Testosterone Enanthate

Testosterone Enanthate is an esterified variant of the naturally occurring androgen and anabolic steroid, testosterone. It is a long-acting prodrug of testosterone, meaning it is broken down by the body over time to release active testosterone. It is primarily administered via intramuscular (IM) or subcutaneous (SC) injection.

Here is a detailed breakdown of the requested information:

Testosterone Enanthate (TE) Explained

• Detailed Explanation: Testosterone Enanthate is testosterone with an enanthate (heptanoate) ester group attached at the C17$\beta$ position. This esterification makes the compound more lipid-soluble and less polar, allowing it to be dissolved in oil and injected into muscle tissue or under the skin. Once injected, the oil acts as a depot, slowly releasing the testosterone ester into the bloodstream. Esterase enzymes then cleave the ester bond, releasing free, bioavailable testosterone. This mechanism provides a sustained release profile, resulting in more stable blood levels compared to un-esterified testosterone, but still with fluctuations (peaks and troughs).

• Other Names:

  • Generic Name: Testosterone heptanoate

  • Brand Names (Examples): Delatestryl, Xyosted, Andro LA, Everone, Testate, Androtardyl, Testinon, Testo-Enant.

Anabolic and Androgenic Ratio

Testosterone Enanthate is a prodrug of testosterone. Therefore, its intrinsic anabolic and androgenic properties are those of testosterone.

• Anabolic:Androgenic Ratio (AAR): 1:1

Benefits and Side Effects (Pros and Cons)

Testosterone Enanthate is used primarily for Androgen Replacement Therapy (ART) in males with conditions associated with a deficiency or absence of endogenous testosterone (hypogonadism).

Dosage and Frequency (Therapeutic Use)

Dosage is highly individualized and must be determined by a healthcare professional based on blood tests, response, and the specific condition being treated (e.g., primary hypogonadism, delayed puberty, or gender-affirming therapy).

• Typical Therapeutic Dosage and Frequency (IM injection): Generally ranges from 50 mg to 400 mg administered every 1 to 4 weeks. A common maintenance regimen for complete androgen replacement is 50 mg to 100 mg intramuscularly every 7 to 10 days to maintain relatively stable levels.

Pharmacokinetics

• Elimination Half-Life: Approximately 4.5 to 9 days (when administered as a depot IM injection).

• Detection Time (How many days/weeks): Detection time for performance-enhancing use can vary widely based on the dose, individual metabolism, injection frequency, and the specific drug test method used. WADA (World Anti-Doping Agency) studies indicate that testosterone esters can be detected for several days to weeks. For Testosterone Enanthate, the detection time is generally longer than the Propionate ester but shorter than the Undecanoate ester. As a general estimate, metabolites can be detectable for several weeks (often cited as up to 3-5 weeks) or more, but this is highly variable.

Sterogenic, Progestronic, and Prolactin Effects

• Sterogenic Affects (Estrogenic): High. Testosterone is a substrate for the aromatase enzyme, which converts it into the potent estrogen, estradiol (E2​). This leads to a high degree of estrogenic activity and is responsible for side effects like water retention and gynecomastia.

• Progestronic Affects: None. Testosterone and its esters do not bind significantly to the Progesterone Receptor (PR) and are not considered progestins.

• Prolactin Affects: Indirect/Possible. While Testosterone Enanthate itself is not a prolactin agonist, high estrogen levels (which result from testosterone aromatization) can indirectly stimulate prolactin release. Some studies have shown that prolonged administration of high doses of testosterone enanthate can significantly increase prolactin levels in some animal models, though the clinical significance is debated and usually associated with very high, non-therapeutic doses.