Singulair and seasonal allergies

I just started Singulair about a month ago. Before I started taking the tablets I remember hearing some negative information on the news about the medicine. I found this web site and read about all the side effects before taking my first tablet. Even though there was so much negative information I thought I would give the medicine a try anyway. I have always been in good health and only needed this medicine for seasonal allergies. Part of me said "I know the side effects wont affect me!" Well I was WRONG! I have had the worst nightmares!!!

The nightmares started the first night I started taking Singulair. I continued taking the medicine hoping the nightmares would pass. Well, they have only got worse. However, last night was horrible. Not only did I have my nightly nightmares I had a hallucination! It started when I heard my 2 year old son wake up. He first opened his bedroom door then drank some water that was on his night stand, then was on his way over to my room. I got up to put him back in bed just to find out his bedroom door was closed and he was sound asleep in his bed. I haven't had any other side effects, but I think this is a good enough reason to stop taking the medicine. Does anyone have any other suggestions for another allergy medicine I can take. I've already tried Nasonex and Flonase they don't work nearly as good as Singulair. Any suggestions would be great thanks!

In response to Wewe's post, I've been wondering the same thing. Since taking my daughter off Singular almost 2 months ago, I'm seeing a different almost typical kid. Four years ago about 2 months after starting Singular my daughter was diagnosed with anxiety. As her condition got worse she was diagnosed with depression. We started to see OCD and tics so they were added as a diagnosis It was determined that it was related to strep infections so she was diagnosed with PANDAS. She was started on Zoloft and klonidine. The Zoloft made her worse. Her fears of hurting herself got so intrusive she was hospitalized. Her cholesterol was high too. The Zoloft was discontinued and Prozac was started. She's had therapy all 4 years. She also neede physical therapy due to muscle and joint pain. Now she's doing better, off Singular. Does she really have PANDAS, OCD? I don't know. She's still on Prozac, we just did a slight decrease this week. Is this medication the trigger for underlying conditions. Learned behaviors can be unlearned, but are there lasting physical effects? If a gene has been turned on, can it be turned off? I wish we knew the answers to help all of our kids.

My 10 year old son has taken Singulair on and off since he was 5 years old and has been on it for the past 3.5 years. My son at an early age was affected by a bad marriage and then the divorce when he was 5 yrs old. So we always suspected that his behavior issues were caused by this and I had done everything I possibly could to give them the help he needed to get over and through his issues. He was held back his first year of Kindergarden and during his second year midstream he was placed in a special class for behavioral problem children. Nothing ever seemed to help him, everytime we would see some progress and encouragement we were always blind sighted by a behavior that was always worse. Two steps forward and them 5 steps backwards. I always knew that his problems would never get better overnight so I just kept on going. He was diagnosed with ADHD but because he has some ticking issues I had to put him on Strattera which was did not do a thing for him. I always described him as my Dr. Jeckyll/ Mr. Hyde child. He could be really good and sit still and behave but I think he had to try really hard to do so. He eventually was always overpower by the impulse to show negative behaviors. Defiant, extremely impulsive, always negative and completely miserable all the time. He also went through phases of compulsions. There was always a compulsion of the month- germs, bathroom habits, noises, repetitive words. He hated school and always complained of a stomach ache which i thought he was always faking to get out of school. He had confrontations in school everyday for most of the day. I often thought some of this was because of being tired all the time. We had battled over bedtime every single night. He was terrified to go to bed alone, I tried everything to get him to sleep alone. I wore myself out falling asleep next to him, I would then go to my own bed only to be up with him half the night going back and forth. I gave in many a night and slept with him just so we could get a good nights sleep. At age 8.5 I finally got him to go to sleep alone but the lights haf to be on and he has to know that I am still awake before he will fall asleep. He would always say he didn't want to go to sleep because when he does he has bad thoughts about me and people that he loves. He always had an extremely hard time excepting the word "no"- he would flip out and hit his head with whatever was handy, throw things, break things, scream holler etc. It would take hours to get over it. When he did he would be very remorseful and lovable. He was always in turmoil. Finally in February of this year, this graduated to a new level where he would want to just kill himself and would actually go and pull a knife out of the drawer and just shake with anger as he held the knife to his throat. I was terrified although i really didn't think he was going to harm himself he just wanted to scare me. Then at the end of March when i first heard the news about the possible side effects of Singulair, I had only heard about the suicide effect. Oh great just what I needed was this medicine causing him to do that. The doctor was thinking about taking him off if this summer because he wanted to see if he out grew his seasonal allergies so I took him off immediately. Well I had no idea about the other side effects until my son turned into a completely different kid. School noticed a huge difference in him! His grades went up, his is able to control his behavior, he is happy he is NORMAL. I never suspected this drug as the culprit due to the timing of taking it. Our lives have changed completely. When i first found this site, it seemed as though some of the parents were writing about my child. It is amazing. My son still has some old habits to break but overall he is a wonderful and normal 10 year old boy. He did not outgrow his seasonal allergies but Allegra seems to help in through it. I get so angry- his whole early childhood was ruined by this medicine. He is a labled kid in our school system. This whole experience has opened up my eyes. Thank you for letting me share my story.

I just started using Singulair a few days ago. I am 54 years old and just started coughing at night only. I would be fine during the day and then never failed, at night I started to cough keeping me awake. I was given antibiotics, narcotic cough syrups but it only helped temporarily and then I went back to coughing nights only again. So as I mentioned, I started taking Singulair a few days ago because my physician thinks I have developed allergies and Singulair is noted to help night coughs. It is helping my night coughs but I still cough a few times at night and now I cough quite a few times in the day when I never use to cough in the daytime. Wondering if Singulair is worth taking as the symptoms are becoming opposite? I hate taking drugs and don't know if I should find a safer alternative? Help, anyone? Thank you

I am finally writing after reading these posts since the end of April. That is when I took my 11 year old son off singulair, in an act of desperation. He has been on singulair on and off for about five years for seasonal allergies. He started again in mid-March so it could get into his system, before the allergies started. Immediately thereafter his behavior changed. He was arguing on a daily basis. He would hit, kick or trip me when he was angry. He was starting to destroy things in anger. He seemed to be fueled by anger. It was affecting the whole family. He was starting fights with his younger brother, my husband's heart was palpitating and I was crying every day. I heard about Singulair side effects and looked it up. I saw that it caused behavioral changes and out of desperation, took him off, not knowing what to expect. We had three days of total peace, then on the fourth day another outburst. Then my son told me he had taken a singulair the night before. That was it. I threw every pill in the garbage. He no longers acts like that. It's been almost two months so I am convinced it was the Singulair. By the way, he always complained of headaches, stomach aches and would scream in his sleep. Who knew - it was the singulair all along.

My nine year old daughter has been on Singulair for just over a month because of seasonal allergies. Early this morning she woke up with a terrible nose bleed. She has never had a nose bleed in her life before today! Could this be because of the Singulair?

