Provibol introduction, history and overview
Provibol is the trade / trade name for the androgen known as Mesterolone. It is an oral product and is not considered an anabolic steroid. This is because its anabolic activity is known to be extremely weak – so weak, in fact, that it can be practically considered non-existent. Provibol was first developed by Schering in 1934, making it one of the oldest steroids produced and marketed for medical use. Mesterolone is so old, in fact, that it shared its inception with Methyltestosterone in 1935 and Testosterone propionate in 1937, which were two of the first anabolic steroids put into use in medicine. Of course, Methyltestosterone and Testosterone Propionate are remembered for all their glory while Proviron is / was less well known. This is likely due to the fact that the former two anabolic steroids have been shown to be very strong anabolic agents, while the second is not.
Although Provibol is considered a very old drug, it remains the test of time as known as a compound that has impressive efficacy as a drug alongside an impressive history of safety and tolerance among patients. Within the medical establishment, Provibol was used as a drug to treat the decline in well-being in elderly males due to the decline in androgen levels, libido dysfunction in males and infertility.
Its use as a fertility aid is where Provibol has really been emphasized in the medical literature. This is because while nearly all anabolic / androgenic steroids are known to cause temporary infertility, Proviron in normal therapeutic doses actually barely suppresses endogenous gonadotropins (LH and FSH) when used. However, Proviron is poorly misunderstood as a compound that increases LH, which it does not. Instead, research has shown that Provibol provides the androgenic effects needed for spermatogenesis in specific areas in the testes.
Schering still produces Mesterolone under the name Provibol all over the world today. It has also been sold under several brands, including Pluriviron (in Germany by Asche), Vistimon (in Germany by Jenepharm) and Restore (in India, by Brown and Burke). What is interesting, however, is that Provibol has never been approved for use on the prescription market in the United States.
Provibol chemical characteristics
Provibol is a modified derivative of dihydrotestosterone (DHT) through the addition of a methyl group on its first carbon (1-methyl dihydrotestosterone). As previously mentioned, it is an extremely weak anabolic, which is why Proviron is almost always referred to as an androgen (or androgenic steroid). Studies have shown the reason for its weak anabolic effects: it shares a similar property with its parent compound (DHT) – it is rapidly metabolized and broken down into inactive metabolites once it enters muscle tissue.
This has always been the problem with dihydrotestosterone itself – once it enters muscle tissue, the 3-hydroxysteroid dehydrogenase enzyme (where it is in very high concentration in muscle tissue) binds to it and renders it inactive by converting it into a compound that has no anabolic effect. This is the real reason for Provibol's weak anabolic effects. There have been false rumors about Proviron's weak anabolic nature circulating among bodybuilding communities that Provibol "blocks the androgen receptor in muscle tissue," which is wrong, and this rumor should therefore be silenced.
An added benefit of Proviron is its ability to have a high affinity for SHBG (Sex Hormone Binding Globulin), which is a protein that binds to anabolic steroids in the blood (i.e., Testosterone) and renders them completely inactive once related. The use of Provibol in this case together with other anabolic steroids can amplify the activity and effects of other anabolic steroids through this path, leaving more free and unbound testosterone to do its job.
A well-known advantage of Provibol is also its ability to act as an anti-estrogen through its activity as an aromatase inhibitor. It should be noted, however, that its activity as an aromatase inhibitor is not considered as strong as Aromasin, Arimidex or Letrozole, but it still works and can be used as such. Its strength as an aromatase inhibitor can be compared to Arimidex, but slightly lower in terms of strength.
Provibol side effects
Since Provibol is a DHT derivative, it carries no risk for estrogenic side effects. In fact, as mentioned above, Provibol acts as an anti-estrogen through its activity as an aromatase inhibitor in the body. This may result in the mitigation of estrogenic side effects from other compounds through the reduction of total circulating plasma levels of estrogen. Research has shown that due to this effect of Proviron, it has been used medically in the treatment of gynecomastia and breast cancers due to its strong androgenic nature combined with its anti-estrogenic abilities.
Since Proviron is primarily an androgen, it carries with it the risk of androgenic side effects, and they are more pronounced with higher dosages. Provibol's androgenic side effects include: an increase in oily skin (due to increased sebum production / secretion), increased hair and hair growth, and increased risk of triggering MPB (Male Pattern Baldness) in those who are genetically sensitive or predisposed to it. Women are also subject to virilization through the use of Proviron, which is the development of male characteristics in women (ie deepening of the voice, growth of facial hair, enlargement of the clitoris, etc.). It is also important to note that since Proviron is already a DHT derivative, products such as Finasteride, Proscar or Dutasteride will do absolutely nothing to reduce Proviron's potential androgenic effects.
Since Proviron is not alpha C-17 alpha (it is methylated on its first carbon instead), research has shown that it is not known to produce hepatotoxic effects, and liver problems are extremely unlikely with this compound.
However, Provibol side effects include negative effects on the cardiovascular system. Studies have shown that 100 mg of Proviron per day for 6 months showed very significant negative effects on cholesterol values, both by increasing bad cholesterol (LDL) and decreasing good cholesterol (HDL) by 65% and 35% respectively.
It is also likely that Provibol may have a suppressive effect on the endogenous production of natural testosterone (although this is considered very weak). However, studies have shown that 150 mg or less per day of Proviron that no significant suppression of testosterone results. In the same studies, higher dosages (300 mg or more per day) caused significant suppression of testosterone levels.