Primo vs. Mast

Masteron
pros: more aggressive (in a good way), much better libido, dry and hard look, more confidence and happy mood, crazy vascularity.

cons: harsh on your lipids, can make you look flat, crazy hair loss.

Primo
pros: makes you fuller, is a good AI, good for cutting to maintain lean mass, good fake natty look, RBC boost gives your skin a nice tan, chill steroid you won't feel much it just works in the background.

cons: actually lowers my libido even when e2 is in range & hair loss.

I much prefer Masteron over Primo. But hair loss man... not worth it.
I’ll also add Masteron, which negatively affects the prostate. For many, this becomes a problem.
 
Just re-reading this. Presumably another difference @Type-IIx, is that Masteron disrupts signalling at the oestrogen receptor whereas Primobolan doesn’t?
Yes, right. Primo may reduce serum estradiol, by acting as an AI and/or inhibiting 17β-HSD1. I can actually make a fairly strong case for the latter. It's worth real investigation.
 
My understanding is that Masteron negates E2 in two different ways. It has an effect similar to proviron, of occupying aromatise and preventing testosterone’s conversion. It also has a disruptive effect on genomic transcription at the E2 receptor.

Come to think of it I’ve not read any research to back this up. Could just be hearsay. I’m off to read the literature.
Masteron is not an Aromatase inhibitor nor is proviron. They don't act like Aromasin/Adex by blocking the conversion of Test to E - they directly antagonize estradiol. This is proven by bloodwork showing masteron not lowering serum e2. This does not mean masteron doesnt have anti estrogen effects, its just that the effects are different than primo.
 
For me..
mast
Pros- seems to protect me from gyno flairs up even with estrogen out of range. I have a better libido with mast. I’m more aggressive with mast. Little but if strength gain. Crazy erections. Shit is almost better than cialis for me.

Cons- doesn’t add fullness. Risk of looking flat.

Primo..
Pros- much fuller, better “look” than mast. . Doesn’t feel like I’m on anything really but seems to add more dense muscle than mast.
Lowers e2

Cons- expensive, not super great for my libido.. also lowers e2

All this is just my experience. Also, I’m bald so can’t speak on hairless. Gave up on that a long time ago.
 
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While I don't doubt that you've seen this, I have also seen it lower serum e2 which is one of the reasons it's used in prep

interesting. i want to add bayer did studies using mega dosages of proviron (500mg+) and no signs of e2 supression was found. not saying proviron does not have anti e effects just saying what the studies showed.
 
interesting. i want to add bayer did studies using mega dosages of proviron (500mg+) and no signs of e2 supression was found. not saying proviron does not have anti e effects just saying what the studies showed.
Proviron I don't have much knowledge on but that's really interesting
 
I'm betting with certain compounds (tren) that a flair up will still happen if e2 is out of range past a certain threshold.
So for me… my e2 can be low on tren and if I’m on tren long enough or high enough, I will start getting a flair up however, that’s not the case when I run mast with it
 
I wanna add mast to my next blast. I handle high test well but this last 4 month blast of 750 test shot up my hematocrit to much. It was easier to control on 500 test for sure. I'm leaning towards 500 test next blast ....how much mastron should I add? 400? I definitely don't want a weaker cycle than the 750 test one I did. So kinda the same cycle but with less test. I always throw in anavar too usually...that stuff always agrees with me.
 
I wanna add mast to my next blast. I handle high test well but this last 4 month blast of 750 test shot up my hematocrit to much. It was easier to control on 500 test for sure. I'm leaning towards 500 test next blast ....how much mastron should I add? 400? I definitely don't want a weaker cycle than the 750 test one I did. So kinda the same cycle but with less test. I always throw in anavar too usually...that stuff always agrees with me.
I’m generally 50-53 on 200 test. I ran 80mg telmisartan and it brought my hct down to low to mid 40s all while I was on a 6 month blast ramping up to 1g test and 1g primo. Had some tren sprinkled in there too. Maybe give thah a shot
 
I’m generally 50-53 on 200 test. I ran 80mg telmisartan and it brought my hct down to low to mid 40s all while I was on a 6 month blast ramping up to 1g test and 1g primo. Had some tren sprinkled in there too. Maybe give thah a shot
Yes that's another reason my hematocrit shot up I switched from telmisartan to losartan. I got some on the way.
 
there’s absolutely no point in using masteron unless it’s for contest prep or to dry out for a photo shoot. Primo can literally be used in off season, contest prep, TRT etc. doesn’t affect lipids whatsoever. Currently on 300 primo 300 test and 0 changes in lipids. I’ve seen Mast destroy lipids in matter of weeks on high doses.

I can’t comprehend how people put primo and mast in the same category and say they’re “interchangeable”. The only things that make them remotely similar are them being DHT derivatives and lowering E2.
Anyone willing to go 300 mg/wk Masteron only cycle over 300 mg/wk Primo only cycle? Not me.
On paper, primo is slightly more anabolic. In practice, primo is much more anabolic, and will build quality muscle over prolonged cycles, while Mast will keep you dry and flat, and give you some androgenic benefits.

