Testosterone is a steroid hormone from the androgen group. Testosterone is primarily secreted in the testes of males and the ovaries of females although small amounts are secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid. In both males and females, it plays key roles in health and well-being. Examples include enhanced libido, energy, immune function, and protection against osteoporosis. On average, the adult male body produces about twenty times the amount of testosterone an adult female's body does.

Testosterone Cypionate is a single-ester, long-acting form of testosterone. Due to the length of its ester (8 carbons) it is stored mostly in the adipose tissue upon intra-musuclar injection, and then slowly but very steadily released over a certain period of time. A peak is noted after 24-48 hours of injection and then a slow decline, reaching a steady point after 12 days and staying there for over 3 weeks time. Of course most users of anabolics will not find adequate benefit in the use of this steady-point dose, so this product is normally injected once a week, making the very lowest dose higher than half the peak dose at any given time. This is roughly the starting blood level as well. A long-acting testosterone ester is a must-have in any mass-building cycle. As such this is a very decent product.

A long-acting testosterone ester may be the best for all your mass-building needs, but its not an easy product to use. Because of the extreme length of action (3-4 weeks) one cannot easily solve occurring problems by simply discontinuing the product, as it will continue to act and aggravate side-effects over extended periods of time. In regards to damage control and post-cycle therapy, some familiarity with the use of ancillary drugs is required prior to using a long-acting testosterone product. Nolvadex and Proviron will come in very handy in such cases and post-cycle HCG and clomid or Nolvadex will be required as well to help restore natural testosterone. Frequency of side-effects is probably highest with this type of product.

However, over the years, as with every hormone, testosterone or other anabolic steroids has also been given for many other conditions and purposes besides replacement, with variable success but higher rates of side effects or problems. Examples include infertility, lack of libido or erectile dysfunction, osteoporosis, penile enlargement, height growth, bone marrow stimulation and reversal of anemia, and even appetite stimulation. By the late 1940s testosterone was being touted as an anti-aging wonder drug (e.g., see Paul de Kruif's The Male Hormone) in exactly the same way that growth hormone is being described today.

Replacement therapy can take the form of injectable depots, transdermal patches and gels, subcutaneous pellets and oral therapy. Adverse effects of testosterone supplementation include minor side effects such as acne and oily skin, and more significant complications such as increased hematocrit, exacerbation of sleep apnea and acceleration of pre-existing prostate cancer growth. Testosterone also causes suppression of spermatogenesis and can lead to infertility. It is recommended that physicians screen for prostate cancer with a digital rectal exam and PSA (prostate specific antigen) level prior to initiating therapy, and monitor hematocrit and PSA levels closely during therapy.

Before taking any prescription medicine, it is important that you consult your doctor!