Genetic variation symptoms and conditions

I was put on Singulair about three weeks ago, and noticed immediately that my mood had changed. I am an adult ,and felt this sense of sadness, anxiety, solitude, not wanting to be around anyone. I took myself off the drug and have tics all over my body and eyelids ,which is driving me crazy! I even had heart palpitations ,which are very distressing. Today it seems to be better, and this is day three off the med. The only way I can explain how I felt on this drug is doom and gloom.

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

Results: DNA was collected from 252 participants: 69% were white, 26% were African American. Twenty-eight SNPs in the ALOX5, LTA4H, LTC4S, MRP1, and cysLT1R genes, and an ALOX5 repeat polymorphism were successfully typed. There were racial disparities in allele frequencies in 17 SNPs and in the repeat polymorphism. Association analyses were performed in 61 whites. Associations were found between genotypes of SNPs in the ALOX5 (rs2115819) and MRP1 (rs119774) genes and changes in FEV1 (p < 0.05), and between two SNPs in LTC4S (rs730012) and in LTA4H (rs2660845) genes for exacerbation rates. Mutant ALOX5 repeat polymorphism was associated with decreased exacerbation rates. There was strong linkage disequilibrium between ALOX5 SNPs. Associations between ALOX5 haplotypes and risk of exacerbations were found.

Conclusions: Genetic variation in leukotriene pathway candidate genes contributes to variability in montelukast response.

http://ajrccm.atsjournals.org/cgi/content/full/173/4/379

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.

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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?