Nandrolone Decanoate (Deca)
19-nor ester, injectable. Half-life 10.2 days.
Also called Deca, Deca-Durabolin
Serum concentration from a single dose
single 100 mg dose over 7.3 weeks, vertical lines mark each half-life elapsed since the peak
What the numbers mean
A 10.2 day half-life means levels keep climbing for roughly seven weeks before the curve levels off. The long tail is the reason it is plotted well past the last injection.
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 Oxford Academic.
Same base compound
Common questions about Nandrolone Decanoate (Deca)
What is the half-life of Nandrolone Decanoate (Deca)?
The model uses a terminal half-life of 10.2 days for Nandrolone Decanoate (Deca). 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 Nandrolone Decanoate (Deca) take to reach steady state?
Roughly 7.3 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 10.2 days that puts Nandrolone Decanoate (Deca) at 7.3 weeks of climbing before the curve flattens.
How long does Nandrolone Decanoate (Deca) stay in your system?
About 8 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 Nandrolone Decanoate (Deca) on a timeline with the rest of your cycle and watch the curves add up.
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