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Daz69

True Half-life Tables

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There has been much heated debate on half-lives of esterified testosterones over the years, here are some fairly accurate tables:

 

The formula used for calculating the rate of compound release at a given day t is:

λ * N(t)

Where λ is the decay constant equal to ln(2)/h, h being the half life of the compound given in days; and N(t) is the half-life equation given by:

N(t) = n * e^(-t/λ)

Where n is the original dose of the compound in mg and t is given in days.

Terminal Half-lives

  • Testosterone Propionate: 0.8 days
  • Testosterone Phenylpropionate: 1.5 days
  • Testosterone Isocaproate: 4.0 days
  • Testosterone Enanthate: 4.5 days
  • Testosterone Cypionate: 5.0 days
  • Testosterone Decanoate: 7.5 days
  • Testosterone Undecanoate: 20.9 days
  • Trenbolone Acetate: 1.0 days
  • Trenbolone Enanthate: 4.5 days
  • Masteron Propionate: 0.8 days
  • Masteron Enanthate: 4.5 days
  • Nandrolone Phenylpropionate: 1.5 days
  • Nandrolone Decanoate: 7.5 days
  • Boldenone undecylenate : 14.0 days
  • Primobolan Oral: 5 hours
  • Primobolan Injectable: 4.5 days
  • Halotestin: 7 hours
  • Anadrol: 14 hours
  • Dianabol: 5 hours
  • Turinabol: 16 hours
  • Winstrol Oral: 8 hours
  • Winstrol Injectable: 1.0 days
  • Anavar: 10 hours
  • Superdrol: 10 hours

These half-lives are approximations, and may vary slightly depending on injection site, carrier oil, and other factors.

Note: A different list of half-lives is often copy and pasted on various sites, claiming that, for example, the half-life for the propionate ester is 4.5 days and that the half-life for the enanthate ester is 10.5 days. This list is incorrect, and is the result of flawed calculations by Bill Roberts many years ago. See the "References" section for more information.

Active Dose

Injectable steroids are typically bound by esters, which comprise a portion of the steroid's weight. Because of this, 100mg of, for example, testosterone enanthate does not equate to 100mg of pure testosterone. In this case, there is only 70mg of testosterone being injected, and the remaining 30mg is the enanthate ester. This is taken into account when plotting cycles on this site, as different esters have different weights. Listed below is the percentages of the actual hormones for different steroid and ester combinations:

  • Testosterone Propionate: 80%
  • Testosterone Phenylpropionate: 66%
  • Testosterone Isocaproate: 72%
  • Testosterone Enanthate: 70%
  • Testosterone Cypionate: 69%
  • Testosterone Decanoate: 62%
  • Testosterone Undecanoate: 61%
  • Trenbolone Acetate: 87%
  • Trenbolone Enanthate: 70%
  • Masteron Propionate: 80%
  • Masteron Enanthate: 70%
  • Nandrolone Phenylpropionate: 67%
  • Nandrolone Decanoate: 64%
  • Boldenone undecylenate: 61%  [Edit to keep Tom happy]
  • Primobolan Oral: 100%
  • Primobolan Injectable: 70%
  • Halotestin: 100%
  • Anadrol: 100%
  • Dianabol: 100%
  • Turinabol: 100%
  • Winstrol Oral: 100%
  • Anavar: 100%
  • Superdrol: 100%

References

Behre HM, Nieschlag E. 1998 Comparative pharmacokinetics of testosterone esters. In: Nieschlag E, Behre HM, eds. Testosterone: Action, Deficiency, Substitution, ed 2. Berlin: Springer-Verlag; 329–348.

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2 hours ago, Slinwarrior said:

That must be why eq sux,  a gram and I'm only actually getting 610mgs

 

 

Equipoise? I'm confused.. whoever wrote this must mean undecylnate? Equipoise is boldenone and it's also common in acetate and cypionate esters... why does it say equipoise? What does "equipoise" mean? 

 

Also this % doesn't really mean anything other than exactly that. Each compound and ester has its merits. If it was all just about the highest amount g for g everyone would just use TNE and orals. Which is why saying something sucks because you are only getting 61% of what you are taking is a dumb way to look at it. But it is an excuse to use even more eh? 