This is my story. My daughter 14, the most precious child ever born. She has a wonderful disposition always happy, loving, and determined to succeed in whatever she does. She just brightens everyone’s world.
She suffers from severe seasonal allergies and mild asthma. She takes approximately seven allergy/asthma medicines a day during peak season. Over the past two years she has been taking Singular as one of her medicines. Being 14, sick of taking medicine she would not take the Singular on a regular basis. Approximately four months ago “MOM” says, if you take nothing else take your Singular it will work both for the seasonal allergies and your asthma. She has been taking this regularly four the past four months.
She became paranoid, she became a compulsive eater and bites the skin on her fingers. She would eat and chew on her fingers at the same time, until she choked. She had so much anger, she could not even go to the mall without temper tantrums.(As a child she never had any tantrums ) Always afraid. Severe depression set in. She would cry at a moments notice. She would say, I have a very sad life, sad very sad, nothing makes me like this, I’m just sad. She felt she should go live with the homeless people. I asked her why, she didn’t know, she felt maybe that’s where she belonged. Nightmares and sleepless nights.
She needs help quickly. Before calling the Doctor, I went on the internet and entered Singular and depression and I found 1900 entries, all people telling me what I was experiencing. Could this possibly be the answer for us? I called her Dr and told him what I thought, he said he has never had anyone that this has happened to. He hoped it was the answer, but really didn’t think is. He said if it wasn’t the answer she would need therapy, mood stabilizer and Prozac.

Its day four off Singular, she smiling, no tears today, no temper tantrums, looking forward to school next week, wants to play volleyball next year, singing in the car,
I hear that happy voice again.(Hi, Mommy!!!!!!) Every once in a while a glaze comes over her face. She isn’t a 100% back, but I know it is coming.

To all the people that don’t have the happy ending, I will pray for you and hold you in my heart forever.

June 2, 2008

My son, Wilson, is a bright, easy-going, athletic 12 year old who has a history of asthma and allergies. After several asthmatic episodes from age one year to about four, he was prescribed Singulair. The asthma triggers seemed to be change of season or congestion from a cold, but not from exercise or physical exertion. As I recall, his asthmatic episodes seemed to decrease after he was on 5-10 mg of Singulair, and even more so with each passing year. Over the years, of my three sons, Wilson was the one to catch any virus that came around and missed more school time than both of his brothers combined. Often, he was the only one to get sick from a virus, which never passed to anyone else in the family.
About five years ago, Wilson started complaining of stomach aches. He was tested and was prescribed Prevacid on and off since then with varying success. In the last couple of years, headaches would come and go. He was re-tested for allergies and blood work with no conclusive results. About 2-3 years ago he would complain that he “felt funny…like he needed to do something.” Further conversations revealed that he was expressing anxiety. He’s a good student, has lots of friends at school, and is popular among his sports team mates. Occasionally, a teacher here and there over the last couple of years would note that he did not participate enough in class, or did not appear to be attentive. We thought perhaps he is shy. Still his good behavior, agreeable personality and diligence otherwise earned him good grades overall. He loves school and was very unhappy having to stay home when he was sick.
This past winter, he seemed to catch a virus about once every month and a half which caused him to miss 2-3 days of school. Headaches and stomach aches were common with each illness (sometimes nausea), and sometimes these same symptoms when he was not ill. He would only complain when they were prolonged or significant. Trips to the doctor did not result in anything conclusive. Again, Wilson was only too happy once he returned to school.
He claims that sometimes in school he feels like he’s in a fog and has difficulty concentrating. He gets plenty of sleep and sometimes sleeps up to ten hours during the weekend. We attributed it to adolescence and a busy schedule. He claims that this year is the easiest for him at school, and his social life with his friends is very active. His friends’ parents like him and find him to be an agreeable child. Other adults mistake his sometime mumbling answers and lack of eye contact rude. We concluded that he is just shy. He is the most hyper of his brothers, and has difficulty sitting still and constantly exclaims that he’s bored. We chalked it up to being an active boy. His grades are good in school and we never get complaints about bad behavior.
The last illness started a week ago, and he’s still out of school. The doctor said he had no significant allergy symptoms, other bacterial infections, and his blood work all returned with normal results for white blood counts, liver and kidney functioning and anemia. He can’t return to school because of his constant headaches (which cause pain in different parts of his head), nausea, constant stomach aches, no matter what he eats, and feelings of anxiety, mostly in the evening hours. He’s also complaining of dizziness, leg cramps and other muscle soreness. The notable difference in this illness is the anxiety. My husband and I take turns staying home with him, but if we left him alone for a half an hour at a time while the other was in route picking up a sibling, he became very anxious. In the past, he seemed to enjoy some alone time at home so he could play his computer games. He also becomes easily dizzy with shooting pains in his muscles. The doctor said that viruses can manifest themselves in later stages in the form of sore muscles. However, he was concerned about Wilson’s feelings of anxiety. The anxiety had not been as prevalent in prior illnesses. I finally signed onto the internet reading all the stories about other parent’s observations of their children on Singulair. My husband cautioned me about “internet diagnosing” with symptoms and stories that can be easily taken out of context in hope of self-diagnosis. I’ve always thought that Wilson’s doctors have had good judgment. Both my primary physician and allergist don’t think that Singulair has caused these symptoms, but agreed to take him off as long as we monitored any effect on his asthma.
I don’t know what to think. I want the cause of these problems to be the Singulair, because it’s an easy answer. Today will be the first day he’s off the medication. He probably won’t go to school again tomorrow. We’ll wait and see what happens…

Sorry, I can't just walk away.

When you find patents or patent applications for certain purposes, then you know that your ideas are well founded. There are several patents for using an anti-malaria drug for asthma. I would bet that somebody had that idea all the way back to the 1960's. So it is very possibly no coincidence at all that a chloroquinoline or other quinoline ring would be part of montelukast's chemical structure.

Here is one of the patents.

******

It is well known that quinoline rings can be toxic to some people even very rapidly. As in this very extreme example.
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PEDIATRICS Vol. 27 No. 1 January 1961, pp. 95-102 This Article

FATAL ACUTE CHLOROQUINE POISONING IN CHILDREN
Howard M. Cann M.D.1 and Henry L. Verhulst M.S.1

1 National Clearinghouse for Poison Control Centers, Accident Prevention Program, Public Health Service, U. S. Department of Health, Education, and Welfare
Four cases of acute chloroquine poisoning in children are presented. In three instances death occurred within 2 hours of ingestion of larger than therapeutic amounts of the drug. The rapid occurrence of death in acute chloroquine poisoning is probably explained by complete and rapid absorption of the drug from the gastrointestinal tract resulting in high blood concentrations which depress vasomotor function and respiration. Cardiac arrest follows and may be caused by the direct myocardial action of chloroquine, to anoxia, or to both. The similarity of the manifestations of acute chloroquine poisoning and those of acute quinine and quinidine poisoning suggests that acute toxicity may be attributed to the quinoline ring portion of these drugs.

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I don't think that we are seeing extreme examples. But we may be seeing less extreme immediate reactions or reactions where the toxicity builds up over time.

Quinoline rings are know to cause neurotoxicity. There are theories about how that happens. One of the theories is about blocking connexins which are gap junction proteins in the brains.

