Singulair and allergic reaction

My son has been on Singulair for about a year and a half...it really seemed to help his allergies...at least at first. This winter has been very dry and I have been having to give him other over the counter allergy medication as the Singulair isn't helping much. He also started losing weight..just not hungry. At first that was ok as he needed to lose a little but then he was getting too thin. He wasn't eating much at school but refused to take a lunch from home. I took him to the doctor just recently to see if he was physical ok since I didn't know what was causing the weight loss. The blood testing showed everything was normal and I just told him he had to start eating better...he has somewhat...but also he finally told me he has been feeling very depressed...seriously depressed and having suicidal thoughts too due to some kids picking on him at school.

I knew there were problems as he complained alot but I had no idea it was this serious. I have taken him out of that school. Right now I don't know if the Singulair could be adding to this depression or if its all just due to the bullies. While he complained a lot he never acted as if it was bothering him that badly or I would have gone to the school about it. Anyway I stopped the Singulair and am going to see if his mood improves or not. After reading some of the scary posts on here regarding the side effects I am wondering if this is a good idea stopping it or not. I am waiting for a call back from his doctor on it. Since its once a day..its kind of hard to wean them off of it...but I could cut it in half ..do that for a few days, then cut it smaller and so forth. His is chewable so I could do that with no problems. He is 13.

My 9 year old son started Singulair 5mg about 8 months ago. Shortly after, he started to occasionally complain of stomach pain and not being hungry. About 2 months ago, they changed the dosage to 10mg. He now has chronic diarrhea and severe weight loss. We stopped the medicine about 2 weeks ago, but he's not "back to normal" yet. He's never had any digestive problems before. The doctor's recommending endoscopes, and we're at our wit's end.

My 2.5 year old son has been taking oral Singulair granules for 5 days. He has developed a vasculitic rash on his arms and legs. Is this a known side effect of the medication?

I'm an adult female with severe sinus polyps, adult onset asthma and allergies. Initially Singular seemed to be helping my nasal polyps, when nothing else helped in any way. I made several attempts to use Singular, and proved repeatedly that this medication did, in fact, cause me severe side effects - even when I used a childs dosage. While using an adult rx for Singular, I immediately began experiencing horrific nightmares (which I have never had in my entire life). I also had extreme knife like pains in both ears, which made me feel like I had a severe ear infection, chest pains where it felt like a cinder block was lying on my chest, and migraine like headaches (which I've never had). I stopped the medication after about a week and the nightmares went completely away, but it took me a couple weeks to recover completely because I developed what felt like a respiratory infection and ear infection as soon as I stopped using it. Because Singular seemed to slightly reduce my nasal polyps on my first attempt, my allergist suggested I try using it again - almost a year later. When I first began, I completely forgot about the negative side effect and why I stopped using it in the first place, and just gave it another try. I again experienced the same horrific nightmares, ear pains, but this time got a strange rash/cluster of blisters under both eyelids which my eye doctor confirmed was an allergic reaction to something I was using. Singular was the only medication I had changed. My allergist thought I should give it longer to see if the symptoms went away (because they probably weren't caused by this medication - and were due to something else ???). Fearing going to sleep, I decided to try taking the medication in the morning instead of night, and had my physician reduce my rx to a childs dosage (5mg). The nightmares lessened, and the blisters under my eyelids went down, so I continued using Singular for about a years time. What I didn't realize, was that over this time I was becoming depressed, fatigued, and became easily agitated and short-tempered, which was very different since I was normally a very happy, energetic mom. My nasal breathing seemed to be slightly improved, so I just kept taking the medication - not realizing that it was causing all of the other problems I was experiencing. I became so fatigued and depressed feeling, that all I wanted to do after I got my kids off to school was to sleep until it was time to pick them up in the afternoon. I was also experiencing stomach pains for unknown reasons. I was certainly not myself. I didn't realize that while I was using Singular I had lost complete interest in everything that I normally loved in my life. And please note I'm 45 years old, and I was using a childs dosage. ( I can only imagine what this medication does to a child. )Fortunately for me, I accidentally forgot to refill my prescription for a few days and noticed that my depression started to improve. I decided not to refill my rx and stay off it to see if I continued to improve - and I have. Unfortunately, even though my depression has all but gone away, I'm experiencing symptoms which must be from withdrawal of the medication - and they are just as scary as the side effects were. Now that I'm not taking Singulair any more (and I've made no other medication changes), I have extreme fatigue beyond belief, and ache everywhere. My muscles are in such pain that I'm having difficulty doing things I would normally do. I have extreme weakness in both arms and legs, and my back aches almost constantly. And strangly enough, my asthma and allergies have slightly improved since stopping Singular - I thought for sure my allergies/asthma would worsen when I stopped completely - but they did not. All I can say is - please trust what your body is telling you - even if your physician tells you otherwise, and do not use this medication or any other if you experience adverse side effects to it. I would never give this medication to a child that wasn't old enough to tell me what he/she was experiencing, and would document the childs temperament, ailments if any, and what changed once the medication was started - and discontinue it immediately if even one adverse side effects occurred. One last note - I am still experiencing vision problems, which I feel are due to using this medication. Hopefully, no other permanent damage to my body will result from the Singular that I've already used - and I hope you Singular users will recover completely too from its dangerous side effects. Wishing you the best of health!

