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Half-Life's of just about everything

biohazard1971

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I got this from British Bodybuilding and thought it may be useful in this beginners forum:

Steroid Half life's - anyone new to steroids may be wondering what this means, even some steroid users may also be wondering what this means. So here in simple terms you can read and hopefully understand all about steroid half life's and what this term means.
Basically every drug has a half life, steroids included. If for example, you were to inject 200mg of Decadurabolin once weekly, for 6 weeks, how would you know when you were "off"? Would you be "off" when you had finished your last dose? You would be able to calculate this from the half life of Deca. The half life of Deca is around 14 days. This means that 14 days from your last shot of 200mg of Deca, your blood levels of Deca will contain 100mg of the steroid. Another 14 days from then, i.e. 28 days from last dose, your blood levels will contain 50mg of the steroid. This amount then keeps halving every 14 days. Therefore you can clearly see that when you finish your cycle, even though you are not putting any steroids into your body, you may think that you are now "off", however you still have, and will still have for some time after your last dose, "active" blood levels of the steroid. Therefore you can plan what to use, how long for, and how long off your cycle, based on these half life's.

Below a list of half-life's of the most commonly used steroids, esters and ancillary compounds.

Oral steroids Drug Active half-life
Anadrol / Anapolan50 (oxymetholone) 8 to 9 hours
Anavar (oxandrolone) 9 hours
Dianabol (methandrostenolone, methandienone) 4.5 to 6 hours
Methyltestosterone 4 days
Winstrol (stanozolol)
(tablets or depot taken orally) 9 hours

Depot steroids Drug Active half-life
Deca-durabolin (Nandrolone decanate) 14 days
Equipoise 14 days
Finaject (trenbolone acetate) 3 days
Primobolan (methenolone enanthate) 10.5 days
Sustanon or Omnadren 15 to 18 days
Testosterone Cypionate 12 days
Testosterone Enanthate 10.5 days
Testosterone Propionate 4.5 days
Testosterone Suspension 1 day
Winstrol (stanozolol) 1 day

Steroid esters Drug Active half-life
Formate 1.5 days
Acetate 3 days
Propionate 2 days
Phenylpropionate 4.5 days
Butyrate 6 days
Valerate 7.5 days
Hexanoate 9 days
Caproate 9 days
Isocaproate 9 days
Heptanoate 10.5 days
Enanthate 10.5 days
Octanoate 12 days
Cypionate 12 days
Nonanoate 13.5 days
Decanoate 15 days
Undecanoate 16.5 days

Ancillaries Drug Active half-life
Arimidex 3 days
Clenbuterol 1.5 days
Clomid 5 days
Cytadren 6 hours
Ephedrine 6 hours
T3 10 hours
 
Very nice reference man! Appreciate it. I don't see the Trens on there. Should I just assume that they would follow the half-lifes of the esters, so Tren E = ~10.5 days?
 
Thank you

Very interesting and helpful. Also makes me think common protocols dose too frequently.

For example if the half life of cyp is 10 days, why is it twice weekly or sometimes eod?
 
Why dose it say test P has a half life of 4.5 days yet the "prop ESTER" has a life of 2 days...? There are a couple things that look off in that read.
 
Hey bro good find I must say...I am wondering why though the half life of test prop would be 4.5 days when the half life of the prop ester is two days? could anybody help me out there
 
Very interesting and helpful. Also makes me think common protocols dose too frequently.

For example if the half life of cyp is 10 days, why is it twice weekly or sometimes eod?

Right. So, it test cyp is 12 days I'm still trying to understand why people are adamant that by pinning 2x/wk keep blood levels incrementally more level than just 1x/wk.

Using EQ as an example, with a half life of 14 days to make it easy, I built a time series wedge based on a once/wk, 12 week cycle: Basically it shows by Wk 12 (which is your theoretical peak), you have 689.06mg of EQ in your blood. There are no up/downs throughout until you hit wk 13 when you experience the biggest drop from 689 to 492.

