Testosterone Enanthate

About

About Testosterone Enanthate

Testosterone enanthate is a long-acting esterified form of testosterone with a half-life of 4–5 days, making weekly or twice-weekly injections standard. It is FDA-approved for hypogonadism and is one of the most prescribed TRT formulations in the US. In optimization medicine it is used to restore and maintain testosterone to youthful physiologic levels. It requires injection but offers stable serum levels with proper dosing frequency.

Science

Mechanism of Action

Provides exogenous testosterone that binds androgen receptors throughout the body, restoring androgenic and anabolic signaling to tissues including muscle, bone, brain, and sexual organs.

Dosing

Typical Protocol

100–200 mg intramuscular or subcutaneous injection once or twice weekly; adjust based on trough serum testosterone levels.

⚠ Protocol information is for educational purposes only. Dosing must be determined by a licensed physician based on individual health status and goals.

Regulatory

Legal Status in 2026

FDA Approved

This compound has completed clinical trials and received formal FDA approval for one or more indications. It can be legally prescribed by licensed physicians, filled at any licensed pharmacy, and may be covered by insurance. Off-label use by physicians is also legal. This is the highest level of regulatory clearance available in the US.

Evidence

Evidence Tier

Clinical Trials

Evidence from randomized controlled trials (RCTs) or large observational studies in humans. This is the gold standard — effects have been measured in controlled conditions and results are peer-reviewed and reproducible.