Nandrolone decanoate is an injectable form of the anabolic steroid nandrolone. The decanoate ester provides a slow release of nandrolone from the site of injection, lasting for up to three weeks. Nandrolone is very similar to testosterone in structure, although it lacks a carbon atom at the 19th position (hence its other name, 19- nortestosterone). Like testosterone, nandrolone exhibits relatively strong anabolic properties. Unlike testosterone, however, its tissue-building activity is accompanied by weak androgenic properties. Much of this has to do with the reduction of nandrolone to a weaker steroid, dihydronandrolone, in the same androgen responsive target tissues that potentate the action of testosterone (by converting it to DHT). The mild properties of nandrolone decanoate have made it one of the most popular injectable steroids worldwide, highly favored by athletes for its ability to promote significant strength and lean muscle mass gains without strong androgenic or estrogenic side effects.

History:

Nandrolone decanoate was first described in 1960, and became a prescription medication in 1962. It was developed by the international pharmaceuticals giant Organon, and sold under the brand name Deca-Durabolin. The name Deca- Durabolin denotes that the product contains a variant of Organon’s previously popular nandrolone injectable Durabolin (nandrolone phenylpropionate) using an ester of 10 carbon atoms. Organon expanded the market for nandrolone decanoate very rapidly following its release. Probably owing to a combination of its favorable properties and the large market presence of Organon, Deca-Durabolin soon became one of the most widely distributed anabolic steroids in the world.

Structural Characteristics:

Nandrolone decanoate is a modified form of nandrolone, where a carboxylic acid ester (decanoic acid) has been attached to the 17-beta hydroxyl group. Esterified steroids are less polar than free steroids, and are absorbed more slowly from the area of injection. Once in the bloodstream, the ester is removed to yield free (active) nandrolone.

Esterified steroids are designed to prolong the window of therapeutic effect following administration, allowing for a less frequent injection schedule compared to injections of free (unesterified) steroid. Nandrolone decanoate provides a sharp spike in nandrolone release 24-48 hours following deep intramuscular injection, which steadily declines to near baseline levels approximately two weeks later. The half-life of nandrolone decanoate is 7-12 days.

Side Effects (Estrogenic):

Nandrolone has a low tendency for estrogen conversion, estimated to be only about 20% of that seen with testosterone. This is because while the liver can convert nandrolone to estradiol, in other more active sites of steroid aromatization such as adipose tissue nandrolone is far less open to this process. Consequently, estrogen-related side effects are a much lower concern with this drug than with testosterone. Elevated estrogen levels may still be noticed with higher dosing, however, and may cause side effects such as increased water retention, body fat gain, and gynecomastia. An anti-estrogen such as clomiphene citrate or tamoxifen citrate may be necessary to prevent estrogenic side effects if they occur. One may alternately use an aromatase inhibitor like Arimidex® (anastrozole), which more efficiently controls estrogen by preventing its synthesis. Aromatase inhibitors can be quite expensive in comparison to anti-estrogens, however, and may also have negative effects on blood lipids.

Side Effects (Androgenic):

Although classified as an anabolic steroid, androgenic side effects are still possible with this substance, especially with higher doses. This may include bouts of oily skin, acne, and body/facial hair growth. Anabolic/androgenic steroids may also aggravate male pattern hair loss. Women are warned of the potential virilizing effects of anabolic/androgenic steroids. These may include a deepening of the voice, menstrual irregularities, changes in skin texture, facial hair growth, and clitoral enlargement. Nandrolone is a steroid with relatively low androgenic activity relative to its tissuebuilding actions, making the threshold for strong androgenic side effects comparably higher than with more androgenic agents such as testosterone, methandrostenolone, or fluoxymesterone. It is also important to point out that due to its mild androgenic nature and ability to suppress endogenous testosterone, nandrolone is prone to interfering with libido in males when used without another androgen.

Note that in androgen-responsive target tissues such as the skin, scalp, and prostate, the relative androgenicity of nandrolone is reduced by its reduction to dihydronandrolone (DHN).  The 5-alpha reductase enzyme is responsible for this metabolism of nandrolone. The concurrent use of a 5- alpha reductase inhibitor such as finasteride or dutasteride will interfere with site-specific reduction of nandrolone action, considerably increasing the tendency of nandrolone to produce androgenic side effects. Reductase inhibitors should be avoided with nandrolone if low androgenicity is desired.

Side Effects (Hepatotoxicity):

Nandrolone is not c-17 alpha alkylated, and not known to have hepatotoxic effects in healthy subjects. Liver toxicity is unlikely.

Technical

•    (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): 122-124C
•    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