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Parabolan (trenbolone hexahydrobenzylcarbonate)

Parabolan is one of those drugs which appeared briefly (Negma eventually pulled it off the market) and made a huge impact very quickly. Dan Duchaine was the first person to write about this compound in his Underground Steroid Handbook Update Newsletter. In his write up, he speculated that you wouldnt want to go over 2 amps per week of the Original Negma Product (each amp was 76mgs, and if you are wondering why thats so, its because each amp gave the user precisely 50mgs of Trenbolone, once your bodys esterases cleave off the HexaHydroBencyl Carbonate ester ). Unfortunately, not many people really got a chance to experiment with the original Parabolan, as it was pulled off the market very quickly by Negma (discontinued in 1997). That created a very odd situation where the product was used very successfully by a few people for a very short time, then was basically unavailable after that. This basically created a bit of a cult following for the drug. Decades passed, and counterfeits stormed the market until Duchaine (again) wrote an article on extracting the Trenbolone from Finaplex Pellets, and then sterilizing them, in order to create your own Trenbolone Acetate, although this wasnt Parabolan, it soon curtailed the counterfeit craze for Parabolan. Tren was Tren, in most peoples eyes, regardless of the ester. "Fina kits" (a kit which enabled the user to make their own tren) then flooded the market, utilizing a loophole whereby the pellets and kit were both legal to buy, although clearly, making and using an injectable steroid in your kitchen is illegal. Flashing forward a few years, Trenbolone Acetate became available by many Underground Labs, then Trenbolone Enanthate became available, and now, even Parabolan (which is Trenbolone Base + a HexaHydroBencyl Carbonate Ester) is easily obtained from most major Underground Labs. A visit to or any of the major discussion boards will testify that Parabolans cult following still hasnt diminished. Lets see why.

Parabolan is neither affected by aromatase or 5alpha-reductase. This means it becomes neither weaker nor stronger in androgen responsive target tissues, and is a trait usually shared by DHT (DyhydroTestosterone) derived steroids; Since Parabolan is of course a Trenbolone, it is not actually DHT derived but rather, it is derived from 19-Nor-Testosterone.. Parabolan has no estrogenic activity (it may actually reduce serum estradiol levels in the body), is a very strong anabolic and androgenic compound (5x stronger than testosterone in both categories!), and it binds well to the androgen receptor. Actually, binding "well" to the androgen receptor is quite an understatement. Theres no injectable AAS in our arsenal that binds to the androgen receptor (AR) as well as Trenbolone does. This is probably a major reason that Parabolan was so saught after for use as a precontest agent. Androgen Receptors are found in fat cells as well as muscle cells(8), and we all know that they act on the AR in muscle cells to promote growth, but they androgens act directly on the AR in fat cells to affect fat burning.(9)(6) The stronger the androgen binds to the A.R, the higher the lipolytic (fat burning) effect on adipose (fat)tissue(9)(5). As if thats not enough good news, some steroids even increase the numbers of A.R. in muscle and fat (9)(10), leading me to speculate that this fat losing effect would be amplified with the concurrent use of other compounds, such as injectable testosterone.

clenbuterol,steroids,clen Another mechanism whereby Parabolan causes muscle accumulation and fat loss is its ability as a nutrient partitioning agent.(7) Basically, what this means is that while using Tren, more of the food you eat will become Muscle and less (if any) will become Fat. Really, as you can see, most of Parabolans cult reputation is well deserved... And as if thats not enough, Parabolan noticeably increases the level of the IGF-1 within muscle tissue (2), which in itself is an extremely anabolic hormone. And, its worth noting that not only does it increase the levels of IGF-1 in muscle over two fold (2), it also causes muscle satellite cells (cells that repair damaged muscle) to be more sensitive to IGF-1 and other growth factors(3). This leads me to speculate that Parabolan (or any version of Tren) would be synergistic within a cycle containing any form of injectable IGF-1.

Parabolan also happens to bind quite strongly to the glucocorticoid receptor as well, and this in turn imparts a nice anti-catabolic effect... which in part may help to explain why low(ish) doses of it seem to work nicely, as well as why it aids fat loss. You see, glucocorticoid hormones send a message to muscle cells to release stored protein (this is called catabolism), which is exactly the opposite of what we want.

This drug stacks well with mostly everything especially Testosterone (actually, if you want to avoid sexual dysfunction, stacking it with test is necessary). I have also found it to be a great addition to a stack containing Eq as well, unfortunately the insomnia the Parabolan gives me added to the appetite the Eq gives me makes midnight snacking almost inevitable. Parabolan is most often used in cutting stacks when "quality muscle" gain is favored over bloat and water retention. Really, I think Parabolan (or any Tren) is a great "cutting" anabolic, although it has been used successfully by many in both Cutting and Bulking cycles.