I don't know how montelukast could be breaking up so that it causes toxicity. Or if the problem is the how rapidly the liver enzymes can metabolize it. But there is plenty, plenty, plenty of clinical evidence that there is a quinoline ring culprit somewhere in the picture. Or some by-product of that causing problems.

Somehow it was decided that montelukast did not have the safety issues that the other drugs in the same category have. See this.

"The starting point in the development of montelukast appears to be a quinoline-containing structure, likely identified as a weak random screening lead (Figure 3). The Merck group hypothesized that this molecule was mimicking the olefin backbone of cysLTs, and that the addition of mimics for the acid and peptide regions of LTD4, might improve its potency. As a first step, the dithioacetal linkage first seen in some SmithKline compounds was incorporated; this led to a compound with greatly increased in vitro potency but poor oral bioavailability. When one of the carboxylic acids was replaced by an amide, forming MK-571, the new antagonist had even greater potency and good efficacy following oral administration. The enantiomers were resolved to yield MK-679 (verlukast), a compound with better clinical effects than MK-571, but whose clinical development was stopped for safety reasons. Further structure-activity relationship studies led to the development of montelukast (16), an antagonist that appears free of the safety concerns plaguing earlier members of this series."

If we can find out why the earlier versions were not safe and how they thought fixed it, then maybe we can find out what is going on with the quinoline ring in some people.

I would be very surprised if the FDA will address our concerns. Why does it always seem like they wait for enough people to die like in Vioxx? Wasn't Vioxx responsible for thousands of deaths?

We have all been saying that our issues regard not being informed about all of the possible side effects. And, we know that Singulair works well for some people. Nobody wants to take a good drug away from those for which it probably performs miracles. People who have toxic side effects have a right to know up front.

My observations about montelukast's chemical structure are either general or not quite 100% correct or could be quite vague - so forgive me. I do not claim to be good at organic chemistry. But from doing a little work, I have come up with some observations.

1. It would seem to me that montelukast might work quite well for people who have developed mold category related asthma. I observed that chloroquinolin, a component of montelukast, is a good fungicide effective against Aspergillus, Alternaria, Cladosporium, Penicillium and Candida. Dust mites can only digest if helped by aspergillus so they go into the mold category. Molds produce millions of spores so anyone who lives in contact with mold would be chronically sick from their presence. Then people get hypersensitized to that.

I am probably wrong but I could imagine that montelukast is: 1) a ligand that binds to an empty cysLT1 receptor for a period of time 2) 7-chloroquinolin-2-yl which either acts intact or breaks down into a quinoline fungicide so that it kills the chronic mold/fungus infection and 3) a sulphur/methyl anti-inflammatory component that tells the t-cells that they are not needed so they will die. Wow, that would be great for mold asthma if it was completely non-toxic. It would be also great under controlled circumstances for many people who are mold-miserable. If I am wrong, I better go out into my garage and start inventing such a drug.

This is my visualization to try to explain the side effects of neurotoxicity. So adverse reactions could be to the quinoline component as an allergic reaction or dose related so that it just built up to a toxic level over time. There are many signs that t-cell populations are significantly reduced by montelukast. The fact that the Italians can do it in the test tube might be that it's a chemical component of montelukast designed to cause the t-cells to die.

Montelukast is a large molecule so Artie says it cannot penetrate the blood brain barrier. That would be an argument if nobody was complaining about neuro-psychiatric side effects. The neuro-psychiatric side effects are identical to quinoline and quinolones. When I read about Lariam, it just sounds like a more extreme version of Singulair side effects. Chloroquinolins were used before they invented Lariam, which is stronger. The malaria Plasmodiums became immune. Hallucinations, anxiety, depression, suicidal thoughts are completely consistent in all of the quinoline/quinolones. If montelukast breaks into sub-molecules then quinolines easily penetrate the blood brain barrier.

I find clinical evidence that montelukast may act as more than more molecule. And, that there is a rational for the existence of the chloroquinolin and evidence that it may be the source of toxicity.

I am glad to risk being called crazy. That is what the internet is for. We can present our ideas and discuss. So, just take this with a grain of salt. If I am close to the truth, this post will find it's proper home.

Effective after two weeks for some people - not effective for others. Side effects for some people - others do not report side effects. So why does Merck have to grow their market before they have any idea what's going on?

This isn't a big group of people in the study but it makes sense from what we are reading here. These researchers did examine the mast cells. We need to know about mast cells (while suppressed by montelukast) on a longer term basis.

J Asthma. 2008 Apr;45(3):243-50. Links
The efficacy of montelukast and airway mast cell profiles in patients with cough variant asthma.Kawai S, Baba K, Matsubara A, Shiono H, Okada T, Yamaguchi E.
Division of Respiratory Medicine and Allergology, Department of Internal Medicine, Aichi Medical University School of Medicine, Aichi, Japan.

Background. Cough variant asthma (CVA) is characterized by chronic cough without apparent wheezing; its pathophysiology is considered to be similar to that of classic asthma. Objective. The clinical effects of montelukast, a cysteinyl-leukotriene receptor antagonist, on cough variant asthma were assessed, and the activation profile of airway mast cells was examined. Methods. Montelukast (10 mg/day) was given orally to 36 CVA patients (25 women and 11 men; median age, 37.5 years). Before treatment, the patients' bronchial mucosa underwent a biopsy with a fiberoptic bronchoscope. The biopsy specimens were double stained with anti-CD63 antibody and anti-human tryptase antibody. Results. After 2 weeks of montelukast treatment, cough symptoms improved in 22 patients (the effective group) but did not improve in 14 patients (the ineffective group); in the ineffective group, the symptoms disappeared 2 weeks after they were switched to fluticasone propionate (400 mug/day) inhalation therapy. In the effective group, the time interval from the onset of symptoms to the initiation of treatment was significantly shorter than in the ineffective group. The bronchial mucosa biopsy specimens showed that the proportion of CD63-positive cells in tryptase-positive mast cells was significantly higher in the effective group than in the ineffective group; although the total numbers of mast cells were not different between the two groups. Conclusion. There is a subgroup of CVA patients in whom leukotrienes are closely involved in the pathogenesis of their chronic cough; activation of airway mast cells may be an essential feature in these patients.

PMID: 18415834

One of the most important questions we should be asking as parents is:

How does Singulair - a leukotriene receptor antagonist (blocks the receptors) affect the normal function of the mast cell?

The mast cell is the FRONT LINE DEFENSE against invading micro-organisms. When Singulair was invented, there was limited knowledge regarding the mechanisms by which the mast cell performed it's function. In my opinion, the focus was very narrow - those interested zeroed in on how the leukotriene receptor performed a role in the cause of asthma attacks and how ashma attacks could be prevented. Well, that's good preventing asthma attacks. But what happens to the mast cell if that receptor is blocked on a long term basis. I am not suggesting that blocking the receptor is bad but what if the long term effect is different than what we are are lead to believe-which is this is a safe medication with no known long term effects. What if the leukotriene receptor was just blocked short term a week or two to allow the body to clean up the mess from the last attack?

