Steroid Half Life's

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

Thanks serb nice post this will help alot of people. And your dissapointing me with no pics or vids man. :crymeariver:

tonyk212000 said:

Thanks serb nice post this will help alot of people. And your dissapointing me with no pics or vids man. :crymeariver:

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i gave pics of me b4 the cycle.. i only started the cycle man.. patience, patience!!

I meant of the injections. But no rush you just excited me with the whole log.

tonyk212000 said:

I meant of the injections. But no rush you just excited me with the whole log.

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ill post my leg injections this monday.. pics probably though.

so with the halflife... does that mean with the drugs that only have a halflife of a matter of hours... they must be taken daily?

I dont intend on taking steroids... but would a longer half life mean a better working steroid?

Skeptic said:

so with the halflife... does that mean with the drugs that only have a halflife of a matter of hours... they must be taken daily?

I dont intend on taking steroids... but would a longer half life mean a better working steroid?

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http://www.muscletalk.co.uk/article-steroid-half-life.aspx

http://www.steroid.com/halflife.php

A good way to illustrate half-life is through the "flipping penny" experiment. I remember it well from my high school earth sciences class, and I'm sure many of you have probably done this exercise as well. This experiment involves placing 100 pennies inside a flat, closeable box. It is big enough that the pennies can sit side by side comfortably without overlapping each other. We begin with them all facing "heads-up". Next we close the box, give it a good shake, and then open it back up again. We then proceed to remove all pennies that are now "tails-up" in the box. This process is repeated until all of the pennies have been flipped and are removed from the box. We find that with each shake we loose about half of them. Around 50 the first flip, 25 the second, a dozen of so on the third, and so on. Although half of the original amount are tailed and removed on the first flip, it takes many successive tries to clear them all. And usually there are a couple of kids in the class that just can't seem to get the last few over without a lot of work. This illustrates well the way in which we measure drug metabolism in the body. Half-life is not an easy reference for the total time a drug will be found active in the body, but more a guide to optimizing a dosing schedule and avoiding unwanted peaks and troughs.

Unaided Steroid Half-Life

In the early years of steroid research, half-life was one of the biggest roadblocks to the development of commercial compounds. Natural steroid hormones have very short half-lives, which can make maintaining a normal blood level very difficult. For example, the half-life of free testosterone in the blood is only a few minutes (1), and from the site of injection it is well short of one hour. It is also so easily processed by the liver, that when you take it orally only a tiny fraction will actually be intact by the time it reaches the blood. With the oral route too difficult, repeated regular injections would probably be the only option to use testosterone for therapy at all. Obviously this is extremely tedious and uncomfortable to do, which led scientists to focus closely on ways to extend the life of this and other hormones in the body. Lets take a close look at the two most popular methods that were developed and ultimately adopted by the pharmaceutical industry for extending steroid half-life.

Oral 17alpha alkylation

You have most lively seen this reference in steroid materials. 17alpha alkylation is a process in which an extra carbon atom is added to the steroid molecule at the 17th position. This atom occupies a bond needed for the steroid to reduce to inactive 17-keto form, totally inhibiting this pathway of metabolism (2). The addition of 17 alkylation works to extend the half-life of the steroid considerably. With it we present we have half-lives measured in hours instead of only minutes. Unfortunately 17alpha alkylation also can lessen the ability of the steroid to bind to the androgen receptor. But the two traits balance out such that typically we still have a more physiologically active steroid molecule though (3). This alteration is the most favorable for oral dosing. Since the liver cannot process this type of steroid well, a large percentage will make it to the blood stream intact. It however is also somewhat toxic to the liver, and therefore less than ideal, especially if we are considering another avenue of administration such as injection.

Esterification for Injection

Most injectable steroid compounds utilize esters to increase their half-lives in the body. Esterification is a process where a carboxylic (fatty) acid is attached to the steroid molecule at the 17th beta position. One purpose of this is to protect its active 17-hydroxyl group. It is a prime target of steroid metabolism, and with the ester present this is prevented. The ester also makes the steroid compound more oil soluble. This makes it more difficult for the blood to pick it up and carry it into circulation, and likewise slows the rate the drug can leave the injection site. As a result, an inactive deposit of steroid can sit at the site of injection, releasing slowly for days or weeks into the blood stream. Once free in the blood the ester is removed quickly by enzymes, and the base steroid is rendered active.

We can look at the half-life of injectable compounds in two ways. The first is the half-life for the release of the steroid from the injection site. This is usually measured in days with most commercial steroid preparations. In fact the total active lifespan of most oil-based esterified injectables is measured in weeks, sometimes several weeks. The second measure is to look at its half-life in open blood circulation. This is more a figure for personal interest sake than any practical application however, as the only relevant measure to the user is its release half-life. In any event, we can look at a human injection study with nandrolone decanoate (Deca) and see some pretty accurate figures on both measures (4). First we find that Deca exhibits a mean half-life of 6 days for the release of steroid from the injection site. You can see why people say that Deca can technically be active for as long as a month after injection. Next we find a half-live of about 4 hours for the hydrolysis of serum nandrolone decanoate to free nandrolone, and the total distribution and metabolism of nandrolone. The half-life for simply the removal of the decanoate ester was about an hour or less. Provided in the chart below as well are the relative half-lives of nandrolone and two other esters of it from intramuscular injection depot (5).

Good read Serb. Good stuff to know if I start a cycle once.
Never will..but its good for those going too

thanks serb

So is a steroid with a shorter half life less harsh on the liver? But doesnt necesarily mean the gains are better?

very good information, this should be a sticky.

Skeptic said:

thanks serb

So is a steroid with a shorter half life less harsh on the liver? But doesnt necesarily mean the gains are better?

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I wouldn't say that necessarily... the orals pass through your liver twice where as injectables pass through once, making the orals (most having short half lifes) worse on your liver.

fair enough man, thanks for that