Testosterone Enanthate
Testosterone ester, injectable. Half-life 7.2 days.
Also called Test E, Testoviron
Serum concentration from a single dose
single 100 mg dose over 5.1 weeks, vertical lines mark each half-life elapsed since the peak
What the numbers mean
The serum curve carries a 7.2 day terminal half-life, longer than the 4.5 days often quoted for the ester itself, because what the blood sees is depot release rather than ester hydrolysis. About 72% of each milligram is testosterone once the ester weight is removed.
The active fraction is the share of each milligram the model treats as reaching circulation as active compound. For an injectable that is ester weight: a milligram of enanthate is not a milligram of testosterone. For an oral it is bioavailability, the share that survives the gut and the liver, which is why some orals sit far below 100%. How the model works.
Where these numbers come from
The half-life and the peak concentration are both read from a published reference. Read it on PubMed Central.
Common questions about Testosterone Enanthate
What is the half-life of Testosterone Enanthate?
The model uses a terminal half-life of 7.2 days for Testosterone Enanthate. For an injectable that figure is the rate the oil depot releases the compound rather than the rate the body clears it, which is why it runs longer than the half-life of the ester itself.
How long does Testosterone Enanthate take to reach steady state?
Roughly 5.1 weeks, on a schedule that does not change. Steady state is conventionally taken as five half-lives, the point at which each dose is clearing about as fast as the next one arrives, and at a half-life of 7.2 days that puts Testosterone Enanthate at 5.1 weeks of climbing before the curve flattens.
How long does Testosterone Enanthate stay in your system?
About 5.6 weeks after the last dose for the serum level to fall to a few percent of where it was, on the same five-and-a-half half-life reasoning. That is the modelled blood level only. It is not a detection window: metabolites are found by testing long after the parent compound has gone, and this model says nothing about that.
Put Testosterone Enanthate on a timeline with the rest of your cycle and watch the curves add up.
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