I seriously question what is going on with all of these infections. Are they related to crippling the mast cell? Parents should be allowed to question. If Merck doesn't want to answer questions regarding what happens to the mast cell (including are the numbers of mast cell decreased on Singulair), then something really BIG is missing. If by any chance (unknown at the moment) that the mast cell is significantly changed and therapy by montelukast is proper on a short but not long term basis, so freakin' what if Singulair is not a huge money maker any more.

Parents deserve every answer possible when decisions regarding their child's growth and development is on the line. I hope that we get some answers.

Of course, what was there in 2002 were new questions-not necessarily answers about the mast cell. Did anybody apply this to Singulair studies?
May 2002

From Journal of Clinical Investigation

Pattern recognition receptors on mast cells
The Toll-like receptors (TLRs) fit the definition of pattern-recognition molecules, which were originally postulated to allow the innate immune system to detect the 'molecular signatures' of various infectious agents. Although the innate immune system has no memory, it shows a degree of specificity, in part because the various TLRs recognize different sets of pathogen-associated molecules. Dermal mast cells are usually associated, not with the innate immune system, but with atopic dermatitis, but Supajatura et al. have found that these cells also express TLRs. They report here that TLR4, which binds the gram-negative product lipopolysaccharide (LPS), and TLR2, which binds peptidoglycan (PGN) from gram-positive organisms like Staphylococcus aureus, induce distinct mast cell responses. Staphylococcus is known to exacerbate allergic dermatitis, but it has generally been thought to act by inducing antibacterial IgE's, which trigger mast cell degranulation by stimulating the IgE receptor. Interestingly, the authors show that the interaction between PGN and TLR2 can provoke mast cell degranulation directly, sidestepping the need for IgE receptor engagement.

I found this message board last night and until then, I thought my daughter was just bad. She is almost 3 and has been on Singulair for a little over a year. I have said on many occasions, "What happened to my sweet girl?" After the suicide and Singulair connection, my husband would joke and say that's why why our daughter is out of control. I finally decided to check into it and was amazed at the number of kids out there like my daughter. She is an emotional wreck! Her mood swings are something else. I have to walk on egg shells around her so not to upset her. For example, she will walk up to me smiling and give me a hug. When I hug her back, she screams at me and tells me to let her go or to stop touching her. When her brothers talk to her, she screams at them to stop talking to her. She has meltdowns numerous times a day. I am going to stop giving her Singulair as of today and hope that she will improve.

If anyone has any access to databases that can describe the history of drug licensing in other countries and whether Merck had to amend product statements, this is worth investigating. I do know that montelukast was at least not initially licensed for seasonal allergies in the United Kingdom when the FDA granted approval in the US. As of 2006, seasonal allergies were not on the approved listed in the UK.

More to add to the files:

Safety of leukotriene antagonists
United Kingdom — The Medicines Control Agency
has published a review of adverse drug reactions to
a new class of asthma drugs, leukotriene antagonists.
Zafirlukast and moltelukast, competitive cysteinyl
leukotriene type-1 receptor antagonists, were
both marketed for the first time in 1998.
Cysteinyl leukotrienes are inflammatory mediators
and potent constrictors of bronchial smooth muscle
that attract human eosinophils and cause airway
oedema, mucus hypersecretion and reduced
mucociliary clearance. By blocking this action, leukotriene
antagonists can improve respiratory function
and lessen symptoms in patients with asthma.
The pharmacological action of leukotrienes is quite
complex and varying side effects have been
reported. Zafirlukast inhibits the hepatic cytochrome
P4502C9, and interacts with warfarin, theophyllin,
terfenadine, acetylsalicylic acid and erythromycin.
Montelukast is metabolized by hepatic cytochrome
P450CYP3A4 and co-administration of such drugs
as phenytoin, phenobarbitone and rifampicin, which
induce this enzyme, result in a marked reduction in
plasma levels.
Side-effects identified during clinical trials were
headache, abdominal pain, nausea, diarrhoea,
gastro-enteritis, influenza, pharyngitis, sinusitis,
cough, nasal congestion, dizziness, fatigue and insomnia.
Since marketing of montelukast, 173 reports
of 317 suspected adverse drug reactions
have been received in the United Kingdom. These
include oedema (50), psychiatric reactions, including
including agitation/restlessness (15), allergy, including
anaphylaxis, angioedema and urticaria (10), chest
pain (7), tremor (5), mouth dryness (5), vertigo (4)
and arthralgia (3).
Reference: Current Problems in Pharmacovigilance,
Volume 24, August 1998.
https://www.who.ch/druginformation/vol12/12-4.pdf

Previously posted 8 year old son w/ suicidal ideation and depression...I'm seeing comments about "inattentive." I've been saying my son is ADD for years....How many of you saw this possible side effect? Off of Singulair for 14 days now....behavior unbelievably improved.

A two days off of singulair my son started with a sore throat and headache that didn't go away for 5 days., three days after that started he ran a low grade fever for two days. I've read about others who had the same thing happen, so if your just getting off the singulair you may feel like your getting sick.

I am starting a new post in the hopes that others will see what I am trying to say about the delayed reaction in those that took Singulair for allergies.

If it is consistent that Singulair does not stop allergy symptoms immediately, then the pathways that eventually stop allergy symptoms involve a change in the mast cell function, development and migration (or some combination).

I asked this question for a reason. Are allergy symptoms stopped immediatedly. My question below:

I have a question that will help me continuing looking for information. I can understand that in the case of asthma that Singulair would provide immediate relief. If it is used for seasonal allergies or other allergies without asthma, does it work right away or does it take a period of days or weeks to be effective? If it takes time, could you tell me how long it took in your situation?

My thinking was going in the right direction if the answer below is consistent of everyone or most.

about 2 hours ago on Apr 11, 2008 by catherineevans, #7045
My granddaughter was put on Singulair for allergy symptoms without asthma. Itching, red eyes, terrible congestion, etc. dark circles under her eyes all the time. When we first put her on this, we didn't see any consistent results for 2-3 weeks, then it seemed to 'kick in.' I don't know if this helps. By the way, she was 9, now she's almost 12 and was immediately taken off when this story came out 2 weeks ago.

Then after seeing one response, I gave my reason for asking.

I asked this question because I have a theory of how montelukast really works for allergies as compared to how it works for asthma.

Asthma is a hyper-sensitive state that gets going because the mast cell has a receptor (the leukotriene receptor that Singulair blocks) that sends a signal along a pathway that causes lung tissue to have that extreme response - the wheezing, the airway constriction.

On the mast cell is another receptor the histamine receptor that causes the secretions that make our noses runs and and stuff up. This is not the same immune response as the asthma response. When I saw a post that somebody's doctor said that Singulair is an anti-histamine, NO it is NOT.

So if Singulair does not block histamine immediately and your child's allergies did not go away immediately, then maybe Singulair is working through some other means such as changing normal mast cell homeostasis.
I know that this seems like "what does this mean?" I am really writing this hoping to God that there are people reading this site that know what I am talking about.

