Quote from: chrishoney on February 07, 2012, 05:43:57 AM
1. My understanding is that synthetic estrogens, or what big pharma calls conjugated estrogens (one brand is Premarin), are an ill defined cocktail of estriol, estrone and various other estrogens (see this search on Premarin: http://www.fda.gov/Drugs/DrugSafety/PostmarketDrugSafetyInformationforPatientsandProviders/DrugSafetyInformationforHeathcareProfessionals/PublicHealthAdvisories/ucm169045.htm). 2. So, yes, Premarin is basically oral estriol and estrone, which to be effective, need to be taken in such high doses (estradiol is something like 80 times more potent than estrone) that they pose a significant health risk.
In terms of dosage vs efficacy, oral delivery requires the highest doses, sublingual is a bit lower, with transdermal (patches) and intramuscular (injections) having the lowest dosage to achieve equivalent effects.
For those having trouble with Climara patches coming off before seven days, you could try covering the Climara patch with large adhesive pads (basically very large bandaids 2 7/8" X 4" or 7.3 cm X 10.1 cm) that completely covers the patch and helps hold it in place for the balance of the week.
Hope this helps.
1. Noooooo, not so.
Synthetic estradiol is 'Ethinyl Estradiol' as is used in BC pills (EE) and about 10x stronger then plant based Estradiol 17beta (E2).
2. Not so either... in fact Premarin is somewhat STRONGER then plain Estardiol17b - BECAUSE - it already contains estriol and estrone in addition to estradiol, which is it's MAIN component.
Because it contain these, it is called conjugated = a mix, a cocktail. It contains a lot more than just those 3 items also.
3. Therefore -conjugated estrogen- is something else, as mentioned above in Premarin, but it is NOT synthetic at all! Not Premarin.
It's the least synthetic of the lot as it is made from horse pee, and yes, it contains the whole cocktail of Estrogens, yet also some only 'horse relevant' combinations which are simply dumped by the liver. Premarin is still known for it's high efficacy.
4. To compare, as you say, 80x stronger estradiol to estrone makes not much sense at all, as you will only get estrone and/or estriol in combination with estradiol i.e. conjugated.
The stuff (estrone & estriol) is far too week on it's own to be used for HRT --- all I know. It is used for some specific issues with natal-females like endometrial problems e.g. infertility and such.
You could then also say Ethinyl Estradiol is 800x stronger then estriol or estrone... now what will that mean?
Using no BC pills for birth control? ...
Note: That's why the stuff (EE) is always measured in micrograms (mcg) and not in milligrams (mg) as is estradiol (E2).
The highest dose with any patch known to me and my doctor will give 0.1mg (100 micrograms) estradiol17b!
Now compare that to 2mg HRT oral estradiol17b pills...
~ 90% of the oral stuff is dumped by the liver during first-pass - before ANYTHING is metabolized into estrone, estriol, glucuronides and sulphates...
Just to clear up some confusion - I hope... :-)
Axélle