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Is Proviron Really An AI?

Some people claim there is no scientific evidence that Proviron is actually an AI. They say that this incorrect conclusion was arrived at by assuming Proviron (essentially a methylated DHT), would funtion the same as pure DHT–that is, as an AI.

Is there any studies providing evidence that Proviron either is, or is not, an AI?



A little search turned up this…

Proviron has four distinct uses in the world of bodybuilding. The first being the result of its structure. It is 5-alpha reduced and not capable of forming estrogen, yet it nonetheless has a much higher affinity for the aromatase enzyme (which converts testosterone to estrogen) than testosterone does. That means in administering it with testosterone or another aromatizable compound, it prevents estrogen build-up because it binds to the aromatase enzyme very strongly, thereby preventing these steroids from interacting with it and forming estrogen. So Mesterolone use has the extreme benefit of reducing estrogenic side-effects and water retention noted with other steroids, and as such still help to provide mostly lean gains. Its also been suggested that it may actually downgrade the actual estrogen receptor making it doubly effective at reducing circulating estrogen levels.

The second use is in enhancing the potency of testosterone. Testosterone in the body at normal physiological levels is mostly inactive. As much as 97 or 98 percent of testosterone in that amount is bound to sex hormone binding globulin (SHBG) and albumin, two proteins. In such a form testosterone is mostly inactive. But as with the aromatase enzyme, DHT has a higher affinity for these proteins than testosterone does, so when administered simultaneously the mesterolone will attach to the SHBG and albumin, leaving larger amounts of free testosterone to mediate anabolic activities such as protein synthesis. Another way in which it helps to increase gains. Its also another part of the equation that makes it ineffective on its own, as binding to these proteins too, would render it a non-issue at the androgen receptor.

Thirdly, mesterolone is added in pre-contest phases to increase a distinct hardness and muscle density. Probably due to its reduction in circulating estrogen, perhaps due to the downregulating of the estrogen receptor in muscle tissue, it decreases the total water build-up of the body giving its user a much leaner look, and a visual effect of possessing “harder” muscles with more cuts and striations. Proviron is often used as a last-minute secret by a lot of bodybuilders and both actors and models have used it time and again to deliver top shape day in day out, when needed. Like the other methylated DHT compound, drostanolone, mesterolone is particularly potent in achieving this feat.

Lastly Proviron is used during a cycle of certain hormones such as nandrolone, with a distinct lack of androgenic nature, or perhaps 5-alpha reduced hormones that don’t have the same affinities as DHT does. Such compounds, thinking of trenbolone, nandrolone and such in particular, have been known to decrease libido. Limiting the athlete to perform sexually being the logical result. DHT plays a key role in this process and is therefore administered in conjunction with such steroids to ease or relieve this annoying side-effect. Proviron is also commonly prescribed by doctors to people with low levels of testosterone, or patients with chronic impotence. Its not perceived as a powerful anabolic, but it gets the job done equally well if not better than other anabolic steroids making it a favorite in medical practices due to its lower chance of abuse.

The first paragraph states that it is an aromatase inhibitor…

Proviron can ‘tie up’ some of the aromatase enzyme which can reduce estrogen aromatization somewhat. This is adequate if used in conjunction with a steroid such as boldenone however if used in conjunction with testosterone, depending on the dose, it may not be enough to prevent estrogenic effects.

Thanks for the replies, guys. It was mainly just an interesting theoretical question. I personally love Proviron, but I would never count on it as an effective AI in a stack including heavily aromatizable AAS.

I do find it amazingly effective, for example, in keeping any sexual side effects from Tren in check. I use it with all cycles containing Test due to its ability to bind to SHBG.

Does proviron help with mood at all. For example if running test, tren or test, npp?

i’m interested in this, as I’m running test and NPP right now and have noticed a “little” mood swing here and there.

I don’t know if you could say Proviron directly helps mood, but by keeping sexual sides at bay, for example, it certainly helps indirectly.

I just used Tren for the first time in my last cycle (~400 mg. EW). I love the stuff. I feel absolutely great on it, and experience no significant mood alterations–no irritability, etc. I was using 40 mg. Proviron ED.

Now, my lack of negative sides from the Tren could be due to the fact that the dosage I was using was rather moderate. However, from everything I have read about Tren or other’s use of it, I should have experienced some sexual sides. Not only did this not happen, but my sex drive remained very high throughout. I do think this was due to my use of Proviron.