Thank you so much for responding. Your answer actually told me what I wanted to know and confirmed my hypothesis. More answers will help. I hope others respond.

PLEASE respond about the length of time that allergies disappeared if you took Singulair for allergies.

I have a question that will help me continuing looking for information. I can understand that in the case of asthma that Singulair would provide immediate relief. If it is used for seasonal allergies or other allergies without asthma, does it work right away or does it take a period of days or weeks to be effective? If it takes time, could you tell me how long it took in your situation.

UPDATE: Our nightmare with SINGULAIR has not ended! After reading "conerned citizens" report discussing the possiblility of Singulair causing asthma blew me away. My son was put on this drug for food allergies not asthma b/c they thought of his two anaphylaxsis episodes in 5 days. 1 food related the other unknown (maybe outdoor mold?) He had no prior issues with breathing.

He has been off of it for almost 2 weeks however over the last week he has slowly developed some breathing issues. After getting off of it, he still has his ear infection from the second day of being on it and last Friday after playing some basketball began to seem like he was winded so I brought him in. He was having trouble breathing. I called the Dr. and he said it could be excercised induced asthma. He is a very active boy who runs non stop and has NEVER had breathing issues before Singulair! It seemed to pass after a few hours. The next fews days he coughed a few times when playing and I thought what the heck is happening to him. Monday at school they didn't go outside so he was fine b/c he didn't run around. Tuesday, they came to get me b/c he was having trouble breathing and one of his teachers whose son has asthma said I think you better give him an inhaler. I called the Dr. ASAP and he approved us to borrow another child's. He freaked out and wouldn't let us give it to him. After 2 epi-shots in the previous weeks, he wanted nothing to do with that. At school the next day, we made him take the inhaler if he wanted to go out to playso he did. He didn't cough but a few times. No excercise at all. Then last night, he got really bad. He started to cough and couldn't stop to the point of gaging and it seemed as though he had developed a ton of phlem and kept trying to swallow. We ended up in the ER where we were told that he has asthma! I am so furious! I don't get this at all! If this report is accurate and my son got asthma by going on it - this will be devastating. We kept him home today from school and took him into the Dr. b/c he continued to cough all night. He is now on Flovent, Albuterol and has an enebulizer. I'm probably the only one of all of us who child did not have asthma to begin with.

Has anyone who did not have asthma before singulair now have any issues? Please let me know!

When I saw that researchers acknowledged the number of potential gene variants that are involved in determining the efficacy of montelukast and then I am reading the reports of the side effects, I am wondering why montelukast was ever approved for seasonal allergies. Asthma is potentially life threatening. But why take Singulair -montelukast for annoying allergies that won't kill you.

----------------------------------------------------------------------------------------------------------------

" However, logically one might predict that it will be the combination of the polymorphisms in these different key regulatory enzymes and receptors that may ultimately determine treatment response. There have been some attempts to tease out the possible contribution of different genes important in this pathway for treatment response to a Cys leukotriene receptor 1 antagonist.18 However, because of the number of potential gene variants that may contribute to efficacy, large studies will be needed to fully evaluate the potential contribution of pharmacogenetic variability in this pathway to treatment response to Cys leukotriene receptor 1 antagonists. Work in the cardiovascular field has demonstrated the potential importance of genetic variants in this pathway to disease risk and also to treatment response,19 suggesting the potential for important effects to be defined in asthma."

(Chest. 2006;130:1873-1878.)
© 2006 American College of Chest Physicians

Pharmacogenetics of Asthma
Ian P. Hall, DM
* From the Division of Therapeutics and Molecular Medicine, University Hospital of Nottingham, Nottingham, UK.
Correspondence to: Ian P. Hall, DM, Division of Therapeutics and Molecular Medicine, University Hospital of Nottingham, Nottingham NG7 2UH, UK; e-mail: Ian.Hall@nottingham.ac.uk

http://www.chestjournal.org/cgi/content/full/130/6/1873

.

Some of you who are following this site may remember that I posted that when I was following the pathways of the leukeotriene receptor antagonist Singulair that I got to a point where I concluded that there has to be a genetic component (meaning that there are different gene groups of people) and that the efficacy of Singulair (and possibly safety) can vary depending upon what gene group people are in. So I took a little time to see if anybody else was already studying that issue. And YES, they are -- including Merck.

quote:

" However, logically one might predict that it will be the combination of the polymorphisms in these different key regulatory enzymes and receptors that may ultimately determine treatment response. There have been some attempts to tease out the possible contribution of different genes important in this pathway for treatment response to a Cys leukotriene receptor 1 antagonist.18 However, because of the number of potential gene variants that may contribute to efficacy, large studies will be needed to fully evaluate the potential contribution of pharmacogenetic variability in this pathway to treatment response to Cys leukotriene receptor 1 antagonists. Work in the cardiovascular field has demonstrated the potential importance of genetic variants in this pathway to disease risk and also to treatment response,19 suggesting the potential for important effects to be defined in asthma."

(Chest. 2006;130:1873-1878.)
© 2006 American College of Chest Physicians

Pharmacogenetics of Asthma
Ian P. Hall, DM
* From the Division of Therapeutics and Molecular Medicine, University Hospital of Nottingham, Nottingham, UK.
Correspondence to: Ian P. Hall, DM, Division of Therapeutics and Molecular Medicine, University Hospital of Nottingham, Nottingham NG7 2UH, UK; e-mail: Ian.Hall@nottingham.ac.uk

http://www.chestjournal.org/cgi/content/full/130/6/1873

And Merck sponsored a study on this which is now completed.

http://clinicaltrials.gov/ct2/show/NCT00116324?intr=%22Montelukast%22&rank=79

Of course, it was sponsored by Merck and paid for by Merck.

I don't know if the study discovered anything but I believe this is an indication that Merck acknowledges genetic differences in populations that may predict the success of montelukast.

I am not any where close to being an expert in this field. I have another background but I believe that there are experts who can tell you exactly why you had side effects from Singulair.

Both my children, ages 4 and 7, are currently taking Singulair chewable tablets for their seasonal allergies. They have been doing so for about three months. At first, I was not consistent in giving them the medicine. It wasn't until recently that I decided I should give it to them as prescribed, once daily before bedtime. During this time I heard about an incident linking this medication to a suicide. I shrugged it off thinking this could not happen to my children. Little did I know that this medication has other serious side effects linked to it. For the past few weeks, my own 7 year old daughter has experienced many of those side effects including stomache aches, headaches, trouble falling asleep, irritability, mood swings, crying spells, and traumatic nightmares. She used to be a fun loving child who loved waking up to go to school. Now she does not want to get up in the morning and hates going to school. She cries easily over the smallest thing and complains frequently of headaches and stomach aches. My son on the other hand has become overly aggressive and I had concluded that maybe his video games or cartoons were to blame. Well, today I found your website and I will take them both off the medication indefinitely! Their allergies were not as severe to begin with so I figure that they should do okay without it. I will probably look into more natural/ herbal remedies to soothe them when they do get their allergies. I will definitley be reporting back as to their results.

