October 23th
2008
6:51 PM
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.
July 28th
2008
6:19 PM
Well i just got back from the docs.......no surprise he highly doubted the singulair would have anything to do with an insulin blood level......same old song and dance.......I as a mother don't understand what a leukotriene receptor blocker antagonist is,but i was hoping those i pay the big bucks to that have completed med school do......i am wondering that one.....so i have to see an endo doctor and spend more monies but i have no choice it is the health of my son
-- By flindy | Reply | Private Message me
June 15th
2008
5:09 PM
How does montelukast affect laminin beta2? I don't know but this came up when I cross referenced N106A.
Synthesis of tenascin and laminin beta2 chain in human bronchial epithelial cells is enhanced by cysteinyl leukotrienes via CysLT1 receptor
Cysteinyl leukotrienes (CysLTs) are key mediators of asthma, but their role in the genesis of airway remodeling is insufficiently understood. Recent evidence suggests that increased expression of tenascin (Tn) and laminin (Ln) beta2 chain is indicative of the remodeling activity in asthma, but represents also an example of deposition of extracellular matrix, which affects the airway wall compliance.
We tested the hypothesis that CysLTs affect production of Tn and Ln beta2 chain by human bronchial epithelial cells and elucidated, which of the CysLT receptors, CysLT1 or CysLT2, mediate this effect.
Methods: Cultured BEAS-2B human bronchial epithelial cells were stimulated with leukotriene D4 (LTD4) and E4 (LTE4) and evaluated by immunocytochemistry, Western blotting, flow cytometry, and RT-PCR.
CysLT receptors were differentially blocked with use of montelukast or BAY u9773.
Results: LTD4 and LTE4 significantly augmented the expression of Tn, whereas LTD4, distinctly from LTE4, was able to increase also the Ln beta2 chain.
Although the expression of CysLT2 prevailed over that of CysLT1, the up-regulation of Tn and Ln beta2 chain by CysLTs was completely blocked by the CysLT1-selective antagonist montelukast with no difference between montelukast and the dual antagonist BAY u9773 for the inhibitory capacity.
Conclusion: These findings suggest that the CysLT-induced up-regulation of Tn and Ln beta2 chain, an important epithelium-linked aspect of airway remodeling, is mediated predominantly by the CysLT1 receptor.
The results provide a novel aspect to support the use of CysLT1 receptor antagonists in the anti-remodeling treatment of asthma.
Author: Siiri Altraja, Martin Kadai, Erki Rekker and Alan Altraja
Credits/Source: Respiratory Research 2008, 9:44
Published on: 2008-05-26
-- By concernedcitizen | Reply | Private Message me
June 15th
2008
3:09 PM
I was reading some research from the 90's where one researcher called montelukast an inverse agonist. So then, I looked for any thing more current on that subject. It would seem that genetic variation is again involved.
1: J Pharmacol Exp Ther. 2004 Apr;309(1):102-8. Epub 2004 Jan 12. Links
Inverse agonist activity of selected ligands of the cysteinyl-leukotriene receptor 1.Dupré DJ, Le Gouill C, Gingras D, Rola-Pleszczynski M, Stanková J.
Immunology Division, Department of Pediatrics, Faculty of Medicine, Université de Sherbrooke, Sherbrooke, Québec, J1H 5N4 Canada.
Cysteinyl leukotrienes (CysLTs) are associated with several inflammatory processes, including asthma. Due to this association, considerable effort has been invested in the development of antagonists to the CysLT receptors (CysLT(1)R). Many of these molecules have been shown to specifically interact with CysLT(1)R, but little is known about their impact on the conformation of the receptor and its activity. We were especially interested in possible inverse agonist activity of the antagonists. Using a constitutively active mutant (N106A) of the human CysLT(1)R and the wild-type (WT) receptor coexpressed with the G(alphaq) subunit of the trimeric G protein, we were able to address this issue with ligands commonly used in therapy. We demonstrated that some of these molecules are inverse agonists, whereas others act as partial agonists. In cells expressing the CysLT(1)R mutant N106A exposed to Montelukast, Zafirlukast, or 3- phenyl]-(2-dimethylcarbamoylethylsulfanyl)methylsulfanyl] propionic acid (MK571), the basal inositol phosphate production was reduced by 53 +/- 6, 44 +/- 3, and 54 +/- 4%, respectively. On the other hand, 6(R)-(4-carboxyphenylthio)-5(S)-hydroxy-7(E),9(E),11(Z),14(Z)-eicosatetraenoic acid (BayU9773) and 1- -phenyl ethanone] (LY171883) acted as partial agonists and alpha-pentyl-3- benzyl alcohol (REV 5901) as a neutral antagonist. However, in cells expressing CysLT(1)R and G(alphaq), all antagonists used had inverse agonist activity. The decrease in basal inositol phosphate production by ligands with inverse agonist activity could be inhibited by a more neutral antagonist, confirming the specificity of the reaction. We demonstrate here that Montelukast, MK571, and Zafirlukast can act as inverse agonists on the human CysLT(1) receptor.
