Anabol 4-19 (chemical name norclostebol acetate) is a derivative of the nandrolone compound, which is most often associated with deca durabolin. However, the decanoate ester attached to deca durabolin is very long, and it has a half-life of 14 days. Meanwhile, anabol 4-19 has a very short acetate ester attached to it, whose half life is just 3 days. This means you can recover much quicker after cycle, as the ester will clear out of your system three times faster than in the case of deca durabolin.


Fig 1. Norclostebol chemical structure

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Anabol 4-19 was created in the 1950's, but today it does not exist anymore. However, if there was a re-birth of shorter cycles and active steroid juicers were to move away from blast and cruise type of attitudes, then this would be a compound that could make a comeback.

Background and facts

On paper, anabol 4-19 is five times more potent than testosterone in terms of its anabolic traits, and has about a quarter of the androgenic traits.

Interestingly, unlike deca durabolin, anabol 4-19 does not aromatize, which means it does not have estrogenic side effects.

Use in animals

Anabol 4-19 was obtained from the European black market in the 1990's for use in animal breeding. Animals (bovine such as cattle or buffalo) were given the compound and then urine analysis were taken over a 3 week span. This was illegally done at the time.

We know that today finaplex is given to bovine before slaughter in order to add mass, but people do not realize that it was precisely anabol 4-19 that may have helped open the door to this controversial farming tactic.

Side effects

Norclostebol acetate does not aromatize, and such estrogenic side effects as gynecomastia, water retention, bloating, insomnia and high blood pressure do not occur. However, we must remember that it is still a fast acting anabolic steroid, and it should be respected. If you abuse the compound you can get the typical side effects, such as lipid strain and aggressiveness, so a good support supplement is recommended during the cycle. N2Guard is one of the best supplements for the role of being a support supplement and organ cleanser.

Furthermore, just like with all anabolic steroids, a post cycle therapy (PCT) should be implemented after finishing the cycle, as anabol 4-19 is suppressive and it will affect the HPTA (hypothalamic-pituitary-testicular axis) function.

User results

I was able to contact a few older bodybuilders who have used this compound to get an idea about the type of results and experiences they had. What I found is that the results were very unique, and based on what we know about the compound, we can clearly see why. You can expect masteron like effects, but more androgenic results. In addition, primobolan like effects, but much faster acting due to the shorter half life. In fact, anabol can be compared very closely to anavar, with the major difference being that it comes in injectable form, and has more androgenic effects.

Half life

In its injectable form, anabol 4-19 has the acetate ester attached to it, so it has a half life of approximately 3 days. Nevertheless, it is important to understand that half life is not the same thing as detectable time, or how long the compound will be active in the system.

Half life means that, in this particular case, after 3 days only half of what you took will be leftover. Once you have established a dosing protocol into cycle, the approximate time that a compound will be active in the body is 3-4 half lifes. Hence, with the acetate ester it would take approximately 12 days, or about 2 weeks, to clear the system to low amounts leftover.


With the acetate ester, it is a good idea to pin every other day. Dosages of anabol 4-19 can range from 200 milligrams (mgs) up to 600mgs per week in men, with the exact dosages depending on the athlete's experience. Moreover, it was popularly stacked with different compounds, most notably testosterone.

Female dosages would have been much lower, similar to these of deca - probably around 50mgs a week, but there were better options, as anabol 4-19 does have some androgenic traits.

Due to the short half life it is not necessary to run a long cycle with norclostebol acetate, and you can easily get away with 6-8 week runs.

Finally, keep in mind that anabol 4-19 does not require an aromatase inhibitor (AI) only if ran alone, and you would still need an AI if you stacked this steroid with other aromatizing compounds.


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