Quote:
Originally Posted by Peter B
Or ask your pharmacist for help, as there are several of these things available over the counter.
I take Restavit.
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Restavit is not a muscle relaxer..it is an antihistamine (doxylamine) which is
sedating and therefore used to induce sleep. It is also not innocuous just because it is over the counter:
Quote:
Toxicol Appl Pharmacol. 1996 Dec;141(2):584-94.Click here to read Links
Effects of doxylamine succinate on thyroid hormone balance and enzyme induction in mice.
Bookstaff RC, Murphy VA, Skare JA, Minnema D, Sanzgiri U, Parkinson A.
The Procter & Gamble Company, Cincinnati, Ohio 45040-9462, USA.
The effects of doxylamine (as the succinate salt) on microsomal enzyme activity and serum thyroid hormone levels were examined in B6C3F1 mice following dietary exposure for 7 or 15 days (0, 40, 375, 750, or 1500 ppm in diet, expressed as free base doxylamine). In addition, the hepatic P450 enzyme inducer sodium phenobarbital (375 ppm, expressed as free acid phenobarbital) was used as a positive control for CYP2B induction. Exposure of mice to doxylamine produced dose-related increases in liver weight at both time points. Liver weights were also increased in the phenobarbital-treated mice. Doxylamine treatment caused a dose-dependent increase (up to 2.6-fold) in liver microsomal cytochrome P450 in both male and female mice, at both time points. Analyses of the activities of various hepatic microsomal cytochromes P450 indicated that doxylamine caused a marked induction of CYP2B enzymes. This was demonstrated by a large increase in the O-dealkylation of 7-pentoxyresorufin (up to 38-fold) and the 16beta-hydroxylation of testosterone (up to 6.9-fold), both of which are indicative of CYP2B induction. In addition, like phenobarbital, doxylamine treatment resulted in a modest induction of CYP3A and CYP2A enzymes and approximately a 50% increase in thyroxine-glucuronosyltransferase activity. Doxylamine did not appear to induce P450 enzymes in the CYP1A, CYP2E, or CYP4A enzyme subfamilies. None of the enzyme-inducing effects of doxylamine could be distinguished from those of phenobarbital. These results suggest that doxylamine is a phenobarbital-type inducer of liver microsomal cytochrome P450 in B6C3F1 mice. Exposure to either doxylamine or phenobarbital also resulted in decreases in serum thyroxine (T4) levels (approximately 80% of control) with compensatory increases in serum thyroid-stimulating hormone levels (approximately 4-fold). No clear changes in serum triiodothyronine levels were apparent. These findings are consistent with the hypothesis that doxylamine increases the activity of those hepatic enzymes involved in T4 metabolism.
PMID: 8975784 [PubMed - indexed for MEDLINE]
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Drugs that induce enzymes increase the metabolism of other drugs.
The CYP2B system metabolizes steroid hormones.
Here is a monograph on Cytochrome P450 systems:
http://www.aafp.org/afp/980101ap/cupp.html
Doxylamine also has a checkered past for tumor induction:
here is an explanation for that:
http://findarticles.com/p/articles/m..._15784856/pg_3
Doxylamine has been looked at for a decade in USA because it was implicated in
causing birth defects (Bendectin)...after much examination it was released here
as over the counter sleep aid and use in cough/cold products.
The pregnancy concern is important for women who decide to use doxylamine
regularly. Even though it has a pass by the FDA some women may want to
be careful if they are cautious types wanting to become pregnant. I would not use
doxylamine without OB-GYN approval, myself.
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All truths are easy to understand once they are discovered; the point is to discover them.-- Galileo Galilei
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Weezie looking at petunias 8.25.2017
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