Saw some folks compare Proviron to mast too. Proviron’s only goal is to free testosterone and lower SHBG or during Hrt protocol without AI. If you’re concerned about anything other than that, Proviron is not for you. There are better compounds for libido, mood, E2, pretty much everything.
I guess the other only advantage of it is it being an oral, if that’s an advantage to anyone on here.
 
there’s absolutely no point in using masteron unless it’s for contest prep or to dry out for a photo shoot. Primo can literally be used in off season, contest prep, TRT etc. doesn’t affect lipids whatsoever. Currently on 300 primo 300 test and 0 changes in lipids. I’ve seen Mast destroy lipids in matter of weeks on high doses.

I can’t comprehend how people put primo and mast in the same category and say they’re “interchangeable”. The only things that make them remotely similar are them being DHT derivatives and lowering E2.
Anyone willing to go 300 mg/wk Masteron only cycle over 300 mg/wk Primo only cycle? Not me.
On paper, primo is slightly more anabolic. In practice, primo is much more anabolic, and will build quality muscle over prolonged cycles, while Mast will keep you dry and flat, and give you some androgenic benefits.

Saw some folks compare Proviron to mast too. Proviron’s only goal is to free testosterone and lower SHBG or during Hrt protocol without AI. If you’re concerned about anything other than that, Proviron is not for you. There are better compounds for libido, mood, E2, pretty much everything.
I guess the other only advantage of it is it being an oral, if that’s an advantage to anyone on here.
Based off what experience are you suggesting this? Aren't you on your second cycle?

Also masteron doesn't lower e2. Lot of the stuff you are saying seems like it is regurgitated comments from bros on dated forums

.
 
Based off what experience are you suggesting this? Aren't you on your second cycle?

Also masteron doesn't lower e2. Lot of the stuff you are saying seems like it is regurgitated comments from bros on dated forums

.
So Mr Olympia understands every compound’s effect on human bodyjust because he’s tried it, following your logic?
I’m studying medicine and can understand pharmacology without testing everything under the sun on myself.
Drostanolone was literally made to treat breast cancer by changing E2-mediated gene transcription. What that means is while it may not directly lower E2, it does inhibit estrogen receptor binding affinity, which is what most people would care about on a cycle or from overall well-being perspective.
It’s literally FDA approved to be an antiestrogenuc drug. Don’t know what bro science you’re talking about.
 
So Mr Olympia understands every compound’s effect on human bodyjust because he’s tried it, following your logic?
I’m studying medicine and can understand pharmacology without testing everything under the sun on myself.
Drostanolone was literally made to treat breast cancer by changing E2-mediated gene transcription. What that means is while it may not directly lower E2, it does inhibit estrogen receptor binding affinity, which is what most people would care about on a cycle or from overall well-being perspective.
It’s literally FDA approved to be an antiestrogenuc drug. Don’t know what bro science you’re talking about.
Some of the most knowledgeable and educated people in the industry compare similarities and the interchangeability of the two
 
So Mr Olympia understands every compound’s effect on human bodyjust because he’s tried it, following your logic?
I’m studying medicine and can understand pharmacology without testing everything under the sun on myself.
Drostanolone was literally made to treat breast cancer by changing E2-mediated gene transcription. What that means is while it may not directly lower E2, it does inhibit estrogen receptor binding affinity, which is what most people would care about on a cycle or from overall well-being perspective.
It’s literally FDA approved to be an antiestrogenuc drug. Don’t know what bro science you’re talking about.
No, that is not my logic, but you cannot state it doesnt promote growth. There are no studies to state otherwise.

There are very limited studies on drostanolone to stating you are studying medicine is a little ridiculous.

Primo was utilized for anemia and I do not understand what your point of this argument is.

"I'm studying medicine so I know how drugs work"

They don't teach you AAS in school.

Give me a break
 
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"I'm studying medicine so I know how drugs work"

Give me a break
I was relating that to my point about Masteron and your presumably rhetorical question on what experience I’m basing it off.
One doesn’t need experience to understand how drugs work.
I have a lot to learn on this forum, specifically about diet and exercise and how to utilize high hormonal profile within short periods of time.
But just hearing someone say “hey guys mast/primo/whatever killed my libido therefore you should avoid it” is not something I would rely on while choosing a compound to run.
There’s a degree to which drugs affect individuals differently, but unless you’re an extreme outlier, most drugs will do what they’re supposed to.
So just because someone used some UGL fake/ underdosed product doesn’t mean the pharmacology is different had the product been legit and dosed/administered correctly.
So yes, medical knowledge could be important in extrapolating available data on pharmacokinetics. I’ve seen guys on here with decades of cycling under their belt recommend high test high deca cycles and then not understanding why their libido is dead.
What is less helpful is a typical gym bro comment like don’t teach me how to lift unless you bench 300 bro.
 
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