View Full Version : Primobolan~methenolone acetate

01-05-2010, 09:01 PM

(methenolone acetate)

Primobolan is one of those anabolic steroids which has a cult following not unlike the old original version of Masteron. Actually, as you can easily see from itīs anabolic:androgenic ratio below in the profile, itīs a pretty weak steroid but actually stronger(!) than Masteron in both regards. I donīt know anyone who has run both compounds at the same dose. We are probably justified in speculating that youīd probably get similar results from either of them, when you consider the fact that you are getting quite a bit less actual drug and more ester when you choose injectable Primobolan (which has the very long Enanthate ester attached to it) over Masteron (which has the very short propionate ester attached to it). In truth, I think part of the reason many Primobolan users have been disappointed is that they failed to use enough of it, for long enough. From itīs chemical structure and anabolic:androgenic rating, we can assume it is at least as effective as Masteron, on an equal Mg for mg basis. However, due to its ester (in the injectable version), it needs to be run for at least 12 weeks to see the full benefits from it. When you consider a measly dose of 400mgs of this stuff for 12 weeks will probably cost you around $500.

Itīs easy to see why many people have tried to use less...and have been disappointed with their results. On the other hand, many competitive bodybuilders consider Primobolan indespensible to their pre-contest drug routine, and wouldnīt consider dieting without it. Anyway...I think the comparison to Masteron (another great precontest drug) is the best one we can make, with reference to expected gains and results.

I happen to be one of the few people who have used Drostanolone Enanthate (Masteron with the Enanthate ester attached) as well as Methenolone Enanthate (injectable Primobolan). I can tell you that the results from these two compounds, when ester and mg potency are the same, are in fact very similar.

Effects of Primobolan

Letīs flesh out some of the various general effects of Primobolan, before we get into the differences between the oral and injectable versions... One study performed on sheep involved administering 100mgs of Methenolone, and electronically stimulating their lats (electronic stimulation was used because they kept falling off the chin-up bars). Anyway, when compared with the lat muscles of sheep who didnīt receive Methenolone, the receiving group gained significantly more muscle mass as well as strength (1)(2). Itīs also has a relatively high affinity for binding to the AR, actually binding better than testosterone (3). This ability to strongly bind to the AR may be why Primobolan is such a good "fat burner." Strong AR binding has been positively correlated with lypolysis (fat-burning) (8).

In addition, as this steroid can actually aid in reducing breast tumors, no ancillary products need be considered for use with Primobolan, and in fact, it may actually be a useful ancillary agent in itīs own right, similar to Masteron. Also, just like Masteron, Primobolan has no propensity to aromatize (convert to estrogen). Since it doesnīt aromatize, alot of the side effects commonly associated with estrogen will not be of concern. This means water retention, acne, and gyno will be non-existent more or less. this lack of water retention combined with the slow and steady gains provided by Primo may help to explain why it has earned a reputation for creating quality muscle gains. This also helps to explain why it is so expensive. Although estrogenic sides are not a concern, hair loss still, remains a very real concern with Primobolan, as with many DHT-Derived steroids. Many primobolan fans always include Finasteride and Ketoconazole (shampoo) in cycles containing Primobolan.

Although nobody would ever suggest to use Primobolan as a bulking agent, itīs been studied as an agent to halt wasting and possibly reverse many of the adverse effects of anemia. It is a shocking failure in both areas, according to some of the case studies Iīve read, (5)(6) and this should come to no surprise to anyone. Anadrol reigns supreme in this area, and nobody in the athletic community would ever compare those two drugs. However, Michael Mooney and many other respected doctors who work with AIDS patients have found sufficient evidence to claim that Primobolan is an immune enhancer and as such is very useful for AIDS patients (not that the FDA cares...Primobolan is still not approved for sale in the United States). AIDS patients arenīt really in need of Bulking Drugs, so an immune enhancer like Primo which will add small, quality gains in muscle is perfect for them. And since we arenīt even going to vaguely consider the use of Primobolan as a bulking agent, clearly this leaves us with considering it primarily for use in gaining and maintaining lean tissue. Itīs a great choice for this purpose, and many competitors have used it very successfully to retain muscle while on a calorie reduced diet. The reason Primo is so useful for this purpose is that one of its primary functions is to help your body retain nitrogen (7) at a greatly enhanced rate. The greater your nitrogen retention is, the more muscle you will build. In the case of using primo as a pre-contest drug, this nitrogen retention will help you retain muscle and ensure that your dieting preferentially favors fat loss over muscle loss.

