten month’s, in 2013, for allergies and I have suffered a profound reduction in my ability to function. For the first two years after I stopped using it, (the statute of limitation cannot apply since I was still extremely impaired and unable to advocate for myself). I have lost FIVE part time jobs since taking Singular.
    I was diagnosed and began treatment ifor depression around 1997. Never felt suicidal.
    Now, realizing I will never restore to my former self, feeling disconnected from everyone, and having no support or guidance from doctors or family, now I do experience suicidal thought. And now, for the past 6 months, I have developed severe carpal tunnel syndrome which has left me with numbness tingling pain and loss of dexterity.

  7. Victoria Reply

    I am seeking damages for what appears to be permanent brain damage, pain and suffering and loss of ability to support myself. I have two doctors who have known me for at least 20 years. I saw a neurologist soon after stopping Singular while Iwas worst. My PCP recently referred me back to the same neurologist for additional testing on my brain. I received a CAT SCAN, (an EEG or EKG, I get those two confused) and other types of brain studies. I was advised half of my hippocampus is mishapen after the first CAT SCAN.

  8. Judy Reply

    My 15 year old grandson has been taking this for at least 2 years and in September was hospitalized for a week due to suicidal thoughts and self harm.

  9. Kristin Reply

    My daughter is 10 and late last year she was hospitalized for depression and suicidal thoughts. She missed a lot of school and hasn’t been able to recover from this. I would love to speak to a lawyer about what she has gone through.

  10. Michelle Reply

    My son used this from toddler to 14 with a period of non use in between He had terrible night terrors when he was little that were brushed off as common & later on developed severe anxiety & panic attacks He’s been out of school & basically society ever since. We he stopped for awhile in between toddler & preteen/teen he was happier, outgoing & talkative

    Now I know what really happened to my child !! I’m pissed !!

  11. DL Reply

    My husband took this for 2 months and began having severe nightmares. Odd symptoms began. Memory loss, depression, agitation, confusion. I believed the nightmares were caused by this so I stopped giving it to him. Then within 2 weeks psychosis set in. Horrible day to day struggle to manage his sudden issues. Doctors were completely baffled by these sudden out of the blue symptoms. After finding comments like these I now realize it was the Singulair. I’m both relieved and extremely saddened that this caused his suffering. Our entire family has been altered by the effects of this drug on the head of our family. Better but not completely free of symptoms- I want to band with others to stop this from happening to anyone else.

  12. Em Reply

    Been taking singular for 10 YEARS. I’m 21 now. I have struggled with depression, aggressive attitudes, insomnia, and nightmares for years. Still struggle with nightmares as an ADULT. Saw a psychiatrist for depression. Meds they gave me DIDNT help. I’m angry that this warning came out only now.

  13. Marcianne Reply

    I took generic Singulair from 11/18 to 4/19 and developed worsening symptoms of headaches, depression, tics, and anxiety. Now after stopping the medication the tics are worse than ever.

  14. Kimberly Reply

    My 13 year old was put on singular for her asthma and allergies. She was a happy loving soul then she started cutting, not only her arms but her legs. I took her to the behavioral hospital and they kept her for 5 days. It was the most hardest thing to do. No one said anything about it might be the cause they continued to give it to her. They diagnosed her with depression, and 2 other things. After she came home she was still not herself. March 4th is when I got a notification in a news app. The FDA put out a statement about singular and the effects. I took my daughter off that day and she is almost back to herself. That was a long and painful 5/6 months. I really hope they have a class action lawsuit against whoever it needs to be against because they should not be giving it to people if that’s the effect it has on people.

  15. Sabrina Reply

    I was on singulair 10mg from ages 10-20. After starting medication became very aggressively angry, mood swings, irritable, depressed, anxiety. I stopped taking singulair at 20 when I decided I would finally go through the withdrawal of stopping (headaches, dizziness, unable to get out of bed if I missed a pill for the day) that I never wanted to stop and experience so I could finally be done trying to get a doctor to prescribe it to me since I had originally been prescribed by an allergist I had seen from ages 10-13 and my pediatrician. Around the time i stopped taking singulair, for the first time I read about the fda requiring disclosure of the psych symptoms and un effectiveness of the drug to treat asthma in relation to the overwhelming side effects. I am now three years off singulair and I have dealt with 3 years of deep depression (causing weight gain, weight loss, suicidal thoughts) continuation of aggression, irritability, difficulty sleeping, attention problems, anxiety. I fear that taking this drug during 10 years of my crucial development and growth as a child on an adult dosage is leaving forever permanent damage on my heath and wellbeing. I just recently have been experiencing an increase in symptoms and remembered my findings from a few years ago and found this forum of other people who have similar symptoms and experience.

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