Testosterone + Undecanoate ester
Molecular weight of base: 288.429
Molecular weight of ester: 186.2936
Formula: C19 H28 O2
Melting Point: 155
Effective dose: 600mgs
Active Life: less than 8-12 hours
Detection Time: 4-5 weeks
Anabolic/Androgenic Ratio (Range):
Undestor is testosterone with the undecanoate ester attached, and
produced in oral form. It represents the first real attempt to create an oral
testosterone since Methyl testosterone. I can only assume that the scientists
responsible for this wanted to create a viable alternative to both injectable
testosterones (which, at least for Hormone Replacement Therapy, is
inconvenient), as well as other oral forms of testosterone (which have
traditionally been very harsh on the liver). What they came up with has proven
to be a very odd steroid in many ways.
To create Andriol, the scientists involved had to come up with a solution to
the problems facing methyltestosterone, namely the fact that it is
harsh on the liver and needs to be taken in very high doses to produce decent
results. What they did was put 40mgs of Testosterone
Undecanoate in oleic acid (an oil), and encapsulate it. Now they use castor
oil and propylene glycol laurate instead of oleic acid, but that only increases
the shelf life, and doesnt do anything else. For some of the aspiring chemists
reading this, you may be asking yourself the obvious question. And the answer
is yes, you can take almost any estrified drug (Nandrolone
Decanoate, for example), and dissolve it in castor oil and propelyne glycol
laurate, and create your own "Deca Caps"
or whatever. The problem is that youd need to be able to make sealed gel caps,
not just the typical 2-part capsules most people throw steroid powder in.
Anyway, Im digressing; lets get back to Undestor. After you put some
testosterone undecanoate in caster oil and propelyne glycol laurate, youll have
a testosterone which is highly fat-soluble due to the (very large) undecanoate
ester attached to it, and able to be absorbed through your small intestine via
the lymphatic system. What this means is that it avoids the "first
pass" through the liver, a process which could destroy much of the active
steroid, and place an undue amount of stress on the liver. It also displayed a
rapid absorption and turnover in one study(11), which may account for its
ability to not cause unwanted side effects . Its not bad for your blood
pressure (13), and also has no adverse effects on the prostate and may even
improve blood pressure(12)! Thus, Undestor is remarkably light on all
side effects, especially those related to liver toxicity and estrogenic sides.
Undestor for Women
In this study, done with women, it even displayed no ability to lower LH and
FSH (Leutenizing Hormone and Follicle Stimulating Hormone, respectively), which
are the hormones that tell your body to make more testosterone (11). I doubt Undestor
could be properly regarded as liver toxic or too damaging to your HPTA
(Hypothalamus-Pituitary-Testicular-Axis, the thing that governs your bodys
production of testosterone, among other things). at any kind of reasonable (or
even excessive) dose. Actually, one study noted no adverse reactions or effects
at all with the use of Undestor (10). As for your lipid profile and
cholesterol, it has even been shown to have beneficial effects on them (14)!
So, putting some Testosterone Undecanoate in Gel Caps is what the scientists
at Organon have done with their Undestor product, and it all looks
good so far, right? The active steroid totally bypasses your liver and hence
doesnt get damaged by or damage your liver, and gets a bunch of Testosterone
into your body. Great! But what happens next? Well, after the lymphatic system
has brought the testosterone undecanoate into circulation in your body, the
undecanoate ester begins to be removed. This would leave you with (roughly)
25mgs of testosterone in your blood stream, as the decanoate ester takes up a
lot of "space" and the cap only contains a total of 40mgs of
testosterone undecanoate (roughly 15mgs of which are ester). The end results
from Undestor would be very similar to the end result of injecting
almost any form of testosterone (4), once your body removes the ester. But
remember, youd never inject 25mgs of testosterone suspension and call it a day,
but thats exactly what you are doing when you take only one Andriol cap.
