arimedex or nolvadex

[tammyp]

which is better?

why choose one over the other?

experiences?

[sassy69]

They are two different "estrogen blockers" first of all, so its not something like a comparison between brands or quality where one is "better" than the other. Nolvadex is a selective estrogen receptor modulator (SERM) which basically means it is able to match up w/ estrogen receptors that ovary-originating estrogen use to propagate the "estrogen process" -- so if you're basically faking out these receptors, you interrupt the estrogen cycle. So this would apply to estrogen & its impacts (e.g. estrogen-pattern fat depositing around the butt / hips / thighs) of a pre-menopausal woman but probably have little affect on a post-menopausal woman or woman w/ a hysterectomy (not sure about partial or full hysterectomy though...)

Arimidex is a aromatase inhibitor (AI) which acts specifically on estrogen converted from testosterone. Two sources of this would be use of AAS / exogenous test, and androgens produced by the adrenals. The adrenal source would be present in a pre- or post-menopausal women, but would be the minor source of estrogen relative to that produced by the ovaries. In the absense of that, this is the remaining source of estrogen for post-menopausal women. Use of aromatizing AAS would be the other source. This is the same scenario that men who cycle, use AIs to limit the impacts of estrogen, in the form of water retention, gyno, etc.

So which is better? I guess to start, which is more appropriate to the situation? Are you cycling or not? If yes, are you cycling something that converts? E.g. a testosterone? Deca? Winstrol, anavar, primo, EQ are commonly used AAS that do not convert. Is your own natural estrogen still the primary source of estrogen? (I.e. are you pre / post-menopausal)?

Based on the above logic, let's consider a beginner cycler,say a 30 yr old figure competitor running anavar for a show. In this case, Nolvadex would probably be the appropriate choice as the thing arimidex is going to affect would be the adrenal converting estrogen. Nothing from the anavar, and not impacting the primary source of estrogen, the ovaries.

Now consider a more advanced, 35 yr old FBB running some test propionate in a stack w/ EQ. EQ doesn't aromatize but prop does. Adex would help address the test conversion, as well as the adrenal converted estrogen. It wouldn't be unheard of to also include nolvadex to address ovarian estrogen because this person is still pre-menopausal.

I'm sure SS can add a lot more insight, but just looking at the compounds and what they do, this is the basic stuff.

[sassy69]

For ref, from isteroids.com:

Nolvadex

Chemical Name: Tamoxifen Citrate
Drug Class: Selective Estrogen Receptor Modulator

The below article about Nolvadex will inform you about the drugs chemical make up as well as its history. Isteroids.com gives you articles just like this one on all of the steroids that we keep up to date on, including clomid, arimidex, winstrol and many, many others.

Really, if the truth were known, this was the very first compound used as an “ancillary” medication by steroid-using athletes. Dan Duchaine had first speculated that it could possibly be used by bodybuilders to halt the development of gynocomastia (breast tissue in males), because it was used to stop breast tumors in women. He was, as usual, correct. Since then, Nolvadex has become the most widely used medication in the world for men on a steroids looking to avoid gyno.

Nolvadex is a SERM or Selective Estrogen Receptor Modulator. The “selective” part means that it acts as an estrogen agonist in some tissues and as an estrogen antagonist in others. The “Estrogen Receptor Modulator” part means that it acts on the Estrogen Receptor (called the "ER" but having nothing to do with George Clooney or Anthony Edwards).

The estrogen receptor's ligand binding domain is just of a number of amino acid sequences "folded" into a series of helixes, which have the ability to change conformation. Different stimuli (such as Nolvadex) are well documented to have the ability to change the conformation of a very important helix (helix 12, for those keeping score at home).

When estradiol binds the ER, this particular helix takes on a conformation that allows DNA transcription to mRNA, and estrogenic effects are then expressed in the body. When Nolvadex (Tamoxifen) binds to it, the antagonist changes the shape of this helix in such a way that it now folds (or bends) in such a way to prevent proper binding of estrogen, and subsequent transcription of DNA to mRNA.

The ER (remember, no George Clooney, no Anthony Edwards) contains two areas called AF-1 and AF-2. Nolvadex actually only inactivates AF-2. Since there are two areas that can can initiate transcription of mRNA, and Nolvadex is estrogenic in some tissues but an anti-estrogen (sort of) in others,it is possible that AF-1 is the dominant domain of estrogen gene transcription in the liver (for example) but not in mammary (breast) tissue. Thus, Nolvadex exerts different effects as regards estrogen, in different tissues.

