Nandrolone Phenylpropionate (NPP)
19-nor ester, injectable. Half-life 2.4 days.
Also called NPP, Durabolin
Serum concentration from a single dose
single 100 mg dose over 12 days, vertical lines mark each half-life elapsed since the peak
What the numbers mean
The short nandrolone ester at 2.4 days, which is what separates it from Deca on a chart. Reaches steady state in under two weeks rather than two months, and anchors the calibration for the nandrolone family.
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.
Same base compound
Common questions about Nandrolone Phenylpropionate (NPP)
What is the half-life of Nandrolone Phenylpropionate (NPP)?
The model uses a terminal half-life of 2.4 days for Nandrolone Phenylpropionate (NPP). 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 Phenylpropionate (NPP) take to reach steady state?
Roughly 12 days, 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 2.4 days that puts Nandrolone Phenylpropionate (NPP) at 12 days of climbing before the curve flattens.
How long does Nandrolone Phenylpropionate (NPP) stay in your system?
About 13.2 days 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 Phenylpropionate (NPP) on a timeline with the rest of your cycle and watch the curves add up.
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