steroid compounds , their half lives and activity levels

**Simon1972** · 04-04-2015, 03:49 PM

below is a breakdown of the most commonly available compounds, their half lives and activity percentages. Pretty rudimentary stuff, but alas missing from most knowledge databases.

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
Equipoise : 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 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.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%
Equipoise: 61%
Primobolan Oral: 100%
Primobolan Injectable: 70%
Halotestin: 100%
Anadrol: 100%
Dianabol: 100%
Turinabol: 100%
Winstrol Oral: 100%
Winstrol Injectable: 87%
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.

**NACH3** · 04-04-2015, 03:56 PM

Awesome Simon... Well done! I'm going to copy this for referencing(dosing etc)!

**Simon1972** · 04-05-2015, 12:20 AM

Should be a stickie! But I'm sure it'll disappear like all the other high value posts

**Mr.BB** · 04-05-2015, 04:36 AM

Sticky plz

**lovbyts** · 04-05-2015, 05:14 AM

Add it to the lab section please.

Good info

**The Deadlifting Dog** · 04-05-2015, 07:47 AM

Please note that this list is of terminal half-lives and not a list of half-lives.

Terminal half-lives are a function of half-lives.

**zempey** · 04-05-2015, 07:52 AM

That is some good info, thanks. Now on that note, should one take 30% more test e to get the full 200mg? Same with deca , at only 64% that low dose becomes a very low dose.

**kelkel** · 04-05-2015, 10:55 AM

Originally Posted by zempey

That is some good info, thanks. Now on that note, should one take 30% more test e to get the full 200mg? Same with deca, at only 64% that low dose becomes a very low dose.

No. It's always worked before with your normal dosing schedule. No need to micromanage numbers.

**bsh** · 04-05-2015, 11:33 AM

This is wonderful info! Thx...

**Lee_1978** · 04-05-2015, 02:09 PM

Originally Posted by Simon1972

below is a breakdown of the most commonly available compounds, their half lives and activity percentages. Pretty rudimentary stuff, but alas missing from most knowledge databases.

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
Equipoise : 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 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.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%
Equipoise: 61%
Primobolan Oral: 100%
Primobolan Injectable: 70%
Halotestin: 100%
Anadrol: 100%
Dianabol: 100%
Turinabol: 100%
Winstrol Oral: 100%
Winstrol Injectable: 87%
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.

Get for reference!

**Lee_1978** · 04-05-2015, 02:14 PM

How do terminal half lives differ from standard half lives? I'm a bit baffled?

**Simon1972** · 04-05-2015, 04:14 PM

Originally Posted by Lee_1978

How do terminal half lives differ from standard half lives? I'm a bit baffled?

The way I understand it terminal is the time it tasks for the drug to eliminate from your system. Standard half life is the time you end up with half of the actual drug in your system.the graph above I think explains in more detail. Maybe kel can confirm this?

**kelkel** · 04-05-2015, 08:52 PM

Correct. Explains it well Simon. Nice postings!

**AR's King Silabolin** · 08-07-2015, 01:01 AM

Originally Posted by Simon1972

The way I understand it terminal is the time it tasks for the drug to eliminate from your system. Standard half life is the time you end up with half of the actual drug in your system.the graph above I think explains in more detail. Maybe kel can confirm this?

Wrong. Standard half-life is the time you end up With half of the drug in your system. That is correct. But terminal halflife is the time the drug needs to for decreasing 50% after pseudo-equilibrium of distribution has been reached. Wtf is pseudo-equilibrium? Dont ask me, Guess you have to study chemistry to fully understand. Didnt get that from my native Language either. But i Guess then the terminal half-life may be Shorter, like 5 days, than the halflife, 8 days, for test e.
My conclusion would be that we have to look at the half-life, not the terminal half-life, when we do drugs. Because i Guess the drug also hits us before it reaches its "equilibrium". But its just an educated Guess from 30 mins of Research:-)

Maybe pseudo-equilibrium is when the drug is evenly distributed in the blood. And i Guess that will take some time.