Aromasin Side Effects
Throughout this profile, it is clearly stated that the use of aromasin (or aromatase inhibitors) should be aimed at controlling estrogen, not eliminating it.
The reduction of estrogen in the body can cause negative changes and problems in the body, especially if estrogen is suppressed for a long period of time using an aromatase inhibitor.
Aromasin side effects are generally manageable, and mostly manifest very differently in men than in women, as we have previously demonstrated in this profile that aromasin affects women more than men due to their different endocrine physiology.
This is true for all aromatase inhibitors, and in general, the decrease in serum estrogen levels in women is much greater than in men, often resulting in greater fat deposition.
Side effects associated with decreased estrogen
Almost all aromasin side effects are a result of the decrease in total circulating estrogen levels in the body due to the inhibition of the aromatase enzyme.
Below are the main potential aromasin side effects associated with decreased estrogen.
Joint and bone pain: Estrogen is actually an important hormone for promoting and maintaining bone mineral content, which promotes bone strength.
That's why postmenopausal women are more likely to develop osteoporosis because estrogen levels naturally decline with age.
Therefore, a decrease in bone strength over time is a hallmark of all aromatase inhibitors, which all act to lower total serum estrogen levels.
However, aromasin in particular has been proven to actually strengthen bones and prevent fractures in the short term, while Arimidex and Letrozole have been shown to severely reduce bone strength in the same study [1].
At the same time, long-term use in breast cancer patients has been shown to decrease bone strength over time.
While short-term use may not be a problem for bone strength and may even be beneficial, many male users report increased bone and joint pain when estrogen levels drop well below normal physiologic levels due to Aromasin use.
This bone and joint pain invariably subsides once the user stops taking Aromasin or adjusts the Aromasin dosage to allow estrogen levels to return to normal physiological levels.
Fatigue: Similar to the problem of bone and joint pain in anabolic steroid users who lower their estrogen levels too much, persistent fatigue is also a common reported Aromasin side effect.
This is due to the aforementioned lowered estrogen levels.
Estrogen is well known to play an important role in the proper functioning of the central nervous system (CNS), and when estrogen is reduced below normal physiological levels through aromatase inhibitors, it can lead to chronic fatigue, a symptom that can only be properly treated by restoring circulating estrogen levels to normal.
Negative effects on cholesterol: This is a side effect common to all aromatase inhibitors, or any substance that reduces total circulating estrogen levels in the body.
Aromasin side effects are no exception.
As discussed earlier in this profile, aromasin has been shown to negatively affect cholesterol levels in most studies to a much lesser degree than all other aromatase inhibitors, but this side effect is nonetheless present with aromasin.
The fact that aromasin has a lesser impact on blood lipid profiles may be a sufficient reason to use aromasin over other aromatase inhibitors.
However, these side effects are also the reason for the emphasis on controlling estrogen levels rather than eliminating them completely, and it is important to understand how this mechanism works.
Estrogen is known to play a very important role in the liver, where it works to produce good cholesterol levels (increasing HDL, the good cholesterol, and decreasing LDL, the bad cholesterol).
When estrogen levels decrease below normal physiologic levels, cholesterol changes occur, resulting in a decrease in good cholesterol (HDL) and an increase in bad cholesterol (LDL), which increases the risk of cardiovascular disease (CVD).
In one study, testosterone enanthate 300 mg per week for 20 weeks without the use of an aromatase inhibitor resulted in a 13% reduction in HDL cholesterol, and when the testosterone dose was increased to 600 mg per week, the reduction in HDL cholesterol was further increased to 21% [2].
Thus, the data examined shows a very clear increase in estrogen via aromatization and hepatic metabolism, which actually helps to offset the negative cholesterol changes caused by supraphysiological amounts of anabolic steroid use.
This is not surprising considering that estrogen itself is known to have a positive effect on cholesterol levels.
Therefore, the use of aromatase inhibitors and their impact on the cholesterol profile should always be kept in mind by any user considering the addition of an aromatase inhibitor during a cycle or for PCT.
It is recommended to use the lowest dose of an aromatase inhibitor during a cycle with the goal of controlling estrogen rather than eliminating total estrogen levels.
The idea in this case is to keep estrogen levels within the normal range so that aromatization does not cause them to spike, while at the same time preventing them from dropping to near zero due to the use of a full dose of aromatase inhibitor.
Androgenic Side Effects
Because Aromasin is a steroidal aromatase inhibitor, which the other two major aromatase inhibitors are not, it exhibits androgenic activity in the body as evidenced by various studies and anecdotal reports from anabolic steroid users.
This can also be a beneficial effect for those who wish to use aromasin during PCT, when aggression and drive are at their lowest.
Two studies have shown that while Arimidex and Letrozole have no androgenic, progestogenic, or estrogenic effects (weight gain, acne, hirsutism, etc.), aromasin exhibits mild androgenic properties and can cause steroid-like side effects such as slight weight gain and acne at high doses.[3] [4]
These effects are typically seen at aromasin doses of 25 mg or more.
In addition, 17-hydroxymesterone, a metabolite of aromasin, is an even more potent androgen and serves to further enhance the androgenic effects of aromasin[5].
It is important to understand that the androgenic effects of aromasin are very minimal at best, but may be mild (such as small pimples) in individuals who are highly sensitive to androgenic side effects.
In general, androgenic effects from aromasin side effects are not a problem.
Androgenic side effects include increased sebum secretion (oily skin), increased acne breakouts (associated with increased sebum secretion), increased body and facial hair growth, and an increased risk of developing benign prostatic hyperplasia (BPH) and male pattern baldness (MPB) (in people who have the genetic traits necessary to develop these conditions).
Medical references
[1] Effects of the steroid aromatase inhibitor exemestane and the nonsteroidal aromatase inhibitor letrozole on bone and lipid metabolism in ovariectomized rats. Paul E. Goss1, Shangli Qi, Angela M. Cheung, Haiqing Hu, Maria Mendez, Kenneth P. H. Pritzker. September 1, 2004; 10; 5717.
[2] Testosterone dose-response relationship in healthy young men. Bhasin S, Woodhouse L. et al. Am J Physiol Endocrinol Metab 281:E1172-81, 2001
[3] Minimum effective exemestane dose for endocrine activity in advanced breast cancer. Bazetta E., Zillembo N., Norberasco C., Martineti A., Mariani L., Ferrari L., Buzoni R., Greco M., Bartoli C., Spagnoli I., Danesi G. M., Artale S., Paolini J. Eur. J. Cancer, 33: 587-591, 1997.
[4] Risks and benefits of aromatase inhibitors in postmenopausal breast cancer. Michaud L. B., Buzdar A. U. Drug Saf., 21: 297-309, 1999.
[5] The 17-hydroxylated metabolite of exemestane exerts biological effects as an androgen. Eric A. Ariazi, Andrei Leitão, Tudor I. Oprea, Bin Chen, Theresa Lewis, Anne Marie Bertucci, Catherine G.N. Sharma, Sean D. Gill, Helen R. Kim, Heather A. Schiff, Jennifer R. Pyle, Alexis Madrack, Ann L. Donato, Dong Cheng, James R. Page, and V. Craig Jordan. Mol Cancer Ther 2007 Nov 6; 2817