Sorry guys. The post below is mine and I left out a critical part of the entry. My three year old daughter was put on Allegra (along with the Singulair and Nasonex) in mid-March which is when her sleeping patterns changed. I've researched the side-effects of Allegra and I can't find sleeplessness anywhere. Therefore, maybe it's the combination of the Singulair and Allegra causing the problem. Does anyone else have a small child on this combination of meds. that is experiencing similar problems?

Thank you so much for all the information! My son was prescribed Singulair pills this fall. He has been taking them for seasonal allergies and we had no problems. These were the sample chewable kind. Then came the pills... Unfortunately I did not see the news or read the article about the side affects of Singulair. Within 4 days my happy well adjusted 10 year old had serious sleeping problems along with stomach aches. He will wake up screaming and crying and cannot tell me what is wrong. He said he had a nightmare but doesn't remember what it was about.

My husband was away on a business trip when I started him on the medicine. He came back to a very unhappy and sleepy child. I asked my son what he was scared of and he asked me to tell daddy that he does not feel safe while he is out of town. He can't sleep unless he is by one of us. He's not safe. His bedroom is 15' from our bedroom! He loves his doctor and begged that I call Dr. Becky so he can talk to her.

I could not take this anymore and started thinking about what was wrong. I went through all his activities, friends he's played with, school problems, anything! Then it hit me, effects of Singulair!

Wow, what an eye opener. Fortunately my husband did not have him take it this morning. He will not be going back to this medication. Ever!

Thank you for the information once again. I hope everyone's child gets better. Everyone wants a happy well child. No child should have to go through this. They have enough pressure as it is without the meds making things worse.

Maeri

I am speechless at all the postings re: Singulair. Both of my sons-ages 12 and 10 - have been on Singulair for over 5years for Allergies/Asthma induced by allergies and after reading the possible side effects, I now realize that my oldest son has been affected. His behavior, sleeping habits and social interaction has changed and in the last couple years has increased out of control. I recently made an appt. for him w/a therapist re: anger issues and as of today, called his allergist re: taking him off Singulair cold turkey. He still takes Zyrtec every day and I'm hoping that will be enough for his seasonal allergies to get him through. I miss my sweet boy and will try to make up to him what I've done by allowing this drug to damage his inner self.
Justin/Jake's mom-Ohio
angelray9698@att.net.

I am one of many that has decided to stop giving my child Singulair. And like many others, I have noticed a great improvement in her behavior.

My question is for those who have done the same. What medication have you replaced the Singulair with and have you noticed any of the same side effects that Singulair was causing? What are your thoughts on Flovent inhaler?

Any feedback would be greatly appreciated. Thanks!

So after reading enough of these replies I've come to a few conclusions:

1) Apparently Singulair should not be prescribed to children.

2) We have some extremely over-reactive parents.

3) It sounds like many of you describing side-effects from your young children also mention that they are on other medication(s). Don't be so quick to blame Singulair for everything. Many medications share the same possible side effects. Unless Singulair is the only medication your child takes, hold your tongue until more definitive studies and investigations are done.

About me -- I'm a 30 year old man who developed asthma when I was 11, and has fairly nasty seasonal allergies (I live in Austin, TX). I started taking Singulair several years ago as I had literally tried every other prescription allergy medicine on the market available for my seasonal allergies. OH MY GOD! I CAN BREATHE AGAIN!

Not only could I breathe through my nose, but the Singulair helped me fight off seasonal allergens (namely mountain cedar tree pollen and Texas oak tree pollen) so much that I was no longer waking up having asthma attacks from my sinuses draining. No longer was I missing days and days of work from "cedar fever" and "oak fever." At long last I finally found an allergy/asthma medicine that works for me.

Now, I also take use Advair (250/50) every day as well. Without a doubt, my life is 100 fold better now than it was before I used the combination of Singulair and Advair on a daily basis. If I miss a day or two of my Singulair, which I have done before, my allergies are noticeably worse and magically get better when I get back on Singulair.

I can honestly say that I have never experienced any depression or suicidal thoughts/tendencies since I have been on Singulair. Undoubtedly there are many others like myself who thank God every day for this medicine. I honestly feel very bad for those of you who have issues with Singulair because it has been a life-saver for me.

This fall, our 3-year old son went on singulair to combat seasonal allergies and "reactive airway disorder." Shortly after he started the medication, he started having terrible mood swings and when he would get angry, it would go into a rage. This was not typical for our son. We thought that he was entering the awful 3-year old stage and that he was starting to show behavior problems. We have been working very hard with him to help him control his anger and moods, but we will be taking him off singulair tonight to see if that makes a difference!

I am 33 years old and have been taking Singulair for 4 years. I have severe seasonal allergies and Singulair was the only RX that would work without knocking me out. I was prescribed to take one a day/everyday. These past two years I have suffered from depression and have had anxiety attacks that make me think I am loosing my mind. Never did my doctor ever tell me it could be caused by my allergy medicine. My marriage has suffered and my kids have to. I had stopped taking it these couple months in the winter and I have been fine. After I saw the news this morning, I was shocked. I had just begun taking Singulair again this month. Just this week, I was already having trouble sleeping.

My prayers go out to the parents and family of the young boy.

My son started taking Singulair last year for seasonal allergies which cause his asthma to act up. He is now 7, and it wasn't until my husband read yesterdays news about the drug that I started to make sense of everything. My son is normally a very gentle, calm child who loves everyone. In the last several months he has developed a temper, is talking back and frustrated easily. His other symptoms include: headaches, stomacher pains,(especially after drinking milk and he has never been lactose intolerant), nightmares, a constant shivering feeling(we live in south Florida), neck pain, mood swings, anxiety and several ear infections within weeks. I am waiting for a call back from our pediatrician. As of today, my son will no longer take this seemingly unsafe drug. I'm also going to do more research on what we can do as parents and patients to help protect the safety of our health.

I have two children on singular as of September 07. When my 6 year old was an infant he was always congested, we changed his formula a couple of times until the doctor decided to do a blood test to check for allergies and the results came back as an allergy to milk. He then started to have sinus infections and had to have his tonsils and adenoids removed. The surgeon said the coughing and the snoring would stop after surgery but it didn't. I was having problems with seasonal allergies myself and was put on Allegra and Veramist so I decided to take him to the allergist as well. He was tested and was also found to have seasonal allergies. Within a day or two after taking the Singulair 4mg chewable tablets he started sleeping through the night with no coughing or sneezing in the middle of the night. My friend just recently had a similar problem with her daughter who is around ten years old. She was found to have asthma but the inhalers that she was put on didn't completely work, so the doctor put her on singulair and her mother said the Singulair is the best. My 14 year old son also has food and seasonal allergies and takes Singulair but not on a daily basis only as needed and he doesn't have any problems.