I have two sons on Singulair, my three old was suspended today from pre-school for bad behavior. Screaming, biting, scratching, and hitting have been going on for the last few months. But worse the past two weeks. He has always been active and played like a boy, but he has been getting violent. We have tried positive reinforcement, praising good behavior both verbally and with rewards, I have tried time-out, being grounded, not being able to participate in activities, no t.v. and old fashioned butt spanking. All of this with no positive results. I am not looking for an excuse for my child's behavior, but could Singulair really be the cause of his aggression?

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.

I spent the weekend reading about the development of Singulair. The early studies recognized that the first phase of the acute asthma response bronco-constriction was probably not caused by leukotrienes. They identified histamines and prostaglandins as the probable sources. I don't think that changed because the Singulair literature states that it should not be considered as a treatment for that. Leukotrienes were a source of inflammation caused by eosinophils and mast cells present in greater numbers (than normal) in airway tissue. So, it was beneficial to find a way to decrease that.

The cysLT1 receptor was identified as source of the signals that tell the cells to produce leukotriene. The receptor, a gene, consist of 337 (they think) amino acids. They modified a compound that would bind to that receptor thus blocking the cells ability to produce leukotrienes. This compound is very specific. It was formulated to bind to the "model" receptor. This compound will not even bind to cysLT receptor sub-types. (That is the good thing.) There is an enormous amount of research that discusses the genetic variability of the chemical reactions that occur in the leukotriene (calling it this for simplicity) pathway. We are also seeing that a number of researchers would like to use gene profiles to predict whether patients will respond favorably to different asthma/allergy drugs. ALL PATIENTS HAVE A RIGHT TO KNOW IF IT IS INHERENT THAT SOME PEOPLE WILL NOT RESPOND TO SINGULAIR OR RESPOND ADVERSELY.

There are many studies from the 1998 era that conclude that montelukast is not effective for everyone. Those researchers stated that it can be predicted that those people who are going to respond favorably will do that within the first 14 days or so. That conclusion would be consistent with a genetic component for efficacy and safety of Singulair. Those doctors concluded that those who did not respond within that time frame should not take Singulair for fear of harming them. That makes good sense.

The Italian researchers wanted to know if there was more going on than blocking leukotrienes in the action of montelukast. They set up a "test tube" study regarding montelukast, the cysLT1 receptor, and some t-cells that they selected. Why? Researchers always have something on their minds. They observed the death of these particular t-cells.