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Also what is the difference in stanozolol  depot and oral Stan? It's exactly the same thing!!! There is no difference the only difference is how it is administered either IM or orally. The things you are adding to the powder to change it into the white liquid we all know do nothing to the active ingredient whatsoever.

 

if turning it into a suspension changes that then why doesn't mixing it with fillers and binders to press tablets do the same thing? Injectable winny is just micronised stanozolol powder suspended in either water or oil. It's the same thing. And with the injectable it has been proven you are getting more nitrogen retention so it's actually better.

 

I'm sorry but this information is not credible.

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5 hours ago, Realtalk said:

 

 

Equipoise? I'm confused.. whoever wrote this must mean undecylnate? Equipoise is boldenone and it's also common in acetate and cypionate esters... why does it say equipoise? What does "equipoise" mean? 

 

 

Its from Equus, latin for horse, as it was originally designed for horses..

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5 hours ago, Realtalk said:

Also what is the difference in stanozolol  depot and oral Stan? It's exactly the same thing!!! There is no difference the only difference is how it is administered either IM or orally. The things you are adding to the powder to change it into the white liquid we all know do nothing to the active ingredient whatsoever.

 

if turning it into a suspension changes that then why doesn't mixing it with fillers and binders to press tablets do the same thing? Injectable winny is just micronised stanozolol powder suspended in either water or oil. It's the same thing. And with the injectable it has been proven you are getting more nitrogen retention so it's actually better.

 

I'm sorry but this information is not credible.

 

As far as I'm aware there should be no difference as there was no ester attached to either the oral or injectable form of stanozolol.. I've since known a more recent oil based injectable with short ester made by Apex in the UK..

I'm unsure as to why there is a supposed molecular difference between the original oral and injectable stanozolol, as there shouldn't be one... it looks close to an acetate ester..

On the whole its an accurate guide..

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8 hours ago, Daz69 said:

 

Its from Equus, latin for horse, as it was originally designed for horses..

 

I know what it means. I was asking what it means in regards to this post. Equipoise is just a brand name a drug company gave to their product. Equipoise isn't an ester. For something supposedly written by scientists it's pretty sloppy. 

 

Hey slin warrior, it's usually best to know what you're using before you take it bro. Not find out what you're actually taking when you read it on an Internet forum. Aren't you using like 4000mg of gear all up a week and you don't know how it all works lol ffs.

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2 hours ago, Realtalk said:

 

I know what it means. I was asking what it means in regards to this post. Equipoise is just a brand name a drug company gave to their product. Equipoise isn't an ester. For something supposedly written by scientists it's pretty sloppy. 

 

Hey slin warrior, it's usually best to know what you're using before you take it bro. Not find out what you're actually taking when you read it on an Internet forum. Aren't you using like 4000mg of gear all up a week and you don't know how it all works lol ffs.

 

I've edited it Tom... Hope you are happy... I want you to be happy Tom.. :-)

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Just now, Realtalk said:

 

 

Its not accurate information is all I'm saying bro.

 

It's probably as accurate as your going to get, given differences in individual human physiology for half life values...

 

I've posted in another thread more precise data on ester molecular weight, written by Peter Van Mol aka Big Cat a well known biochemist.. As molecular weight should be precise, if its out by the smallest of margins then it can't be the molecule its meant to be..

 

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Molecular weight can actually vary depending on the isotopes or ratio of isotopes present as constituents of the molecule.  A well known and somewhat extreme example would be heavy water which contains deuterium atoms rather than the more commonly occurring lighter form of hydrogen giving it both a molar mass and density of about 111% that of ordinary protium containing water.

 

 

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9 hours ago, PETN said:

Molecular weight can actually vary depending on the isotopes or ratio of isotopes present as constituents of the molecule.  A well known and somewhat extreme example would be heavy water which contains deuterium atoms rather than the more commonly occurring lighter form of hydrogen giving it both a molar mass and density of about 111% that of ordinary protium containing water.

 

 

 

I am aware isotopes contain extra neutrons therefore extra molecular weight.. I was speaking only in the context of steroids and their accompanying esters..

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14 hours ago, LuckyD said:

Would this have any effect on the steroid detection times for people being tested ? 

 

Would what have effect..?

Clearance times would, but half life is only a part, remember active metabolites can stay in the system much longer than the actual parent hormone..

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