Primobolan is a very unique steroid, as it is one of the few that comes in both an oral as well as an injectable version. I suppose Winstrol does also, but Primobolan actually has a different ester on the oral (acetate ) and injectable (Enanthate) versions. The oral version is one of the more interesting oral compounds Iīve looked into. For starters, itīs one of the few compounds available to athletes and bodybuilders which is both oral as well as non-17-alpha-alkylation. This alteration is (as Iīm sure you remember from other stuff Iīve written) what generally makes oral steroids survive their first pass through your liver, but also makes them Hepatoxic (Liver toxic). Well... oral Primo doesnīt have this feature, so it is very mild on your liver (actually it basically isnīt liver toxic at all), but also is largely destroyed by it, since 17 beta estrification and 1 alkylation is the method used to make this stuff orally available. Youīll need to take a lot of this stuff for it to be effective... 100mgs/day of the oral version is a safe estimate for reasonable gains& for women, you could get away with less; perhaps 25mgs/day. Even though the acetate ester has a 2-3 day active life, your liver will do some damage to oral primo, so every day dosing will still be necessary.

When men were given a 30-45mg dose of the oral version of Primo, they experienced a 15-65% decrease in gonadotropin levels (9). Remember, I said 100mgs is a good dose for gains... well, youīll also reduce your gonadotropin levels considerably. I have personally never understood why people recommend either oral or injectable Primobolan as a possible bridging compound for this reason... maybe at a too-low-to-do-anything dose of 10mgs it could be used as a bridge. And forget about using injectable Primo to bridge.

Hey... speaking about injectable Primo...

Iīve used this stuff at 200mgs/week and wasnīt very impressed with it. Generally, I think injectable primo needs to be used at a dose of at least 350mgs/week (100mgs/Every other Day), and preferably at a dose of 400-600mgs/week. I happen to like running it with testosterone propionate, but for convenience I would imagine most people would run it with Testosterone Enanthate, to keep dosing times the same (shooting it twice per week, in most cases).

Buying Primobolan

The unfortunate truth about injectable Primo is that itīs a very expensive chemical to obtain, and that price is reflected in the cost to the average consumer. Ten dollars per 1ml/100mg ampule is not unheard of, and Iīve seen it go for more. This is, of course, absurd. As if thatīs not enough, this is also the most commonly counterfeited steroids on the black market. I recommend buying Primobolan (either the oral or injectable) from a respected Underground lab instead of trying to play a game of "spot the fake steroid" in Mexico or Europe. The underground versions should cost between $5-7 for 100mgs of Methenolone and I wouldnīt really consider paying more for it, although I have seen the British Dragon version of this product priced up to $20/ml.

Primobolan Profile


(Oral Version is + Acetate Ester)
(Injectable Version is + Enanthate Ester)
Molecular weight of base: 302.4558
Molecular weight of Acetate ester: 60.0524
Molecular weight of Enanthate ester: 130.1864
Formula: C20H30O2
Melting Point:
Manufacturer: Schering
Effective dose(oral): (Men)50-100mgs/day; (Women) 10-25mgs/day
Effective dose (injectable): (Men) 350-600mgs/week; (Women) 100mgs/week
Active Life: 10-14 days (injectable); 4-6hrs (oral)
Detection Time: 4-5 weeks
Anabolic/Androgenic Ratio (Range): 88:44-57

Anabolic steroids (metenolone) improve muscle performance and hemodynamic characteristics in cardiomyoplasty. Ann Thorac Surg. 1995 Apr;59(4):961-9; discussion 969-70.
Effect of an anabolic steroid (Metenolon) on contractile performance of the chronically stimulated latissimus dorsi in sheep. Eur J Cardiothorac Surg. 1994;8(4):214-9.
Relative binding affinity of anabolic-androgenic steroids: comparison of the binding to the androgen receptors in skeletal muscle and in prostate, as well as to sex hormone-binding globulin. Endocrinology. 1984 Jun;114(6):2100-6.
[Anabolic therapy in metastatic breast cancer] Med Klin. 1981 Nov 20;76(24):689-91. German.
Partial remission and severe adverse effect caused by metenolone acetate in a male patient with aplastic anem. Eur J Haematol. 1995 Jul;55(1):57-8.
Fatal outcome of a patient with severe aplastic anemia after treatment with metenolone acetate. Ann Hematol. 1993 Jul;67(1):41-3.
Metabolic effects of anabolic steroids. Wien Med Wochenschr. 1993;143(14-15):368-75.
Biochim Biophys Acta. 1995 May 11;1244(1):117-20.
Comparative Studies about the influence of MetenoloneAcetate and Mesterolone on hypophysis and male gonads. Arzneimittelforshung. 1970 20(4) 545-7

