(Nandrolone Base + Decanoate Ester)
    [19-nor-androst-4-en-3-one-17beta-ol]
    Molecular Weight(base):274.4022
    Molecular Weight (ester):172.2668
    Formula (base): C18 H26 O2
    Formula (ester):C10 H20 O2
    Melting Point (base): 122-124°C
    Melting Point (ester):31 - 32 C
    Manufacturer: Organon
    Release Date (in USA): 1962
    Effective Dose (Men): 200-600mgs/week (2mg/lb of Bodyweight)
    Effective Dose (Women): 50-100mgs/week
    Active life: 15 days
    Detection Time: Up to 18 months
    Anabolic/Androgenic ratio: 125:37

Deca - Durabolin ("Deca") is actually the brand name for Organon´s version of the compound Nandrolone Decanoate. This is a 19-Nor compound (some would say that it is the 19-nor compound), and as such, it shares basically the same characteristics with all of them. One thing unique to Deca, above nearly all steroids, is the mystique it has had for the last quarter of a century. On a personal level, I´ve included Deca in cycles at doses ranging from 100mgs/week to 2,000mgs per week. Suffice to say, I have my fair share of experience with this compound. This drug was regarded very highly by Dan Duchaine in his Underground Steroid Handbooks as well as many of his later writings. For many, this was and is the final word on Deca. Let´s delve into some of the reasons that Deca´s mystique may be well deserved.

First of all, Deca (and Nandrolone in general) doesn´t produce many estrogenic or androgenic side effects. This is because Deca has a very low rate of aromatization (conversion to estrogen via the aromatase enzyme), roughly equal to 20% the rate of Testosterone.

Also, I´ve read many places that Deca stores water in connective tissue, thus alleviating joint pain. I have no idea what "storing water in the joints" means. I have no idea how to really quantify that statement, or where it started. However, in one study of postmenapusal women, Deca impoved collagen synthesis (1), and in another study deca increased bone mineral content. (2)Both of these studies used VERY low doses, which were far too low to promote muscle growth. In my estimation, based on these 2 studies, an athlete attempting to use Deca only for these two effects (increasing bone mineral content and collagen synthesis) should be using 100mgs of deca every week. That´s actually a higher dose than those two studies used successfully. Even at ½ of this dose, in HIV+ patients who have experienced significant wasting, a 100mg/E2W (every 2 weeks) injection of Deca resulted in a "significant increase in weight" (5). I´d never recommend that low of a dose for an athlete, but it´s evidence of Deca´s strong anabolic properties. Deca is a very nice anabolic, causing nice (albeit slow) gains in quality muscle. This could be due to its moderately strong binding to the Androgen Receptor, or its many positive non-Androgen-Receptor mediated effects. One such effect is nitrogen retention, which is a major factor in muscle growth and lean mass gains; in one study, with low-doses (65 mg/week) and high-doses of Deca (200 mg/week), both low-doses and high-doses resulted in significant nitrogen retention (33-52 g nitrogen/14 days, representing gains of 0.5 to 0.9 kg lean tissue/week), and body weight increased by 4.9 +/- 1.2 kg, including 3.1 +/- 0.5 kg lean body mass, and treadmill exercise performance (cardiovascular fitness) also improved (7). Need I say that the higher doses in this study produced more gains? Steroid.com members who have posted their results with deca confirm this in many posts and threads, with their average reccomendation being to take 400-600mgs/week for muscle gain. I have to agree.

Deca also has a very long active life. We can see from the chart below that a 100mg shot Deca (represented by the circles) produced relatively active and stable plasma nandrolone levels until day almost 10, hence once a week shots are all that´s necessary for stable levels of nandrolond decanoate (as a side note, the nandrolone phenylpropionate used in this study was active, and only experienced a severe drop off around day 5, shooting NPP every 4th day is the way to go). You´ll also note that higher blood plasma levels of Nandrolone are found with Gluteal injections as opposed to Deltoid injections (this is true for all oil-based steroids, I suspect).

In another study of HIV+ men (6) we can see that deca ( 200mgs on week 1, 400 on week 2 and 600mgs for weeks 3-12) caused NO negative side effects in total or LDL cholesterol, triglycerides, or insulin sensitivity and there was a reduction of HDL cholesterol(8-10 points) in both groups. Also, in most studies with HIV+ subjects, deca also improved immune function.

So what do we know so far about this compound? So far, we know that Deca is a very safe drug for long term use, will help with joint problems, could improve immune function, and is highly (!) anabolic, and not very androgenic.

That´s the good news (and there´s a lot of it), now for the bad news:

Deca is known for producing quality weight gains, but it has to be used for 12 weeks at a minimum, judging from Steroid.com members´ feedback, as well as my own personal experience. This shouldn´t cause any problems, since it is a very mild drug in terms of side-effects.

Many members of Steroid.com also complain of water-retention with this drug, and again, I´m inclined to agree. Letrozole seems to be a preferred choice to combat this, and it´s my favorite for this use. This water retention would seem to make Deca more suitable for bulking rather than cutting, although it can be successfully used for either.

Now for the worst news: Deca is a progestin (as are all nandrolones), unfortunately; it happens to stimulate the progesterone receptor 20% as well as progesterone itself (3), and this opens the door for many possible unwanted side effects (water retention, acne, etc...). It must be noted that most of those are rare, though. This also may be the major reason that Deca is such a suppressive drug when it comes to your natural testosterone levels. We can see from the chart below that a simgle measly 100mg injection of Deca caused a total (100%) reduction of natural testosterone levels, and it took roughly a month to return those testosterone levels to baseline! All from 100mgs of Deca!

The moral of this story? Always use Testosterone with your Deca! I suggest 200mgs, minimum, to avoid impotence and sexual dysfunction. For an anabolic effect from that Testosterone, I recommend at least double that, with an equal amount of deca (minimum). I´d also recommend taking an anti-progesteronic drug with deca (or at least having it on hand): Cabergoline and Bromocriptine are both good choices.

So where are we? Well, I´d be comfortable recommending Deca for use in a bulking cycle at up to 600mgs/week for an extended duration (12-16 weeks), or up to 400mgs/week in a cutting cycle (again, for 12-16 weeks), as long as something to combat water retention is present. Whichever purpose you decide to use Deca for, you still need to include Testosterone in your cycle and have some anti-progesteronic drugs on hand (see paragraph above), just in case.

Post Cycle Therapy (PCT), though beyond the scope of this profile, needs to be commented on. Due to the highly suppressive nature of Deca, I will speculate that testosterone in a deca-inclusive cycle needs to be run for at least 2 additional weeks upon cessation of Deca. We remember from the chart above that baseline testosterone levels took roughly a month to return. Hence, a nice long estered testosterone should be run about 2 weeks longer than deca, to prevent having a lag in time when the deca is not producing an anabolic effect, yet is still suppressing your natural testosterone levels. I´d also suggest that a particularly aggressive PCT be run after your cycle; nolvadex, HCG, and perhaps clomid should all be utilized in an effort to restore your natural hormone levels as quickly and efficiently as possible.

1.    Metabolism. 1990 Nov;39(11):1167-9

2.    Effects of nandrolone decanoate on bone mineral content R, Righi GA, Turchetti V, Vattimo A.).

3.    Cancer Res 1978 Nov;38(11 Pt 2):4186-98

4.    (Charts) from Minto et al

5.    AIDS. 1996 Jun;10(7):745-52

6.    Sattler et al. Am J Physiol Endocrinol Metab 283: e1214-22

7.    J Acquir Immune Defic Syndr Hum Retrovirol. 1999 Feb 1;20(2):137-46.