Behavioral changes started when my son was 3 years old and on Singulair, 4mg chewables. He became more angry, irritable, and even stated a few times that he wished he were dead. He has had trouble concentrating and has frequent nightmares.

my daughter has been on Singulair for 4 days now. She is 2 years old and has bad food allergies that cause very bad eczema. She also has been diagnosed with the start of asthma. After going to an allergist, we were told that she should try Singulair and Allegra for a couple of months to treat her seasonal allergies which have been causing coughing at night and skin break-outs, etc. A day or so after she took the medicine ( Singulair chewable tablets- I haven't started the Allegra yet, it seemed like too much for her to be on ) she has been having very loose stools, and quite a few throughout the day. Also she has hive- like bumps on her back. I stopped giving it to her the day before yesterday because the medicine was the only new thing she had been introduced too. The stools seemed to slow down and the hives seemed to be going away, but she was coughing bad last night, so I gave it to her again thinking maybe all she had was a stomach bug. But this morning we made countless potty stops and her back is bumpy again. Does anyone else have this problem?

Okay- A friend just emailed this site to me, my son is 4 and has been taking Singulair for about 2 years. He has seasonal allergies which seem to be year round, asthma and food allergies. He is on Singulair and Allegra daily, this in it self freaks me out. What I have noticed for at least the past year is that when he is running around or moving a lot he hold his right side and says he has a pain in it, we now call it a "stitch". it happens not from strenuous activity, our doctor just says its growing pains, that doesn't make sense. something is bothering him it happens with somewhat frequency. I am really thinking about his behavior, it seems to me he can change on a dime. from happy to very angry, outbursts and then right back to sweet, yes this could describe any 4 year old, but not any 4 year old is on Singulair. I remember saying to him where is my sweet boy? I feel like that might have been when we started the meds, i am so used to his behavior now that it seems almost normal but there was a time he acted differently. and i do remember saying that.... was it when he went on Singulair???

I don't typically write on message boards, but wanted to share my story. I wish I knew about the affects of singular before I gave it to our son.

My 3 year old son was put on Singular and 2 puffers at age 2 1/2. He had chronic coughing and croup and seemed to always have throat infections. Our Family Doctor thought it was seasonal allergies, (and because he was under the age of 6 - no allergy testing can truly be done) so she prescribed Singular. As tired parents of a little boy who didn't seem to sleep through the night any longer, we did as the doctor advised and gave him the medication every night.

Almost immediately, his behavior changed from a happy 2 1/2 year old to a child with severe tantrums (we never experienced this behavior before), terrible night terrors to the point we were having trouble with him going to bed at night and him telling us every day he had leg pain. He would cry and hold his little leg - limping. Our son could speak at a very young age, so he was able to articulate his feelings/reactions to us. We thought we were entering the terrible "2's" late, but through our experience and ours alone I am certain it was the singular. After this I decided to check online only to be overwhelmed with similar reactions to this drug. We immediately stopped giving the drug to him. We had noticed that his tonsils were getting larger and larger and they would often have infected white soars over them. Off we would go to the Doctor who told us it may or may not be strep and prescribe antibiotics, he would complete a cycle of antibiotics and within 10 days the symptoms would return. We demanded we see a throat specialist to see if the coughing/sleep apnea and terrible drooling could be caused by his huge tonsils. He progressively stopped eating his favorite foods and would wince every time we served him meat.

We finally saw a specialist and at first look at our little boys’ throat, the specialist said 2 things: 1) "Let me guess, he will only eat pasta?" - which was the case, apparently it was the only thing he was able to eat without pain; and 2) "I do not know how this little boy isn't acting out more, he has to be in so much pain". The specialist explained that every time he coughed or ate, the infected soars on his tonsils would burst causing nausea and pain. Because it hurt to swallow, saliva would pool in his throat causing his terrible coughing fits. He had his tonsils/adenoids removed 3 weeks after our visit (which isn't done as often as it used to be) and he has been PERFECT ever since. He hasn't had 1 cold, he hasn't coughed one night and he is eating/laughing/playing like the child he was before singular. DO NOT TAKE SINGULAR unless they can conduct the proper asthma/allergy testing appropriate for the child's age. They were medicating my child with the assumption that he MAY have it. The reason for his coughing and wheezing was his enormous tonsils. A procedure which was hard to go through with a 3 year old, but he is truly a different child today.

I trust this information will be helpful to parents in the same situation.

I have been taking Singulair for almost three weeks now. I have had problems with ear infections/inflammation since May of this year. I have a new Doctor and since I also have seasonal allergies he recommended Singulair. I was wondering why no other Doctor including the allergist that I see ever recommended Singulair to me. At first I thought it was a great idea, but I have noticed the headaches are getting worse, and I still wake up with a very dry mouth. I'm not sure it's worth taking anymore. I was thinking that perhaps the problems I had were also a result of the antiobiotics I was taking, but I finished that prescription a week and a half ago. So it can't be the antibiotics causing the trouble. The only other medication I am taking is the Singulair.
Thanks.

My 7 year old daughter has been on singular for 1 month. I have noticed weigth gain, crabby crabby and mean aggressive behavior....she used to be able to memorize her spelling words in school easily and now cant focus....she has seasonal allergies which 1 time brought me to urgent care because she was wheezing...so she ended up on this singular....i dont know what to do....she has anxiety and just cant focus...but i just dont know if it is the medicine???? or not???? i would have to say yes, her behavior is just mean and she is alittle sweet girl......i am sure there are 100,000 of 7 year old kids with successful treatments....where are those people???? i am going to take her off this medication

I am 47-year old, male. I started taking Singulair about 4 months ago to treat my allergy. I had very bad running nose and itchy eyes and was sneezing a lot. None of the antihistamines were effective. Amazingly Singulair has been very helpful. I stopped taking it few days ago thinking my allergy has gone as the season has gone. But everything is back. After reading these much about the side effects of Cingulair, I am scared that it might be dangerous to continue taking it. I have not experienced any bad effects, but don’t know to tolerate the allergy symptoms or keep taking Cingulair. Is there anyone who has had no bad experience with it after taking it for a long time? Please advise. Thanks.

My 4 year old dd has been taking Singulair for about a year. I stopped giving it to her during the winter months as she has seasonal allergies. But now that she is back on it I have noticed that she has frequent daytime urination, nightmares and muscle pains. We have had her checked for UTI's and diabetes and everything is fine. The dr. just says that her bowel is still growing. But when we stopped giving it to her in the winter she was fine. Now all of a sudden she is back to frequent daytime urination. I am going to discontinue and see what happens. I am really glad to find this sight!

My doctor presribed Singulair for me because of seasonal allergies. I'm 13 yrs old, and I've been on Singulair for about two weeks. After about a week of taking Singulair, I started noticing a few minor side effects. However, they've been continuing to get worse every day I take this drug! Some of the things I've been experiencing on Singulair include fatigue, twitching, stuttering, and lack of memory. Anyone else?

My 6 year old son has had all of these more or less. He has been on Singulair for about 5 months. We took him off last Friday when he started having seizures. It is only now that we are connecting the things he has complained about. He is still going through testing but everytime a test is done it is negative. He is in perfect health. The dr.s are stumped. What happens is, he smells a wierd smell. Then he sees lights. After this he has a bad headache and becomes weak so he lays down. Shortly thereafter he stiffens and starts shaking his arms and legs while clinching his hands. He also grunts and makes a buzzing sound and appears as though he only breathes out. the dr.s say it is not seizures but movement disorder and if it is Singulair it should be out of his system within 3 days... He is still having the seizure type fits and its been a week since we took him off singulair. He is still losing his temper and having horrible dreams as well. Cat scan was normal, EEG was normal, blood work is ok, they want to do an MRI but does this sound familiar to anyone?