01-05-2010, 09:05 PM
Effect of an anabolic steroid (Metenolon) on contractile performance of the chronically stimulated latissimus dorsi in sheep.

Fritzsche D (http://forums.rxmuscle.com/pubmed?term=%22Fritzsche%20D%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Krakor R (http://forums.rxmuscle.com/pubmed?term=%22Krakor%20R%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Asmussen G (http://forums.rxmuscle.com/pubmed?term=%22Asmussen%20G%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Lange S (http://forums.rxmuscle.com/pubmed?term=%22Lange%20S%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Kaufmann A (http://forums.rxmuscle.com/pubmed?term=%22Kaufmann%20A%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Zapf P (http://forums.rxmuscle.com/pubmed?term=%22Zapf%20P%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Mehlhorn G (http://forums.rxmuscle.com/pubmed?term=%22Mehlhorn%20G%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Berkei J (http://forums.rxmuscle.com/pubmed?term=%22Berkei%20J%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Widera R (http://forums.rxmuscle.com/pubmed?term=%22Widera%20R%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract).
Clinic for Heart Surgery, University of Leipzig, Germany.

In 12 sheep the left latissimus dorsi muscles (LD) were conditioned by chronic electrostimulation with a pulse generator (Itrel, Medtronic). Six animals (group B) received a weekly intramuscular injection of an anabolic steroid (Metenolon). After 14 weeks the contraction parameters of the left LDs (group A and B) and right LDs (control group) were investigated. The increase in weight of the conditioned LDs was 11.07% (+/- 1.06%) in group A and 79.97% (+/- 40.8; P < 0.05) in group B. The force capacity under stimulation patterns which were just tetanic was 1.15 kp in group A and 4.13 kp in group B (P < 0.05); under supramaximal stimulation patterns it was 4.23 kp (A) and 6.0 kp (B) (P = ns). The force time relation (dF/dt) was 6.7 kp/s for the left LDs in group A versus 16.4 kp/s for the right LDs (P < 0.01); in group B it was 5.13 kp/s for the left LDs versus 15.8 kp/s for the control muscles (P < 0.05). The maximal force (Fmax) per 100 g muscle weight did not differ significantly (A: 2.42 kp/100 g; B: 2.52 kp/100 g). In conclusion, the LD muscles which were subjected to both anabolic therapy and electrical stimulation showed a significant increase in their force capacity due to an enormous increase in mass. Fibre type transformation was complete only in group B. No fibre deterioration was observable in either group. No anabolic side effects were detected in the animals. With the use of anabolic steroids, therefore, a clearer direct increase in contractility on the left ventricle should be expected ("squeezing" theory), as well as a contribution to reduction in wall tension and myocardial oxygen consumption, respectively, according to Laplace's Law (via the considerable increase in thickness).

01-05-2010, 09:08 PM
Relative binding affinity of anabolic-androgenic steroids: comparison of the binding to the androgen receptors in skeletal muscle and in prostate, as well as to sex hormone-binding globulin.

Saartok T (http://forums.rxmuscle.com/pubmed?term=%22Saartok%20T%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Dahlberg E (http://forums.rxmuscle.com/pubmed?term=%22Dahlberg%20E%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract), Gustafsson JA (http://forums.rxmuscle.com/pubmed?term=%22Gustafsson%20JA%22%5BAuthor%5D&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsP anel.Pubmed_RVAbstract).

