Consequences of Anabolic Androgenic Steroids – Part 1

By Dr. Craig Perlman, Board Certified Endocrinologist

There has been much controversy recently pertaining to testosterone replacement therapy (TRT) amongst mixed martial arts fighters.  Previous studies have demonstrated a prevalence rate of abuse of anabolic steroids in high school athletes as high as 6%.  With a significant number of athletes initiating anabolic androgenic steroid intake at such a young age, it can be assumed that the prevalence of anabolic steroid abuse on an individual basis is often chronic in nature.  In light of this chronicity of abuse, there is a concern for the development of long-term consequences. However, these consequences are both long-term and short-term.  Also, the risk of adverse effects is proportional to the dosage and frequency administered.  This article will be the first in a series of articles that will discuss various side effects that may occur as a result of anabolic androgenic steroids.

Testosterone is one form of pharmacologic therapy in a broad class of medications known as anabolic androgenic steroids.  Testosterone may be administered via transdermal (topical gel or patch), oral (pill), or intramuscular (injection). Testosterone elicits both anabolic and androgenic effects.  Anabolic effects pertain to the increase in muscle mass and strength, while androgenic effects pertain to the development of acne, male pattern baldness and voice deepening.

Testosterone has a relative androgenic: anabolic activity of 1:1.  Anabolic steroids such as Oxandrolone (Anavar), Nandrolone (Deca-Durabolin), and Stanozolol (Winstrol) were developed to elicit the anabolic effects with less androgenic effects.  When a fighter receives a therapeutic exemption for TRT, they are receiving testosterone, usually in the form of testosterone enanthate or testosterone cypionate injections.

gynecomastia2Male breast enlargement, or gynecomastia, may occur as result of testosterone administration. Testosterone is converted to estrogen by a ubiquitous enzyme known as aromatase, which results in feminizing characteristics, including breast enlargement and change in voice pitch.  An aromatase inhibitor, such as anastrozole or an anti-estrogen such as tamoxifen is given concomitantly with testosterone to counteract this deleterious effect.  Theoretically, there will be an increased risk of breast cancer with more breast tissue present.  Also, these medications that are utilized to prevent gynecomastia have additional side effects including blood clots, osteoporosis, and abnormal cholesterol levels (low HDL i.e. good cholesterol).  Nandrolone (Deca-Durabolin) is notorious for causing gynecomastia.

Testosterone is normally converted to either estrogen or dihydrotestosterone (DHT).  Dihydrotestosterone and its analogues thereof, are responsible for causing the androgenic effects (male pattern baldness, acne) of testosterone and anabolic steroids.  Nandrolone causes conversion to dihydronandrolone, a modified version of DHT, which is less androgenic than DHT. A result of this however, is that there is less DHT to suppress aromatization to estrogen, resulting in gynecomastia.  Anti-estrogens and aromatase inhibitors have been shown to be modestly effective in recent onset gynecomastia and show minimal resolution of long-standing gynecomastia.  Thus, surgical correction is often necessary.

Stay tuned for future articles pertaining to other adverse and beneficial effects of testosterone.


This is the second article in a series of articles pertaining to performance enhancing drugs (PEDs) and MMA.  The first article can be found here

Dr. Craig Douglas Perlman MD practices in Internal Medicine and Endocrinology, Diabetes & Metabolism.