Blood Level Totals
Wk 1 200.00
Wk 2 350.00
Wk 3 450.00
Wk 4 525.00
Wk 5 575.00
Wk 6 612.50
Wk 7 637.50
Wk 8 656.25
Wk 9 668.75
Wk 10 678.13
Wk 11 684.38
Wk 12 689.06
Wk 13 492.19
Wk 14 344.53
Wk 15 246.09
Wk 16 172.27
Wk 17 123.05
Wk 18 86.13
Wk 19 61.52
Wk 20 43.07
Wk 21 30.76
Wk 22 21.53
Wk 23 15.38
Wk 24 10.74

So, can so one please explain the science behind people pinning longer esters such as cyp and enth multiple times a week?
 
Depot vs Ester

Here is a link that explains the difference between the actual depot steroid, and the steroid ester, It'd be far too long to copy and paste here, but it has some very good information that should answer all of your questions:
Steroid Half Life

I also did a google search of "difference between depot steroids and steroid esters" and found a wealth of information.
 
Here is a link that explains the difference between the actual depot steroid, and the steroid ester, It'd be far too long to copy and paste here, but it has some very good information that should answer all of your questions:
Steroid Half Life

I also did a google search of "difference between depot steroids and steroid esters" and found a wealth of information.

Thanks for the link. The full article is a really good read. I read through it and according to this source there is absolutely no reason to pin more than 1x week if using a longer ester (enth, cyp, etc.). This seems so against the grain of what I read across the boards. Anyone else care to chime in here?
 
Thanks for the link. The full article is a really good read. I read through it and according to this source there is absolutely no reason to pin more than 1x week if using a longer ester (enth, cyp, etc.). This seems so against the grain of what I read across the boards. Anyone else care to chime in here?

i'm wondering myself too...


also, whats going on with the acetate and prop? Shouldn't acetate be 2 days and prop be 3 days...---It's the opposite though...

phenylprop---4.5 days...
and so on and so on ...
 
Most of these half life charts are mere copy and paste jobs of some list which originally appeared 15-20 years ago. I don't believe this chart is accurate at all. In fact, I'd half these purported half lives and that is much more accurate.
The simplest and best advice I've ever heard on half life calculation is take the number of carbons in the ester and multiple that by a value of .7 this gives you a relative half life value per 24 hour per period.
To illustrate in greater depth. Take Acetate. 2 carbons x.7 = 1.4 days would be its half life under this model. This is reason for the ED recommendations. Its also why IMO Ace is not advisable EOD. Propionate 3 carbons x.7 = 2.1 days This is the reason behind the EOD recommendation and why some like myself prefer to shot prop's ED even. Enanthate 7 carbons x.7 = 4.9 days This would be the reason behind the E3D or twice a week recommendations. Because most of us believe and realize you want to inject with enough frequency that you are not hitting your compounds half life so as to minimize the swings in saturation levels. I mean shoot I know people hitting enanthates daily but to each their own.
All of us who have spent years in the gear game can probably testify that our real world experience is much closer to this .7 carbon factor that all this steriod half life lists which is you notice are all mere copy and paste jobs of each other.
 
Most of these half life charts are mere copy and paste jobs of some list which originally appeared 15-20 years ago. I don't believe this chart is accurate at all. In fact, I'd half these purported half lives and that is much more accurate.
The simplest and best advice I've ever heard on half life calculation is take the number of carbons in the ester and multiple that by a value of .7 this gives you a relative half life value per 24 hour per period.
To illustrate in greater depth. Take Acetate. 2 carbons x.7 = 1.4 days would be its half life under this model. This is reason for the ED recommendations. Its also why IMO Ace is not advisable EOD. Propionate 3 carbons x.7 = 2.1 days This is the reason behind the EOD recommendation and why some like myself prefer to shot prop's ED even. Enanthate 7 carbons x.7 = 4.9 days This would be the reason behind the E3D or twice a week recommendations. Because most of us believe and realize you want to inject with enough frequency that you are not hitting your compounds half life so as to minimize the swings in saturation levels. I mean shoot I know people hitting enanthates daily but to each their own.
All of us who have spent years in the gear game can probably testify that our real world experience is much closer to this .7 carbon factor that all this steriod half life lists which is you notice are all mere copy and paste jobs of each other.

good info here ...

never thought of it like that ...
 