It is unclear whether anabolic steroids act on skeletal muscle via the androgen receptor (AR) in this tissue, or whether there is a separate anabolic receptor. When several anabolic steroids were tested as competitors for the binding of [3H]methyltrienolone (MT; 17 beta-hydroxy-17 alpha-methyl-4,9,11-estratrien-3-one) to the AR in rat and rabbit skeletal muscle and rat prostate, respectively, MT itself was the most efficient competitor. 1 alpha-Methyl-5 alpha-dihydrotestosterone (1 alpha-methyl-DHT; mesterolone) bound most avidly to sex hormone-binding globulin (SHBG) [relative binding affinity (RBA) about 4 times that of DHT]. Some anabolic-androgenic steroids bound strongly to the AR in skeletal muscle and prostate [ RBAs relative to that of MT: MT greater than 19-nortestosterone ( NorT ; nandrolone) greater than methenolone (17 beta-hydroxy-1-methyl-5 alpha-androst-1-en-3-one) greater than testosterone (T) greater than 1 alpha-methyl-DHT]. In other cases, AR binding was weak (RBA values less than 0.05): stanozolol (17 alpha-methyl-5 alpha- androstano [3,2-c]pyrazol-17 beta-ol), methanedienone (17 beta-hydroxy-17 alpha-methyl-1,4-androstadien-3-one), and fluoxymesterolone (9 alpha-fluoro-11 beta-hydroxy-17 alpha-methyl-T). Other compounds had RBAs too low to be determined (e.g. oxymetholone (17 beta-hydroxy-2-hydroxymethylene-17 alpha-methyl-5 alpha-androstan-3-one) and ethylestrenol (17 alpha-ethyl-4- estren -17 beta-ol). The competition pattern was similar in muscle and prostate, except for a higher RBA of DHT in the prostate. The low RBA of DHT in muscle was probably due to the previously reported rapid reduction of its 3-keto function to metabolites, which did not bind to the AR [5 alpha-androstane-3 alpha, 17 beta-diol and its 3 beta-isomer (3 alpha- and 3 beta-adiol, respectively)]. Some anabolic-androgenic steroids (only a few synthetic) bound to SHBG (1 alpha-methyl-DHT much greater than DHT greater than T greater than 3 beta-adiol greater than 3 alpha-adiol = 17 alpha-methyl-T greater than methenolone greater than methanedienone greater than stanozolol). The ratio of the RBA in rat muscle to that in the prostate (an estimate of the myotrophic potency of the compounds) was close to unity, varying only between about 0.4 and 1.7 in most cases.(ABSTRACT TRUNCATED AT 400 WORDS)

PMID: 6539197 [PubMed - indexed for MEDLINE]

01-08-2010, 03:03 PM
Women and Steroids. . . Primobolin Depot! Written by Leigh Penman Wednesday, 12 August 2009 14:13

PRIMOBOLAN DEPOT (Methenolone enanthate)


Primobolan Depot is the injectable version of the steroid methenolone and, although it produces a weaker effect than Deca-Durabolin, it's a very good muscle-building steroid that possesses predominantly anabolic attributes. The fact that an enanthate ester is added to this steroid enables a slow and gradual release from the injection site. This allows for a longer half-life of approx 14 days (similar to other enanthate esters); yet most athletes prefer to administer it on a weekly basis.

Primobolan's popularity seems to stem from the fact that it's the only steroid that works well on a low calorie diet (making it a pre-contest drug of choice) and side effects are rarely a problem since it's relatively non toxic, it's low in androgens, and it doesn't convert to estrogen (aromatize); therefore, estrogenic side effects are not an issue. Additionally, Primo seems to have a positive effect on the immune system (explaining its use in AIDS patients). When you consider all these facts it's hard to believe that Primobolan Depot is not legally approved by the FDA in the United States...but that's politics for you!

Having said all of the above, it should be noted that Primobolan does have some side effects including light acne, deepening voice and increased hair growth. These sides seem to result from the small androgenic component coupled with a very long half life in the system. Remember, the greater the exposure to a compound, the more likely you are to experience side effects. However, it displays low liver toxicity and usually has little effect on blood pressure and cholesterol, which makes it one of the safest injectable anabolic steroids available. It's also worth pointing out that, in men, the body's endogenous testosterone production is only negatively affected when high dosages are taken for prolonged periods of time.

Female athletes can get good results from 50 -100mg a week and, if desired, it can be stacked with 25mg of Winstrol Depot every other day (although virilization problems may occur in sensitive individuals). A safer option would probably be stacking Primo with 10mg Anavar (or Winstrol oral, 10mg) per day, which represents a cautious dose for those seeking to experiment with anabolics.