Hence, we can see that the effect of Nolvadex is via the mechanism of estrogen receptor blockade of breast tissue (1). Contrary to popular opinion, total body estradiol actually increases with use of Nolvadex. It is not, as it’s often called an “Anti-Estrogen.”

Some other positive effects of Nolvadex (acting this time as an estrogen agonist) is that it can be beneficial to a properly functioning immune system as well as your lipid profile (cholesterol) should also show marked improvement with administration of tamoxifen(2). It’s actually very useful stuff during a cycle for immune, joint, and lipid benefits.

Nolvadex also has some highly important and practical roles for a steroid using athlete who is coming off a cycle. Hypogonadic and infertile men given Nolvadex, saw significant increases in the serum levels of LH, FSH, as well as testosterone levels(3)(4). In fact, 20mgs of Nolvadex can possibly raise your testosterone levels approximately 150% (5). SO clearly this is something we should consider using not only during a cycle to prevent gyno, but especially afterwards, to restore our natural hormonal function.

Unfortunately, it has been linked to reduced gains in some bodybuilders. This is as a possible result of Nolvadex’s potential to possibly reduce IGF (Insulin-like-Growth-Factor) levels, which are important for muscle growth. Additionally, some people report vision problems with its use, but I didn’t find that to be the case for me.

Still, for PCT, or even on a cycle, most people find Nolvadex to be an indispensable product.


References:

1. Klin Padiatr. 1987 Nov-Dec;199(6):389-91.

2. Bruning PF, Bronfer JMG, Hart AAM, Jong-Bakker M, tamoxifen serum lipoproteins and cardiovascular risk, Br. J. Cancer 1988 Oct, 58 (4) 497-9

3. Stimulation of calcitonin secretory capacity by increased serum levels of testosterone in men treated with tamoxifen. Int J Androl. 1987 Dec;10(6):747-51.

4. Hormonal changes in tamoxifen treated men with idiopathic oligozoospermia Exp Clin Endocrinol. 1988 Dec;92(2):211-6.

5. Fertil Steril. 1978 Mar;29(3):320-7.

Arimidex - Liquidex

Chemical Name: Anastrozole
Drug Class: Type-II Aromatase Inhibitor

Isteroids.com has a discussion forum about all anabolic steroids. We also have many articles about different steroids and other trends in steroids, such as the one below about Armidex-Liquidex. As an open forum, we discuss all manner of topics surrounding the issues important to bodybuilders, including legal steroids, steroid use and other current topics, such as Human Growth Hormone.

Arimidex is a type-II aromatase inhibitor (usually just called an AI). In the case of Arimidex, or any Type-I inhibitor, it works by binding to the substrate (the aromatase enzyme) thus rendering it inactive and therefore unable to convert testosterone into estrogen. In clinical use, drugs in this class are used to halt the progression of Breast Cancer in women, as well as for a preventative measure in women who are in a high risk group . In our little world of illicit steroid use, athletics and bodybuilding, it is used as an ancillary compound on a cycle containing steroids which aromatize (undergo a specific metabolic shift) into estrogen.

The primary reason we would use something like this is because excess estrogen in males can have many undesirable effects such as causing a more “watery looking” weight gain, or even gynocomastia – the development of breast tissue in males.

Arimidex halts the conversion of testosterone into estrogen, and thus helps to prevent those side effects from occurring. Typically, in breast cancer studies, we see a dose of about 1mg/day being used, and in steroid using athletes, this is also the amount we would often see. That dose may be slightly excessive, however. In a study conducted on males, examining estrogen suppression in males caused by Arimidex, both .5mg and 1mg doses of were shown to decrease estrogen by around 50%. In both the 1 and .5mg groups in that same study, testosterone levels were raised significantly and both LH and FSH also went up slightly. (1)

In my mind, this is reason enough to suggest only using the stuff at a dose of .5mgs/day, as a preventative measure against water retention and gyno. If, however, you are trying to actually reduce pain from breast tissue which has already begun to hurt and show early signs of gyno, then you’ll have to use the full 1mg dose, even though it only provides a slight % more estrogen suppression.