If we are going to copy & paste we need to make sure info is correct & dosent contradict itself(multiple time).
 
Last edited:
Most of these half life charts are mere copy and paste jobs of some list which originally appeared 15-20 years ago. I don't believe this chart is accurate at all. In fact, I'd half these purported half lives and that is much more accurate.
The simplest and best advice I've ever heard on half life calculation is take the number of carbons in the ester and multiple that by a value of .7 this gives you a relative half life value per 24 hour per period.
To illustrate in greater depth. Take Acetate. 2 carbons x.7 = 1.4 days would be its half life under this model. This is reason for the ED recommendations. Its also why IMO Ace is not advisable EOD. Propionate 3 carbons x.7 = 2.1 days This is the reason behind the EOD recommendation and why some like myself prefer to shot prop's ED even. Enanthate 7 carbons x.7 = 4.9 days This would be the reason behind the E3D or twice a week recommendations. Because most of us believe and realize you want to inject with enough frequency that you are not hitting your compounds half life so as to minimize the swings in saturation levels. I mean shoot I know people hitting enanthates daily but to each their own.
All of us who have spent years in the gear game can probably testify that our real world experience is much closer to this .7 carbon factor that all this steriod half life lists which is you notice are all mere copy and paste jobs of each other.

I dug up this study back from '85 and is relevant to this topic. It shows a half-life of just 6 days for Nandrolone decanoate. So your method is much more accurate than that other list. See below:

________________________________________________________________

Acta Endocrinol Suppl (Copenh) 1985;271:19-30 Related Articles, Links


Pharmacokinetic parameters of nandrolone (19-nortestosterone) after intramuscular administration of nandrolone decanoate (Deca-Durabolin) to healthy volunteers.

Wijnand HP, Bosch AM, Donker CW.

Nandrolone decanoate (Deca-Durabolin) was injected intramuscularly into healthy volunteers. One group of females received one injection of 100 mg and three groups of males received one injection of 200 mg, two repeat injections of 100 mg or four repeat injections of 50 mg respectively. The serum levels of nandrolone (19-nortestosterone) were determined by radioimmunoassay and used to estimate pharmacokinetic parameters. The following pharmacokinetic parameters were found: a mean half-life of 6 days for the release of the ester from the muscular injection depot into the general circulation; a mean half-life of 4.3 h for the combined processes of hydrolysis of nandrolone decanoate and of distribution and elimination of nandrolone; a mean nandrolone serum clearance of 1.55 1 X h-1 X kg-1. The half-life of hydrolysis of nandrolone decanoate in serum was of the order of one hour or less. The data are consistent with linear kinetics.
 
And just to add something most charts leave out is the ester weight penalty or deduction which is necessary.
According to the erroneous copy and paste chart enanthate has a half life of 10.5 days. Let's just have some fun with numbers then. Assume you took a hit of 500mg of enanthate. Well if you didnt know any better you'd then figure you'd have 250mg of test left after 10.5 days and 125mg left after 21 days and what about 62.5mg left after 31.5 days right?
Now let's look at it using the carbons x.7 factor and deducting for ester weight. The enanthate ester weighs about 28% of your test value. That is only 72% of your test is really test. So that 500mg shoot is really 360mg. Now lets follow enanthate half life assuming 7 carbons x.7 =4.9 lets just call it 5 for simple math's sake. So after just 5 days [not 10.5] we'd have not 250 but 180mg of actual test left and after 10 days not 125 but 90mg. 90mg versus 250mg depending on the methodology you buy into after 10 days. Continuing this train after 15 days we'd hit an actual test value of 45mg.
What is the common advice for use with a SERM PCT if using longer esters like enanthate? 2 weeks after your last pin? Under this model you can see make that makes more sense.
Now admittedly, we are using the example of a 1 500mg and clearly anyone who has been on for 8-12 weeks will have a greater cumulative value. But in principle the point remains the same.

