American college of chest physicians symptoms and conditions

Why does Singulair cause these symptoms? I am going to give my explanation which is only a HYPOTHESIS. This should not be categorized as any thing but an educated guess. This is not backed by scientific research because nobody will do any research that would appear to anger
Merck even if people are suffering in the thousands.

1. The original research that preceded the development of Singulair (montelukast) seemed to focus on the theory that asthma was caused by an unusual immune response to certain pathological stimulus. There are many references to the observation that a high percentage of asthma sufferers are people whose asthma is caused by fungus. Many people suffer from asthma and are told that they are allergic to dust mites. Dust mites can live only because the fungus aspergillus pre-digests the
food source that dust mites can then absorb. Other sources of fungus occur in the home due to dampness or problems with wood rot.

2. The body's immune system fights certain categories of pathogens such as bacteria and fungus by creating nitric oxide which kills them at the site where they try to enter the body. The mast cell is the immune cell that is responsible for the production of nitric oxide. Mast cells are found in the skin, airways, intestines etc. The mast cell is capable of many different types of biochemical functions that are designed to signal other cells or other chemical responses. When the mast cell knows that pathogens
are present and nitric oxide is NOT produced, then it signals other immune cells to be sent to the site of the infection. Thus in the case of asthma, it is known that excessive numbers of eosinophils appear in the airways and these cells create inflammation.

3. Singulair was developed for asthma and later allowed to be prescribed for other reasons. I believe that montelukast probably creates a source of nitric oxide that prevents the mast cell from signalling for other immune cells to arrive at the source of infection. I arrived at that conclusion from studying the chemical structure of montelukast, the chemical structure of the gene cysLT1 receptor, and the chemical structure of the cell wall of fungus which would be what the mast cell uses to determine "what to do in order to kill the fungus."

The researchers who invented montelukast first had to clone the gene-cysLT1 receptor meaning that they had to be able to identify the gene and replicate it. Then by trial and error they had a find a "chemical"
that would bind (connect chemically) to the cysLT1 receptor. The theory would be that montelukast would take the place of the fungus or other pathogen and thus prevent the gene from reacting to produce the
responses that the sick patient with asthma produced. Merck says in the literature that montelukast binds with the cysLT1 receptor in order to prevent the mast cell from signalling the eosinophils to arrive in excessive
numbers that cause inflammation. I believe that montelukast is also causing the production of an amount of nitric oxide that is actually killing the pathogens that are present. For one thing, I would think that it
would be dangerous to incapacitate the immune system in that way without providing a way to kill the pathogens. I don't believe that the asthma response is just allergies to something like dust. Pollen from trees and flowers is loaded with fungus spores.

4. IF, IF, IF, montelukast does actually produce nitric oxide, then it does so by binding with the gene. Any place in the body where a molecule of montelukast encounters the cysLT1 receptor (a gene) then the corresponding molecules of nitric oxide are produced before the liver enzymes break the montelukast molecules up. Nitric oxide is TOXIC and
INFLAMMATORY. So let's look at the symptoms in regard to the location of the cysLT1 receptors. The location of these symptoms would not be places in the body where the mast cells normally encounter fungus or bacteria. The cysLT1 also has other functions in that it communicates with the cysLT2 receptors. Obviously, nitric oxide
should not be produced in these locations because of the signalling effect of nitric oxide on other physiological functions.

a. intestinal pain - the cysLT1 receptors are located in the small intestines
b. leg pain actually caused by vasculitis - cysLT1 receptors are found inside blood vessels- consistent with the fact that montelukast causes
Churg-Strauss
c. some people who didn't have asthma develop asthma - the cysLT1 receptors are in the airways
d. nightmares, depression, neurological damage - when montelukast penetrates the blood brain barrier probably due to unusual conditions of blood pH or electrolyte imbalance then nitric oxide in the brain causes neuron damage and excitoxicity

5. Why do some patients not experience side effects? Probably because genetically they are completely compatible with the model that researchers created when they cloned the cysLT1 receptor gene. I didn't not find any information about whether researchers knew that there are many different variations of this gene.

6. IF, my theory is even close to being correct, then why doesn't Merck do anything about researching these side effects. Maybe because nobody in the company knows how this drug works but the researchers who created it. All of the Merck literature is very vague about any biochemical information.

Again, this is just speculation and hypothesis. I have made an attempt to put this in simplistic language and therefore sacrifice scientific accuracy. But, I think that you will get the point.

SINGULAIR IS VERY DANGEROUS TO PATIENTS WHO EXPERIENCE NEGATIVE SIDE EFFECTS. DOCTORS SHOULD JUST REALIZE THAT
THOSE PATIENTS ARE NOT COMPATIBLE WITH THE MODEL FOR THE DRUG.

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.

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" 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.