Montelukast is a quinoline. We basically know of quinilines and quinolones as compounds that were invented as broad spectrum antibiotics. They work because they interference with bacterial DNA so they cannot replicate themselves. Montelukast is a quinoline modified to bind with the cysLT1 receptor (a gene) and prevent that gene from activating. That's consistent with what a quinoline/quinolone does.

So what does montelukast do in blood plasma if it does not bind to the receptor because of genetic mis-match? (If montelukast does bind, then a chemical reaction has occurred and the liver will break down the by-products. Montelukast metabolized in 10-12 hours.) What happens if it doesn't bind? How long before it breaks down? Does it produce toxic by-products?

I want to know what happens to lymphocytes such as t-cells just because montelukast is a quinoline. Maybe nothing but what's up with the Italians researchers? I want to know if montelukast has the capability to interfere with lymphocytes who can clone themselves. That could be a good thing under circumstances when these lymphocytes are causing inflammation. But it could be a bad thing in the case of normal individuals with no problems.

I want to know if the bad side effects are due to the fact that the body has to break down and metabolize a quinoline that did not bind to the receptor for which it was created. The side effects of Singulair are strangely similar to what is observed in the quinolones such as levaquin. I have not as yet been able to compare montelukast as a quinoline to levaquin as a quinolone. I am hoping to find something on these categories. There may be no reason to worry that they cause similar damage. But frankly, I think that there is. There is some terrible chit happening to some people. The scariest is the neurological damage.

All of these questions would be in the everybody pharma knows to ask category. I don't know where the answers are. I haven't found them as of yet. Maybe there are no answers. We have to remember that Singulair and Vioxx were released in the same year. They have continued to be drugs under the current executive management of Merck. If the Vioxx marketing promoters had their ghost writers, why not the Singulair marketing promoters. The genetic component appears to be widely accepted but we haven't heard one thing about even that.

I think that it is sad that maybe the marketing of Singulair as one stop shopping for asthma/allergies may have destroyed the original concept. I really think from reading the original work that they knew that they couldn't engineer a drug for one size fits all. Everybody gets harmed when information is withheld.

Shame on the allergist who yelled at the mother who wanted to discuss issues. Does he know exactly who is allergic to Singulair and who isn't? Get him a dunce hat. Just because Singulair is marketed for allergies does not mean that you cannot be allergic to it. See the power of Madison Avenue? The ad agencies focus group these drugs to death. The ad agencies cleverly craft the product information. A good piece of legislation would be to prohibit consumer drugs ads.

I am a 47 year old male who took 3 days of 10mg singulair ending April the 16th. On the 4th day, I was walking around in a national chain store and started getting severe numbness and tingling in my arms and legs.
According to the info. pamphlet that comes with the drug, this can be a serious adverse reaction.
About 13 days later, I still get episodes of tingling and numbness in different areas of my arms and legs, and now, some areas on my face. My family doctor says there is nothing to be done about it, and my allergist says I may need to see a neurologist. I think the doctors need to go see a neurologist and have their heads examined for giving us this garbage to take in the first place!
Never had any of these problems until a took singulair! Hope these side effects aren't permanent!
Good Luck to you all, and may all of us get healthy again real soon!

I was prescribed Singulair last winter after a severe allergic reaction. I have taken it throughout the winter with no noticeable side effects. For the past several days, however, as the pollen count has risen, I have been experiencing strange symptoms. I feel a bizarre pressure in my head, and a ringing of sorts in my ears. Also, I can't sleep - I feel exhausted, and try to go to sleep, but I wind up feeling agitated and have to get up out of bed.

