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Proviron

Oral, non-17aa. Half-life 12.5 hours.

Also called Mesterolone

12.5 hours
Half-life
3%
Active fraction
Oral
Route
2.6 days
Approaches steady state

Serum concentration from a single dose

Modelled serum concentration curve for a single 100 mg dose of Proviron

single 100 mg dose over 2.6 days, vertical lines mark each half-life elapsed since the peak

What the numbers mean

A 12.5 hour half-life. The striking figure here is bioavailability: the manufacturer data puts it near 3%, so the plotted concentration sits far below what the milligram number alone would suggest.

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 Bayer product information.

Common questions about Proviron

What is the half-life of Proviron?

The model uses a terminal half-life of 12.5 hours for Proviron. 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 Proviron take to reach steady state?

Roughly 2.6 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 12.5 hours that puts Proviron at 2.6 days of climbing before the curve flattens.

How long does Proviron stay in your system?

About 2.9 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 Proviron on a timeline with the rest of your cycle and watch the curves add up.

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