Testosteron depo is an ester of testosterone and enanthic acid. In the body, testosterone enanthate is hydrolysed to yield testosterone, resulting in no difference in action of esters and hormones. Testosterone main activity is: LH secretion regulation, spermatogenesis, male phenotype formation in the process of sexual differentiation and sexual maturity at puberty period in males.

Testosterone enanthate in oily solution is a depo preparation of slow absorption, resulting in prolonged hormone activity. Drug is primarily metabolized in the liver, same as natural hormone, without provoking liver damage. About 90% of administered drug is excreted in the urine (as testosterone and its metabolites conjugates). Only 6% is excreted in feces, mainly in non-conjugated form.

INDICATONS

male hypogonadal disorders of various etiology (primary hypogonadism, hypogonadothropic hypogonadism, including micropenis in early childhood and delayed puberty).
estrogen-dependant breast carcinoma in female pre-menopause and post-menopause (1-5 years after menopause),
refractory anemias of various etiology,
osteoporosis in androgen-deficiency individuals
Testosterone replacement should in theory approximate the natural, endogenous production of the hormone. The average male produces 4-7 mg of testosterone per day in a circadian pattern, with maximal plasma levels attained in early morning and minimal levels in the evening.8 However, the subtleties of pulsatile and diurnal rhythms are potentially difficult to imitate, and evidence suggests that different dose response curves exist for different androgen-dependent functions.9 The clinical rationale for treatment of testosterone deficiency may include:
-stabilizing or increasing bone density
-enhancing body composition by increasing muscle strength and reducing adipose
-improving energy and mood
-maintaining or restoring secondary sexual characteristics, libido and erectile function

Testosterone cypionate and enanthate are frequently used parenteral preparations that provide a safe means of hormone replacement in hypogonadal men. Testosterone is esterified to inhibit degradation and to make it soluble in oil-based injection vehicles that retain the drug in muscle tissue. In men 20-50 years of age, an intramuscular injection of 200 to 300 mg testosterone enanthate is generally sufficient to produce serum testosterone levels that are supranormal initially and fall into the normal ranges over the next 14 days. Fluctuations in testosterone levels may yield variations in libido, sexual function, energy, and mood. Some patients may be inconvenienced by the need for frequent testosterone injections. Increasing the dose to 300 to 400 mg may allow for maintenance of eugonadal levels of serum testosterone for up to three weeks, but higher doses will not lengthen the eugonadal period.