Most injectable anabolics have a bound ester that determines their half-life and duration: let's take a closer look at this.
This article is not intended to be a scientific treatise full of difficult words and incomprehensible phrases. Instead, we will try to explain in the most practical and understandable way possible what esters linked to various anabolic steroids are. Many people write to us asking about the difference between a propionate and an enanthate anabolic steroid, asking us what the differences are between the various esters and how to use them best.
What exactly is an ester?
Esters are organic compounds derived from a chemical reaction that we will not explain in detail to avoid boring you. Put simply, this reaction releases elements that have different absorption times in our bodies: by binding an ester to an anabolic molecule, we can therefore deduce that the half-life of the product can be manipulated. The anabolic half-life is simply the time that the product acts on our body.

Let's take a practical example
If a drug has a half-life of only two hours but the levels of that drug must be constant in the body, we have to take the drug every two hours. If a longer ester is attached to that drug, the half-life increases and we can "spread" the intake over time. Keep in mind that the half-life not only affects the duration of the drug's action in the metabolism but also affects the time it takes for the active ingredient to leave our body.
How many times have we asked ourselves: "Is testosterone enanthate or cypionate better?", "Is Sustanon (which is a mix of esters) or testosterone propionate better?" The answer is always the same... the molecule itself does not change, but the action times (and consequently the methods of administration) do. Based on your needs, you can choose the ester that suits you best.
Other effects that anabolic steroids have on our cycle.
It is universally accepted that a drug with a slower action has less pronounced side effects on the body. Anabolic steroids with a short half-life tend to cause peaks and troughs in blood concentration, which are not always beneficial for our metabolism.
Furthermore, anabolics with a fast ester tend to aromatize more due to the peaks and troughs in serum levels, meaning that the values are less stable. For the same reason, we recommend frequent (and possibly smaller) injections even with longer esters.
The most well-known anabolic esters:
It should be noted that there are hundreds of possible combinations of esters, and we are certainly not going to list them all here: here is a list of the most classic esters and those most commonly used in the world of anabolic steroids:
Acetate: The acetate ester is very short and enters the body very quickly. Trenbolone Acetate is a well-known product that uses this ester.
Propionate: a widely used and very fast ester with a half-life of just over 2-3 days. Well-known anabolics that use this ester are Testosterone Propionate and Masterone Propionate.
Phenylpropionate: with a half-life slightly longer than propionate, steroids with this stereotype should be injected about twice a week. Nandrolone NPP uses this ester.
Isocarpoate and Carpoate: These esters are very similar and have a half-life of about one week. They can be found in the mix of Sustanon.
Enanthate: A widely used ester with a half-life of between 10 and 14 days. The most famous is Testosterone Enanthate is based on this ester, as is Parabolan.
Cypionate: An ester practically identical to enanthate, created specifically to replicate the enanthate ester where it had been patented and was therefore unusable. Its half-life is very slightly longer. Testosterone Cypionate is part of this family of esters.
Decanoate: a fairly long ester (slightly over 14 days) made popular by its applications with nandrolone, which generated the Deca Durabolin.
Undercylinate: a very long ester that can increase the half-life to more than 21 days. Boldenone is the classic steroid that uses this ester.