Hi. My eight year old daughter has been on singular for 6 months. She has had chronic stomach pains that she says feel like pressure. Her appetite is terrible. She always says she isn't hungry. I have to search for anything I think she will eat. She is very tall and very thin for her age. She grew an inch in the last year but gained no weight. First time her growth just stopped. No surprise as she doesn't want to eat. I took her to the doc several times and they think she has acid reflux and have given her 2 different acid eliminators ( which freak me out as well) Said she should see a gastroenterologist. We have appointment in March . I started reading this site and thought well maybe it's the singular. So I called her allergist and told them I was taking her off to see if that's why she has the stomach problems. They said I could since it wasn't a big trigger time(seasonal) and she wasn't sick with any cold or flu) She gets mild asthma when sick. Her allergist asthma doc thinks her stomach aches are related to the mucus dripping into her stomach. I have taken her off all meds to try to see if it could be the Singular. She also has been very tired and can't keep up in her dance classes. Her school teacher had to put her in the front of the class because she said she wasn't paying attention. She seems to lose it over anything that requires focus or attention.She also seems kind of depressed. She is worried that something is really wrong with her. This child used to eat normally and is gifted academically .Her tests results(taken while on the Singulair) went way down from last year. She was put in gifted pull out program from last year results but would have barley made it in this year based on her much lower scores. That does not make sense to me. Never has had attention or focus problems before. I will keep everyone posted. Does anyone know how long it might take to get this drug out of her system? Has anyone else had this kind of reaction to this drug? I also wonder whether she had reflux before but this made it worse? I had her blood tested for Celiac and general stuff and nothing showed up.I wanted to get the Singular out of her system before we see the G.I. doctor. anyway thanks, Elizabeth

Hi,

I had a systemic allergic reaction to an allergy injection. I was treated at the hospital with Benadryl and Prednisone. I was told to continue to take both, but still was having problems with sinus inflammation related to the reaction a day later. I saw my Dr. who told me to up the Prednisone and start taking Singulair.

Well I started having side effects worse than the sinus inflammation I originally had within a few hours of taking the Singulair. I totally chalked them up to Prednisone side effects, since that drug has so many issues. But the side effects were different than those listed from Prednisone, and different from the last time I had to take Prednisone for an allergy attack. I had INTENSE head pressure (not just the sinuses, but everywhere), muscle tightness/pressure in my neck muscles and at the base of my skull. I don't know if this was a side effect or not, but I had freezing hands and feet, also VERY cold.. except my face was hot. I also got hot flushes occasionally in my body, like on the backs of my thighs. I also felt "out of it".. very dizzy and slow to respond. I was also very confused by why my sinus inflammation was not really responding to the Prednisone since it is such a strong anti-inflammatory. Well, I stopped taking the Singulair last night after reading this site, and I am feeling back to normal! Even my sinuses have unplugged. I suppose this could all be something besides the Singulair, but I am not chancing it again.

Singulair has been a good thing for my 4yr old daughter. She has only had a few asthma symtoms since being on singulair. She has been on it for almost 3 years. The only issue I have had is that tonight my older daughter gave her a dose and I gave her a dose not knowing she already had one. Does anyone know if this can be a serious thing?

I have taken Singulair for four days for an allergic reaction to mosquito bites. I have had vivid dreams that whole period and my blood pressure has gone up from 120/70 to 140/80 - in those four days. I will not take it any longer.

I just started taking Singulair. I took it Wednesday evening with no problem. I took it Thursday evening and woke up in the middle of the night with vertigo. This lasted for a few hours. It was horrible. I called my allergist and he said this was not a typical reaction and to take it again tonight. No Way! On the Singulair website they said extreme dizziness is a rare allergic reaction. Has anyone else has dizziness or vertigo with Singulair?

In response to the latest post:

I have been taking Singulair for the past week and have also broken out into hives. I have hives on my back, shoulders, chest, and sporadic bumps on other parts of my body. I thought it was just part of my seasonal allergies (albeit a very severe allergic reaction), but also suspected Singulair. I'm glad I Google searched the side effects and found this. I'm going to discontinue immediately.

Stomach pains, nausea and vomiting, skin itching. My skin started itching the day after I started taking Singulair. Stomach pains started two days later, and progressed to vomiting the following day. I stopped taking Singulair because I couldn't keep it down; when I felt better the following day, I took it again - and started feeling worse within a few hours. I called my doctor and he said it sounded like I was having an allergic reaction to the drug and took me off it immediately.