I was on Singulair for a few years. I started seasonally and eventually stayed on it all year. It kept my mild asthma and seasonal allergies completely in control to the point where I no longer felt like I had those problems. Even after cold viruses, my peak flows never dropped as far and it didn't take as many weeks to recover peak flow. As a singer, that was very important to me.
Then I spent a year barely able to walk from the severe leg cramps and pain and swelling. My GP was stumped and I had several diagnostic and blood tests that ruled out all the possibilities she could think of. Then I called up Glaxo and asked if it could be the Singulair? Yes, in rare cases it causes edema and/or muscle cramps. My doc took me off and the problems faded away and I'm back to walking. But now my asthma is not doing as well back on the older drugs. Sigh.

In August of this year, we started giving my son 4 mg of Singulair daily for his asthma and seasonal allergies. We just found out about the connection between hyperactivity and Singulair the other day and now everything makes sense. This fall, we noticed his activity level jumped up several notches, he couldn't seem to sit still anymore and would be bouncing off the walls from morning to night. He was pretty high energy before but this was VERY VERY high energy. He could barely sit still to eat meals. He became quite dramatic and tantrums became common - he wasn't the easy-going kid he used to be. And he started waking up in the middle of the night, sometimes sobbing, where previously he had always been a very sound sleeper.

Three days ago we learned about these possible hyper side effects of Singulair and two nights ago we stopped giving it to him. Last night he sat down and actually ate a good dinner with us. This morning, he seemed a tad bit calmer. We are hoping the rest of the effects will go away soon. Needless to say - no more Singulair for him. We'll find other ways to deal with his allergies and asthma.

I've been taking Singulair for almost 7 months, during which I have been only singing its praises. My asthma symptoms completely vanished and my seasonal allergies have been very much under control. However, I'm beginning to notice a pretty constant state of lightheadedness and just in the past few days there have been times when I thought I would faint. In retrospect, I've had a great deal of trouble sleeping through the night. I've also started to get some skin itchiness that I never had before. I'm going off Singulair right away and see how that makes me feel.

My 4 year old son has been taking Singulair for 2 1/2 years. It really helped with his seasonal allergies, asthma and a chronic cough he had. HOWEVER, he too became more aggresive, unfortunately, my sweet angel's personality change was not enough of a red flag for me. Over the past couple of months he's been opening and closing his mouth (tic like), eye blinking, teeth grinding, making sounds with his throat and nose. The more my husband and I talked about it we realized he had been doing some of these things longer, but they were subtle. Now they all came out at once. I have been crying my eyes out, feeling like a horrible mother - thinking my child is possibly developing tourette syndrome. We are do to see a neurologist in 3 weeks, but I just know that it was the Singulair.

I was taking singulair last fall for seasonal allergies but then came down with a terrible cold and stopped for the winter while trying to recover from several different illnesses. I started taking Singulair again in early April for seasonal allergies and have experienced daily nosebleeds after taking it about a week. Anybody else have nosebleeds? Did it stop when you stopped the meds? I'm thinking of trying Zyrtec(sp?) instead. Any thoughts?

My 6 yr. old son was started on Singulair for what
was believed to be exercise-induced asthma back in October 2005. We were only
given a sample pack of approx. 12 doses to try. He originally complained of
headaches and I noticed that it was one of the side effects as listed in the
pamphlet that came with the sample pack. Approximately two weeks later, he was
given a prescription for it at his well visit by his pediatrician (we did
however have a pending appointment to see an allergist for future testing).

I had started to notice some unusual behavior on my son's part (he was making a
slurping-type sound out of the corner of his mouth and he was starting to have
blinking and eye tics - looking up/rolling his eyes/while opening his mouth). I
then stop giving him the Singulair for approximately 2 weeks since we were
planning to see the allergist. I didn't feel right about giving it to him
without actually getting a formal diagnosis yet, plus he still said he was
getting headaches.

I then started second guessing myself and was thinking that perhaps his unusual
behavior/tics were caused by his allergies, so I started him back on the
Singulair.
We met with the allergist and found that he did have seasonal allergies along
with an allergy to dust mites and cats (we have had a cat now for one year), so
obviously they wanted him to continue on the Singulair once daily.

He has been on Singulair regularly now for approximately 1 1/2 months and I have
noticed what my husband and I call tics - he is blinking alot, he still opens
his eyes widely, in the last few days he has started grinding his teeth, tilting
his head toward his shoulder as if he were stretching his neck and I noticed him
today moving his mouth to one side.
Needless to say, my husband and I are scared to death. I only have a small
sense of comfort after reading some of the posts on this site from other parents
who are mentioning possible ticks from Singulair usage. I have been crying my
eyes out daily lately after watching my son's actions. I am fearful that he is
developing Tourette's Syndrome/Disorder and he has an appointment in approx. 2
weeks to see a Neurologist about this problem. I was due to pick-up his next
month's supply of Singulair as I have only one dose left, but I have decided to
stop him cold turkey! I am not going to give him his last dose of Singulair. I
don't know how long it will stay in his system, but I pray to God that this is
the cause and that it is not something worse.

Have anyone else experienced anything similiar to what I am describing? Have
you noticed anything like tics? I would love to hear from someone who has
posted previously about their possible tics with their children and what they
have been experiencing lately? Did you stop using Singulair and if yes, what
have you found? Have the "tics" gone away?

I've read some of the other posting and I'm a bit concerned. I have twin boys who were started on Singulair about 2 years ago for seasonal allergies. They went on it around sept. and remained on it thru may. They came off of it during the summer months but were put back on it again in Sept. My boys were about 2.5 years when they were put on it and now I'm starting to put the pieces together. They have developed agressive behaviors toward me, their father and each other. They are very moody and irritable and have become anxious about being left at school, which was not a problem during the summer months they were off it. They also become very hyperactive after initially taking the medication at night. I also have a nephew who was put on it about a year and a half ago. He is 8.5 and has developed anxiety about going to school, which he did not have prior to taking this med, headaches, and stomache aches. I'm not sure if all these are truly being brought on by singulair, but its highly likely.

I have been taking Singulair for seasonal allergies since April of this year. My allergies have improved, but the other side effects have been grusome for me. I have been so depressed. I'm a RN & at first thought it was just me. Then I started thinking back of when it started. I have also gained about 20 pounds since starting this medication. Most recently I have been having palpitations, feel very nervous, jittery. I kept telling myself it wasn't this medicine, but after seeing these post, I think it is. Especially this weight gain. I just can hardly believe it!

My son is 3.5yrs and has used Singulair for a week this past spring and I have tried it again. Both occasions after only 1 dose he is complaining of a soar throat and his voice is so hoarse he can barely speak. He was prescribed this medication for seasonal allergies. Just wondering if anyone else seen this as a side effect.