Nandrolone decanoate was first described in 1960 and was first used in medicine in 1962. The Organon firm began to produce it, and sold it under the brand name of the Deca Durabolin. This name means that this product contains a variety of previously popular Nandrolone - Durabolin (phenylpropionate) with ether of the ten carbon atoms.

Because of Organon, nandrolone decanoate has become one of the most widely used injectable steroids in the world. It was prescribed for the treatment of many diseases. It was used for the treatment of dystrophy, osteoporosis, breast cancer, malnutrition, severe injuries, anemia and the growth retardation of children. Initially, the drug was produced in a concentration of 50 mg \ ml, then emerged versions with concentrations of 100 mg \ ml and 200 mg \ ml. After 1975, its scope was reduced, but not by much. Deca Durabolin by Organon is widely available in our time. Furthermore, Nandrolone decanoate is produced by a variety of firms under a variety of brand names.

Chemical structure

Nandrolone decanoate – it is a modified form of Nandrolone, in which the decanoate ether is attached to nandrolone through 17-beta hydroxy group. Esterified steroids are less polar than the free steroids and are soaked up more slowly from the injection area. Getting into the bloodstream, the ether is cleaved off and the free nandrolone is released into the bloodstream. Esterified steroids have been developed in order to prolong the therapeutic effect after the injection and to inject less frequently compared to injections of free steroids.  Nandrolone decanoate (Deca) was developed to provide a prolonged excretion of nandrolone within 4 weeks after injection.


  • Anabolic activity - 150% of testosterone
  • Androgenic activity - 30% of testosterone
  • Aromatization (conversion into estrogens) - minimal
  • Toxicity to the liver - low
  • Type - injections
  • The duration of action - 15 days
  • Recommended dosage - 200-400 mg per week
  • The detection time - up to 18 months
  • Suppression of the testosterone - average-high (due to the nature of the progestin)


  • Noticeable muscle growth (in one course you can gain up to 8 kg (16 lbs) of muscle mass with a minimal rollback phenomenon)
  • Strengthening of bones (previously was used to treat osteoporosis) and ligaments (stimulates collagen synthesis)
  • Elimination of joint pains, due to increase of production of synovial fluid (joint lubricant)
  • The increase of red blood cell mass, which improves the oxygen transport
  • Increase of immune protection (applies even to people with AIDS)

Nandrolone (Deca) has a relatively low likelihood of side effects. As a result of low androgenic activity, such side effects as acne, baldness and body hair growth almost never occur. Nevertheless, they are possible, as in the use of any steroid; but in the case of nandrolone this only happens when the recommended doses are exceeded in several times.

Retabolil has a very low conversion rate to estrogens, research has shown - 5 times lower than testosterone. The highest level of conversion is observed in the liver, while the main place where the transformation takes place (adipose tissue) is still inaccessible to this process. As a consequence, Deca Durabolin has no side effects connected with estrogen (gynecomastia, a buildup of fluid in the body). Estrogenic activity of the drug is manifested only at very high doses.

The aforementioned characteristics explain why Deca Durabolin is one of the most popular anabolic steroids to the present time, including for the men for the purpose of gaining lean muscle. Moreover, it is necessary to add that nandrolone practically does not cause a phenomenon of rollback.

Side effects

It has been observed that Nandrolone is able to bind to progestin receptors (approximately 20% of the injected material), it is connected with removal of the carbon atom in the 19th position. Almost all of the 19-nor anabolic steroids are showing progestin activity.

In addition, in research retabolil (Deca) caused the following side effects:

  • Headache - 20%
  • Rhinitis (runny nose)- 15%
  • Backache - 15%
  • Rashes - 10%

Besides, during the course sometimes occur: the rise of blood pressure, abdominal pain, irritability, headaches, depression and some other complications.

Dosages and Uses

Dosages: from 200 mg per week. In exceptional cases - 800 mg per day (for the professionals of the highest level).

The frequency of dosing: from twice a week to daily doses

Effective doses of nandrolone (deca) are beginning with 200 mg per week and are pretty much endless. There are cases of application of nandrolone decanoate by professional level athletes in dosages of about 800 mg per day. However, it is necessary to say that in recent times professional athletes refuse to use Nandrolone, believing this drug is, so to say, time-worn. You should not bother with such doses - most of you will hardly ever reach the professional level - the upper limit of consumption of nandrolone is set to 1 gram per week.

On the basis of a sufficiently long half-life of nandrolone decanoate, it is possible to recommend its injections once every 7-8 days, although there are supporters of more frequent injections, even long-lived products - so you can provide a more stable level of steroid in the blood.

Cycles (Courses)

  • The course of nandrolone (Deca) generally lasts for 8-10 weeks, at the same time, there are not uncommon cases when performing athletes use it up to six months, gradually increasing the dosage.
  • Injections of Retabolilum are usually done 1 time per week. Considering the activity period - 15 days, there is no need to do 2 injections of Retabolilum per week. But if the weekly injection volume is large, often it is divided into two or three injections. 

Combined courses

  • Winstrol is well combined with the drug.
  • Testosterone - typically is used 200-400 mg of Retabolilum (1 time per week), and, respectively, 250-750 mg of testosterone per week.
  • Sustanon - 200-400 mg of Retabolilum 1 time per week, and 250-750 mg of Sustanon per week.
  • Methandrostenolone - 200-400 mg of Retabolilum 1 time per week, and 10-50 mg of methandrostenolone every day, in combination with testosterone.