All in all, when you consider the fact that Primobolan is effective on a low calorie diet, builds lean mass, adds hardness and tone AND positively effects the immune system, it's easy to see why it is one of the most popular steroids on the market and has gained something of a ‘cult' following over the years.


After asking the Rx Muscle forum women their thoughts on Primobolan, the general consensus is that it's a good drug in terms of quality gains. In terms of side-effects, they can vary from individual to individual with the most common being oily skin, frequent break-outs, loss of hair and lowering of the voice. Hair loss seems to be the major issue with this drug which can be alleviated to some degree with the use of Nizoral shampoo- which prevents DHT build up on the scalp.

Favored dosages range from 50mg/week to 100mg/week with one user reporting great results with 200mg/week for a 7-8 week period (having started at 100mg/week).

Going back to the issue of side effects. it's worth pointing out that Primo is a highly counterfeited drug and care must be taken to ensure that you really are using Primo. It has been reported that some unscrupulous companies substitute Testosterone Propionate for Primobolan in their products. So buyers beware!


"Methenolone is a DHT based steroid with mild anabolic and androgenic properties prescribed mostly to women and children in its oral form. It does not form estrogens when it interacts with the aromatize enzyme, which makes it a great choice for women looking to minimize excess estrogen production. Primo is generally the first choice for any female athlete new to injectable drugs; however my personal experiences with Primo were far from favorable.

"I'm sensitive to precursors of dihydrotestosterone (DHT) in general, and Primo usually makes my hair fall out in strands at dosages as low as 50mg/week. That being said, I did not experience any other residual androgenic effects typical of Primo usage...such as oily skin, acne, increased facial/body hair growth etc. Generally speaking though, Primo is considered safe for most women, with problems usually being dose related.

"Gains on Primo are generally solid and gradual with the drug being an excellent choice while on a cutting diet. Most women I have worked with respond well to a dosage of 50-100mg per week for a period of 14-16 weeks with little or no adverse effects."

So there you have it, the lowdown on Primobolan which, along with Anavar, is definitely the most popular drug used by female bodybuilders. Watch this space for our profile on Winstrol- a steroid often used by women as part of a stack or as a substitute for Anavar which can often be highly priced.

http://www.rxmuscle.com/articles/bios-a-interviews/614-women-and-steroids-primobolin-depot.html (http://www.rxmuscle.com/articles/bios-a-interviews/614-women-and-steroids-primobolin-depot.html)

09-28-2011, 02:36 AM
Is 300mg sufficient enough for lean muscle gain in a 23yr male? would there really need to be testosterone run with primobolan since its a DHT...(im referring to erections sake)

was thinking a low dose of sustanon 250 with 300mg of primo for 10 weeks


10-05-2011, 05:26 AM
Is 300mg sufficient enough for lean muscle gain in a 23yr male? would there really need to be testosterone run with primobolan since its a DHT...(im referring to erections sake)

was thinking a low dose of sustanon 250 with 300mg of primo for 10 weeks


I have run 400mg and 600mg a wk before on different cycles and got no problems with it.

side effects of steroids (http://side-effects-steroids.com)

10-22-2011, 05:45 PM
You never know till you try. Don't be afraid to experiment. Funny how people will experiment with much more hazardous compounds like recreational drugs and alcohol but when it comes to steroids everyone is so damned afraid. If there is a drug you can afford to experiment with, its steroids.

I'm 2 weeks out from a show and I cut out my test prop last week and have since been running tren, winny (injectable), and halo and my sex drive is still going strong. Although that might be the yohimbine I'm using :P

10-22-2011, 05:47 PM
I will say the one downside I could definitely see is that if you're not running test and you get shut down and you're not running any aromatizing compounds, your estro might be get very low which could have a negative impact on your hdl and ldl levels.

12-03-2012, 10:02 PM
Love this one, can be use all year long

07-16-2015, 04:29 PM
hard to tell but seems the more negative sides come from the ladies who use the injectable form as the longer ester makes them experience the androgen sides on a more steady basis, can the same be said for the Oral as its mostly destroyed in the liver, is 50 mg a day considered easily tolorated? im sure its try it and find out but my GF who is a long time anavar fan want to try a two compond stack and oral primo seems to be the best choice compared to winny / anavar. can anyone speak to the sides / doses based on Oral injestion

02-06-2016, 12:27 AM
Duchaine made denise rukowski a BEAST back in the day with 1/4 of an Anadrol daily.. supposedly..