When testosterone converts to estrogen in males, it feeds into the negative feedback loop that causes testosterone to cease being produced. Therefore, most compounds that will lower aromatization, such as an AI like Arimidex, will also raise testosterone by inhibition of the negative feedback loop that signals your body to halt testosterone production. In fact, in the case of Arimidex, the elevation in Testosterone provided by the inhibition of estrogen is so large that it can actually be used as a very mild form of testosterone replacement therapy for already hypogonadal men (2). Although, this points to its use in post-cycle-therapy, I hold the personal opinion that for numerous reasons Arimidex is best kept to use on a cycle, while Aromasin (exemestane) is a better choice in a post cycle recovery routing.

Blood plasma concentrations become stable by 7 consecutive 1mg daily doses, although maximal estrogen inhibition is reached by day 4. (3) Arimidex is over 80% effective at inhibiting the aromatase enzyme (3) and if you are considering using it for the entire duration of your cycle, then you don’t have to “front load” or even start it before the cycle as some have suggested. Simply start taking it on Day one of the cycle. Since the average cycle seems to fall around 12 weeks, Arimidex is actually a very nice choice for use during the entire duration of the cycle, because it’s got the advantage of not affect cholesterol adversely (2).

References:

1. J Clin Endocrinol Metab 2000 Jul;85(7):2370-7, " Estrogen Suppression in Males"

2. Clin Endocrinol (Oxf). 2005 Feb;62(2):228-35.

3. From Arimidex Package insert, Astra Zeneca Pharmaceuticals.

[D_IMURU]

Hi there,I haen't introduced myself yet.
I'm from Portugal,26y, and been training BB for a year now...still very newbie....
I have a question about nolvadex!!!!
I've been using it for 6-7weeks and I've experienced some great result with fat and water retention lose!But in this final week, 1.5week, i've noticed some retention coming!Why is that?do receptores saturate has well?shoul I increase de dosege or stop taking it...gibing it a break?
thank you all
*kisses*

[ms.karen]

Hey Sass: Question - so what if you're peri-menopausal? Would Nolva still be the weapon of choice if you're trying to get rid of estrogen fat? My upper body is unstoppable, but my hips and thighs are horrendous; they don't match at all. I carry all my weight there and I know it's the last to go, but I wouldn't mind "helping" it along :confused:.

[sassy69]

Hey Sass: Question - so what if you're peri-menopausal? Would Nolva still be the weapon of choice if you're trying to get rid of estrogen fat? My upper body is unstoppable, but my hips and thighs are horrendous; they don't match at all. I carry all my weight there and I know it's the last to go, but I wouldn't mind "helping" it along :confused:.

It will still help because you've still got ovarian estrogen imposing itself. But I guess just keep in mind that if you're new to the whole thing, you've had a lifetime of estrogen-driven fat depositing and now you're trying to even out the degree of leanness across your body. Diet will still be your number one tool to continue dropping bodyfat in your lower half (proportionately) even if your upper half already looks good. YOu can't pick and choose where you want to lose the fat. And further, it can take more than just one contest prep cycle to condition your lower half to not just lose the fat but get it used to staying near that way. This is often where you see people who do two shows back to back, they will come in w/ better conditioning at the second because they've held the conditioning from the first show instead of just letting things go back to "maintenance".

[ms.karen]

It will still help because you've still got ovarian estrogen imposing itself. But I guess just keep in mind that if you're new to the whole thing, you've had a lifetime of estrogen-driven fat depositing and now you're trying to even out the degree of leanness across your body. Diet will still be your number one tool to continue dropping bodyfat in your lower half (proportionately) even if your upper half already looks good. YOu can't pick and choose where you want to lose the fat. And further, it can take more than just one contest prep cycle to condition your lower half to not just lose the fat but get it used to staying near that way. This is often where you see people who do two shows back to back, they will come in w/ better conditioning at the second because they've held the conditioning from the first show instead of just letting things go back to "maintenance".

Thanks, that makes sense. I've had years of being overweight so it's gonna take some time for this to come off.

I still wish someone would just come up with a freaking pill that worked overnight. Hell, I'm not even picky, I'm willing to split it into TWO doses if it would work! :D

[sassy69]

Thanks, that makes sense. I've had years of being overweight so it's gonna take some time for this to come off.

I still wish someone would just come up with a freaking pill that worked overnight. Hell, I'm not even picky, I'm willing to split it into TWO doses if it would work! :D

The best you can do is just fuel your body for the way it was designed to work. Its a fantastically designed biochemical machine that WANTS to run efficiently!