Anabol 4-19 (norclostebol acetate)

Description:

Norclostebol acetate is an anabolic steroid that is derived from nandrolone. It is specifically a 4-chloro derivative, further modified with an acetate ester to slightly slow the release of free steroid from the site of injection. An oral form of the same drug was also made, owing to the fact that 4-chloro substitution increases oral bioavailability to some extent. Norclostebol acetate assays out to be very strong compared to testosterone, with approximately 6.6 times the anabolic potency and 40% of the androgenicity. Comparisons to testosterone propionate, perhaps more valid given the use of an ester, put this steroid at about equal in anabolic potency (112%), with only 20-25% of the androgenicity. Although the exact real-world relevance of these figures remains to be seen, when put into use this agent is very likely to behave as a favorable and primarily anabolic drug, with a low tendency to produce side effects.

History:

Norclostebol acetate was first described in 1956.1 It was developed into a medicine by Piam, which sold it briefly decades ago under the trade name Anabol 4-19. The 4-19 referred to the unique structural modifications to the steroid, namely that it was a 4chloro 19-nortestosterone (nandrolone) derivative. Like its cousin Megagrisevit (clostebol acetate), norclostebol acetate was manufactured in both oral and injectable forms. The drug was ultimately less successful than even Megagrisevit (which also was a poor performer internationally), probably because it was developed during a very competitive time in the industry, when many effective agents were vying for pharmacy dollars. Anabol 419 was abandoned by the manufacturer many years ago, and has been unavailable for so long that few athletes have any memory of it.

How Supplied:

Norclostebol acetate is no longer available as a commercial agent.

Structural Characteristics:

Norclostebol is a modified form of nandrolone. It differs by the introduction of a hydroxyl group at carbon 4, which inhibits aromatization and reduces relative steroid androgenicity. Norclostebol acetate contains norclostebol modified with the addition of carboxylic acid ester (acetic acid) at the 17-beta hydroxyl group, so that the free steroid is released more slowly from the area of injection.

Side Effects (Estrogenic):

Norclostebol is not aromatized by the body, and is not measurably estrogenic. An anti-estrogen is not necessary when using this steroid, as gynecomastia should not be a concern even among sensitive individuals. Since estrogen is the usual culprit with water retention, norclostebol instead produces a lean, quality look to the physique with no fear of excess subcutaneous fluid retention. This makes it a favorable steroid to use during cutting cycles, when water and fat retention are major concerns.

Side Effects (Androgenic):

Although classified as an anabolic steroid, androgenic side effects are still possible with this substance. 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 also 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. Additionally, norclostebol is not extensively metabolized by the 5-alpha reductase enzyme, so its relative androgenicity is not greatly altered by the concurrent use of finasteride or dutasteride. Note that norclostebol 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.

Side Effects (Hepatotoxicity):

Norclostebol is not a c17-alpha alkylated compound, and not known to have hepatotoxic effects. Liver toxicity is unlikely.

Side Effects (Cardiovascular):

Anabolic/androgenic steroids can have deleterious effects on serum cholesterol. This includes a tendency to reduce HDL (good) cholesterol values and increase LDL (bad) cholesterol values, which may shift the HDL to LDL balance in a direction that favors greater risk of arteriosclerosis. The relative impact of an anabolic/androgenic steroid on serum lipids is dependant on the dose, route of administration (oral vs. injectable), type of steroid (aromatizable or non-aromatizable), and level of resistance to hepatic metabolism. Norclostebol should have a stronger negative effect on the hepatic management of cholesterol than testosterone or nandrolone due to its non-aromatizable nature, but a much weaker impact than c-17 alpha alkylated steroids. Anabolic/androgenic steroids may also adversely effect blood pressure and triglycerides, reduce endothelial relaxation, and support left ventricular hypertrophy, all potentially increasing the risk of cardiovascular disease and myocardial infarction.

To help reduce cardiovascular strain it is advised to maintain an active cardiovascular exercise program and minimize the intake of saturated fats, cholesterol, and simple carbohydrates at all times during active AAS administration. Supplementing with fish oils (4 grams per day) and a natural cholesterol/antioxidant formula such as Lipid Stabil or a product with comparable ingredients is also recommended.

Side Effects (Testosterone Suppression):

All anabolic/androgenic steroids when taken in doses sufficient to promote muscle gain are expected to suppress endogenous testosterone production. Without the intervention of testosterone stimulating substances, testosterone levels should return to normal within 1-4 months of drug secession. Note that prolonged hypogonadotrophic hypogonadism can develop secondary to steroid abuse, necessitating medical intervention.

The above side effects are not inclusive. For more detailed discussion of potential side effects, see the Steroid Side Effects section of this book.

Administration (Men):

Norclostebol acetate has been successfully used in clinical doses as low as 5-20 mg, which increased nitrogen retention for as long as 2 weeks.2 Effective doses for physique- or performance-enhancing purposes would fall in the range of 100-400 mg per week, taken for 612 weeks. Given the fast-acting nature of acetate injectables. the weekly dosage is generally subdivided into injections given at least every third day. An effective oral daily dosage falls in the range of 75100 mg, although would be less cost-effective and produce stronger negative changes in blood lipids than the injectable. Cycles (oral or injectable) would generally last 6-12 weeks. Use of norclostebol acetate will not effect rapid mass gains, but is likely to produce slow but steady increases in strength and lean muscle tissue, with a concurrent increase in fat loss and muscle definition.

Administration (Women):

Norclostebol acetate has been successfully used in clinical doses as low as 5-20 mg, which increased nitrogen retention for as long as 2 weeks. Effective doses for physique- or performance-enhancing purposes fall in the range of 50-75 mg per week for the injectable, or 25-50 mg daily for the oral, taken for no longer than 6 weeks. Note that virilizing side effects are still possible with use, and should be carefully monitored.

Availability:

Norclostebol acetate is no longer produced as a prescription agent.

1 Camerino B, Patelli B. et al. J Amer. Chem. Soc. 78 (1956):3540.

2 Anabolic Steroids and Sports Volume II. James E. Wright. Sports Science Consultants, Natick, MA 1982.