So now you have 25mgs of testosterone floating around in your body. Thats
not much, so if youre realistically considering using this product, youll need
to take quite a few caps of this it. And theres one of the first problems we
encounter with this drug. You see, the method of administration of this drug
provides us with a nice liver-safe product, but this stuff will peak your
testosterone levels within around 2 hours after administration, and will only
remain (at least slightly) elevated for 10 or so hours(1). Ideally, youd be
taking a capsule every 2 hours, which is inconvenient to say the least. Lets be
generous and say you can simply take one every 4 hours. Problem solved? Not
really, because were going to need to take at least 2 caps with each dose if we
want to see any sort of anabolic effect, and if were taking it every 4 hours
(assuming were awake for 16hrs every day), then well be taking around 8 caps
per day. Now weve shifted the problem away from the effort needed to take an
effective does to being a problem with economics.
Cost to Buy Undestor
The problem with type of dose is going to be cost to buy andriol. Undestor
is pretty expensive to be taking in the amount of 8 caps per day, and I have
never seen it made by anyone except for Organon& which means we wont find
it on any UnderGround Labs product lists. And that means we need to pay
whatever price Organon is asking...and they are asking a lot. You can easily
run a cycle with several very anabolic compounds for the price of a cycle of
So thats our major obstacle, the expense of taking Undestor in what
would be an effective dose is prohibitive to most people. One study noted that Undestor
therapy, when compared with traditional Testosterone injections is roughly 7-8x
more expensive (5).
Undestor Side Effects
Cost not withstanding, lets see what kind of Undestor side effects
we can expect (besides the catabolic effect it will have on your wallet).
Although it has a reputation for being very mild, youll still see some results
from Undestor. One study using a very low dose on adolescent boys
still showed a reasonable gain in Fat Free Mass(3) even though the boys were
not training. And in another study focusing on the elderly, it improved their
quality of life considerably (as androgens often do) (6), and also had
beneficial effects on erectile dysfunction (7) (again, this is typical of
androgens). This is certainly promising, but in a world where first time-ste In
fact, it may even be a useful adjunct with Viagra for this purpose (8).
However, in a world where first time steroid users expect upwards of 20lbs per
cycle, I would suspect many will be disappointed with the 5lbs or so a cycle of
Andriol will produce. Granted, thats a conservative estimate, but I cant really
be confident predicting much more muscle is to be expected from Undestor.
Taking a large amount of Undestor is actually pretty safe (except for
your bank account), and there was even a 3 month study done in Korea, where a
pretty small dose of Undestor ( 160 mg daily for 3 weeks then half
that dose for the remainder of the study) resulted in a very nice rise in
testosterone. Serum total testosterone increased from 2.13 +/- 1.20 ng/ml at
baseline to 6.04 +/- 3.08 ng/ml (p = 0.005) after 12 weeks. In addition, free
testosterone was (barely) significantly changed from 8.60 +/- 2.25 pg/ml to
11.40 +/- 3.81 pg/ml (p = 0.13) (10). However, there were no significant
changes in liver function tests, red blood cell count or lipid profiles, nor
were there any significant adverse reactions that would have led to the
cessation of the administration of oral testosterone. So the scientists at
Organon have succeeded in making a nice, safe, moderately effective orally
available treatment for low androgen levels. But can we (athletes and
bodybuilders) use it also?
Truthfully, I cant be confident predicting more than a 5lbs gain with the
use of Undestor, because this product has a very odd property, and
that is the widely varying effects it has on test subjects. In one
study I read, four test subjects were each given Undestor, and one had
a huge surge in testosterone levels going up to 60.1nmol/L and the other only
had a 11.5nmol/L level(5)! The remaining 2 test subjects fell in between those
levels. I am speculating that the differences experienced by the test subjects
were primarily due to the variances inherent in the lymphatic system. But to
make matters even more inconsistent, there is no evidence that those variances
wouldnt occur within the same person taking Undestor (i.e. you get a
huge surge in testosterone one day, and a very minor one the next day). This
may be due to variability associated with whether this stuff is taken with food
or not. Since it operates via association with your small intestine and
lymphatic pathways, taking it with food greatly enhances its bioavailability
(9), and this may be a case of "problem solved" but Im hesitant to
close the books on andriols absorption problems so quickly, for now, well just
say you are spending your money much more wisely if you take your andriol with
Despite all of its problems, if I had the money to run 10-15 caps of Undestor/day,
and if I were looking for a stand-alone oral compound to safely run for a full
cycle (of perhaps 12 weeks), then I have to admit, Undestor would be
my #1 choice.
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