PMID: 14718577
-- By concernedcitizen | Reply | Private Message me
May 26th
2008
12:31 PM
I don't have any conclusions to report because I have recruited friends to help me. I got over my head as far as my understanding of this type of chemistry. I am particularly interested in what happens to the quinoline nitrogen during the metabolic break down of montelukast. Nitric oxide is an important molecule to the human body. BUT, however, in excess it is very toxic. The year of this study 1998, some medical researchers got the Nobel prize for their work on nitric oxide.
http://nobelprize.org/nobel_prizes/medicine/laureates/1998/press.html
So I am now working with friends to try to further understand the Merck report on the metabolism of montelukast. I found a Japanese researchers opinion of the connections of montelukast and the cysLT1 receptor showing the nitrogen as a key factor. I was also able to find some work done on mold spores that might give some clues because DPA - 2,6 pyridine dicarboxylic acid in the spore case might yield something about the receptor and/or quinolinic acid 2,3 pyridinedicarboxylic acid. I haven't concluded anything about Fenton reactions as of yet but that is always something to think about.
If anyone has any chemist friends, we could use some real experts in this field not just someone like me, CC, who can read and collect research.
J Med Chem. 1998 Apr 23;41(9):1439-45. Links
Development of a three-dimensional CysLT1 (LTD4) antagonist model with an incorporated amino acid residue from the receptor.Zwaagstra ME, Schoenmakers SH, Nederkoorn PH, Gelens E, Timmerman H, Zhang MQ.
Division of Medicinal Chemistry, Leiden/Amsterdam Center for Drug Research, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
This paper describes the molecular modeling of leukotriene CysLT1 (or LTD4) receptor antagonists. Several different structural classes of CysLT1 antagonists were superimposed onto the new and highly rigid CysLT1 antagonist 8-carboxy-3'- flavone (1, VUF 5017) to generate a common pharmacophoric arrangement. On the basis of known structure-activity relationships of CysLT1 antagonists, the quinoline nitrogen (or a bioisosteric equivalent thereof) and an acidic function were taken as the matching points. In order to optimize the fitting of acidic moieties of all antagonists, an arginine residue from the receptor was proposed as the interaction site for the acidic moieties. Incorporation of this amino acid residue into the model revealed additional interactions between the guanidine group and the nitrogen atoms of quinoline-containing CysLT1 antagonists. In some cases, the arginine may even interact with pi-clouds of phenyl residues of CysLT1 antagonists. The alignment of Montelukast (MK-476) suggests the presence of an additional pocket in the binding site for CysLT1 antagonists. The derived model should be useful for a better understanding of the molecular recognition of the leukotriene CysLT1 receptor.
PMID: 9554877
-- By concernedcitizen | Reply | Private Message me
April 10th
2008
10:36 AM
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.
-- By concernedcitizen | Reply | (2) replies | Private Message me
April 6th
2008
2:34 PM
Is anyone else interested in how many other medications that children or adults who took Singulair started taking after they were prescribed Singulair? If so, would you mind posting what the medication was and what kind of doctor prescribed them?
See comment by cheflette:
about 18 hours ago on Apr 05, 2008 by cheflette, #6727
Concernedcitizen, I REALLY appreciate the hard work you've done looking for how montelukast affects the brain. I think you're making an important point here. Everything we put in our bodies affects other parts of our bodies and I think these research companies forget that sometimes. You can't fundamentally alter a bodily function and expect the rest of the body to ignore it.
The scariest thing to me is that rather than removing the antagonist (in this case, Singulair), doctors will prescribe yet another drug. So many of these children are on a multitude of medications. What a mess.
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"We have no indication that anything about the mechanism of Singulair is consistent with these events (OH REALLY, YOU MEAN THAT YOU CANNOT FIND ANYTHING AT ALL THAT IS POSSIBLY CONSISTENT???)," said George Philip, director of research and product development, according to AP. "But because suicide is a life-threatening event we thought it was important to provide this information in the product label."
In a statement released by Merck, they state that in their own analysis of trials of more than 11000 patients, there was no associated risk between them taking the drug and an increased risk of suicidal thoughts.
-- By concernedcitizen | Reply | (1) replies | Private Message me
April 5th
2008
11:10 AM
If any one is following what research is being done, here is the description of the new study in children.
http://clinicaltrials.gov/ct2/show/NCT00540839?intr=%22Montelukast%22&rank=19
-- By concernedcitizen | Reply | (3) replies | Private Message me
Singulair (8) Armour Thyroid (1) Risperdal Consta (1) Levaquin (1)
June 11th
2009
11:49 AM
I took Levaquin on multiple occasions for a severe prostate infection. I took a 15 day supply...then off for 1 week...another 15 day supply...off for two weeks...and then a 30 day supply. I took another 30 day supply when the infection resurfaced about a year later. During the time I was on it I experienced extreme "arthritis like" pain in my ankles, wrists, shoulders, and especially my back. The infection was over 3 years ago and I have not taken Levaguin since. However, the joint pain has never went away. I can barely climb stairs as my right knee feels like it is going to pop out of socket. The bone pain in my neck and between my shoulder blades is horrible. I visited a doctor (I never even considered the Levaguin as a possible antagonist) and was told that I had spinal degeneration and needed physical therapy. Protect yourself and your family from this drug.
-- By harp00 | Reply | (3) replies | Private Message me