Its not all good news, though...

Parabolan Side Effects

Some users of Para report sexual Dysfunction (Tren-Dick) and symptoms of Gyno (probably progesterone related, as Trenbolone acts on progesterone receptor but not the estrogen receptor). As you know, Trenbolone is unfortunately, a progestin: it binds to the receptor of the female sex hormone progesterone (with about 60% of the actual strength progesterone) (4). In hyper-sentitive members this can lead to bloat and breast growth when combined with an estrogenic or aromatizable product, but probably not with out one (14); worse still, Trenbolones active metabolite (17beta-trenbolone) has a binding affinity to the progesterone receptor that is actually greater than progesterone itself (5). No need to panic though, the aromatase inhibitor Lertrozole can also lower progesterone levels, and combat any progestenic sides (15)(16). I would strongly consider its inclusion at .25-.5mgs/day in a cycle containing Parabolan or any 19-nor compound.

Ironically, even though Para is an excellent cutting drug, it will lower your thyroid level (11). Doing this, by means of the bodys negative-feedback-loop, also raises prolactin. Ergo, I recommend taking T3 (25mcgs/day) along with your Tren to avoid suffering from increased levels of prolactin and the host of unwanted side effects this could cause. For these reasons, many people avoid stacking Tren with Deca (Nandrolone Decanoate), which is also a progestin (4).

Mental changes are a notorious side effect of any type of trenbolone use (12), and Para is no exception to this rule. Androgens increase chemicals in the brain that promote aggressive behavior(13), which can be beneficial for some athletes wanting to improve speed and power, but perhaps detrimental to those trying to hold a job as a social worker. Luckily, I am not generally known for being an ambassador of goodwill usually, so this side effect goes largely unnoticed in me.

For me, the worst effect of any sort of Trenbolone is "Tren cough" which I get for the first 2 weeks of my cycle, when it includes this compound. Tren Enanthate does not have this effect on me, but Parabolan sometimes does; Tren Acetate gives me a crippling Tren-Cough for the first week or so that Im on it. Also, any kind of Tren gives me a bit of insomnia, which is common for many users. The most noticeable side effect of Parabolan for me is that it increases my sweating dramatically, even giving me vicious "night sweats" that go nicely with my insomnia. Walking up a flight of stairs can also cause me to break out in beads of sweat when Im on this product. Also, it needs to be noted that many people experience a reduced cardiovascular capacity when using Para (12), and I fall into this category as well. Still, its incredible effects on my strength and appearance mean that itll fall into my cycles for off seasons and in the winter (when sweating wont be as much of a problem).

Parabolan Profile

  • (Trenbolone Base + HexaHydroBencyl Carbonate Ester)
  • [17beta-Hydroxyestra-4,9,11-trien-3-one]
  • Formula: C20 H24 O3
  • Molecular Weight (base): 270.3706
  • Molecular Weight (ester):130.1864
  • Formula (base): C18 H22 O2
  • Melting Point (base): 183-186C
  • Manufacturer: (originally) Negma, Various Underground Labs
  • Effective Dose (Men): 300-500mgs/week
  • Effective Dose (Women): Not recommended
  • Active life: 5-7 days
  • Detection Time: 4-5 weeks
  • Anabolic/Androgenic ratio: 500/500

Parabolan References:

  1. Br J Nutr. 1978 Nov;40(3):563-72.
  2. J Cell Physiol. 2004 Nov;201(2):181-9.
  3. Endocrinology. 1989 May;124(5):2110-7.
  4. Cancer Res 1978 Nov; 38(11 Pt 2):4186-98
  5. APMIS. 2000 Dec;108(12):838-46.
  6. (Xu X, et al. "The effects of androgens on the regulation of lipolysis in adipose precursor cells." Endocrinology 1990 Feb;126(2):1229 ).
  7. J Anim Sci. 1992 Nov;70(11):3381-90.
  8. Am J Physiol. 1998 Jun;274(6 Pt 1):C1645-52.
  9. Biochim Biophys Acta. 1995 May 11;1244(1):117-20.
  10. J Appl. Physiol.94 1153-61 2003
  11. Res Vet Sci 1981 Jan;30(1):7-13
  12. forums.
  13. Med Sci Sports Exerc. 2003 Jan; 35(1):32-8
  14. Progesterone is not essential to the differentiative potential of mammary epithelium in the male mouse. Freeman, Topper. Endocrinology. 1978 Jul;103(1):186-92
  15. Eur J Obstet Gynecol Reprod Biol. 2002 Nov 15;105(2):161-5.
  16. J Clin Endocrinol Metab. 1995 Sep;80(9):2658-60.

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