Hopefully, the above information sheds more light into J_Diggs questions
 
I dug up this study back from '85 and is relevant to this topic. It shows a half-life of just 6 days for Nandrolone decanoate. So your method is much more accurate than that other list.

Yeah like anything there is a degree of variance involved when trying to assert an all knowing overarching formula for accuracy. But the carbons x.7 really is the best thing out there. For instance, decanoate has 10 carbons x .7 = 7 day half life. Well the document you reference says 6 days, so my formula must be off right?... Well 6 days versus 7 days is a lot less difference than 15 days as we find in most of the copy and paste jobs out there. Besides who's to say those guys weren't off by a day too :p. But seriously, if you plan your calculations for compound selection, injection frequency and coming off time for PCT using this methodology it really is your best option IMO
 
Agreed. So I also dug this up, and it's a robust enough topic that it could probably stand alone in a separate thread, but does anyone have any experience with 'front-loading' while using longer esters?

Please read this article and tell me what you think. It's quite logical.

AAS: Front-loading steroid cycles | For Bodybuilders
 
On a side note, I've contributed a bunch of posts today, yet my post count keeps going backwards? WTF. I was at 86 or 87 and after that last one down to 80? Are heads deleting posts/threads left & right or what? At this rate it'll be years before I hit a few hundred posts, haha.
 
Agreed. So I also dug this up, and it's a robust enough topic that it could probably stand alone in a separate thread, but does anyone have any experience with 'front-loading' while using longer esters?

Please read this article and tell me what you think. It's quite logical.

AAS: Front-loading steroid cycles | For Bodybuilders

Yes I'm a believer in and user of front loading techniques, especially with longer chained esters. Tren Ace is about the only thing I wont front load because quite frankly a double dose of tren ace is a lot to handle. But I will double up on props. Im a blast and cruiser myself but even in my case I like to frontload when Im re-blasting.
At this point in my gear career I pretty much will cruise on 200mg/wk of test and 200mg/wk of mast. When it comes time to blast depending on what Im doing both dose wise and compound wise I usually hit my weekly dose in the first day of the [re]blast. So if I intend to use 500mg of test a week on Day 1 or whatever you wanna call it 500mg of test goes in. It really just accelerates getting you body to the levels you desire to be at sooner. From there depending on my injection frequency I adjust dose to maintain desired levels
 
Right. So, it test cyp is 12 days I'm still trying to understand why people are adamant that by pinning 2x/wk keep blood levels incrementally more level than just 1x/wk.

Using EQ as an example, with a half life of 14 days to make it easy, I built a time series wedge based on a once/wk, 12 week cycle: Basically it shows by Wk 12 (which is your theoretical peak), you have 689.06mg of EQ in your blood. There are no up/downs throughout until you hit wk 13 when you experience the biggest drop from 689 to 492.

Blood Level Totals
Wk 1 200.00
Wk 2 350.00
Wk 3 450.00
Wk 4 525.00
Wk 5 575.00
Wk 6 612.50
Wk 7 637.50
Wk 8 656.25
Wk 9 668.75
Wk 10 678.13
Wk 11 684.38
Wk 12 689.06
Wk 13 492.19
Wk 14 344.53
Wk 15 246.09
Wk 16 172.27
Wk 17 123.05
Wk 18 86.13
Wk 19 61.52
Wk 20 43.07
Wk 21 30.76
Wk 22 21.53
Wk 23 15.38
Wk 24 10.74

So, can so one please explain the science behind people pinning longer esters such as cyp and enth multiple times a week?

I pin twice a week cuz i am on 500 test e and 400 eq a week and i cannot fit all that in 1 syringe so i break it up every 3 days
 

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