What Is TRT?
Testosterone Replacement Therapy (TRT) is FDA-approved for treating male hypogonadism (low testosterone) caused by testicular failure or hypothalamic-pituitary dysfunction. Testosterone cypionate and enanthate are the most commonly prescribed injectable esters, providing sustained testosterone levels with weekly or bi-weekly dosing. The TRAVERSE trial (5,200+ participants) confirmed cardiovascular safety in high-risk men when used as indicated.
Mechanism of Action
Exogenous testosterone supplementation replaces deficient endogenous production. Binds androgen receptors throughout the body, modulating gene expression for anabolic (muscle, bone) and androgenic (libido, mood) effects. Suppresses HPG axis via negative feedback.
Key Benefits
FDA-approved treatment for male hypogonadism restoring testosterone to physiological levels. Improves energy, libido, mood, muscle mass, bone density, and metabolic health. TRAVERSE trial confirmed cardiovascular safety in indicated patients.
Quick Reference
Member reference tables summarize the compound's research parameters.
Research Indications
Research Protocols
As reported in cited literature and research-community logs (see Research Citations below), not a personal dosing recommendation.
This member section describes parameters reported in the research literature.
Peptide Interactions
This member section summarizes reported compound interactions and evidence limitations.
Reported Research Time Points
This member section summarizes reported research time points.
Safety Notes
Included for harm-reduction awareness only, in the event this compound is encountered outside its labeled research use. Inclusion here does not imply RUO Codes endorses, recommends, or instructs human use.
This member section discusses research safety considerations and uncertainties.
Quality Indicators
Research Citations
- Cardiovascular Safety of Testosterone-Replacement Therapy
Lincoff, A.M., Bhasin, S., Flevaris, P., et al., 2023, New England Journal of Medicine - Effects of Testosterone Treatment in Older Men
Snyder, P.J., Bhasin, S., Cunningham, G.R., et al., 2016, New England Journal of Medicine - Testosterone supplementation and body composition: results from a meta-analysis of observational studies
Corona, G., Giagulli, V.A., Maseroli, E., et al., 2016, Journal of Endocrinological Investigation - Testosterone Therapy in Men With Hypogonadism: An Endocrine Society Clinical Practice Guideline
Bhasin, S., Brito, J.P., Cunningham, G.R., et al., 2018, Journal of Clinical Endocrinology & Metabolism - Evaluation and Management of Testosterone Deficiency: AUA Guideline
Mulhall, J.P., Trost, L.W., Brannigan, R.E., et al., 2018, Journal of Urology - Neoantigen-targeted CD8(+) T cell responses with PD-1 blockade therapy
Puig-Saus C, Sennino B, Peng S, 2023, Nature - Enhanced tumor retention and therapeutic potency in radionuclide therapy using GSH-induced self-assembling peptides
Song W, Feng Y, Li X, 2025, J Control Release - GRPR Expression in Metastatic Cancers: A Review of Potential Application of GRPR-Radioligand Therapy
Callaud A, Duan H, Hindié E, 2025, Semin Nucl Med - Chemical Synthesis of Interleukin-6 for Mirror-Image Screening
Aoki K, Maeda K, Inuki S, 2024, Bioconjug Chem - The deprotection of Lys(Mtt) revisited
Bourel L, Carion O, Gras-Masse H, 2000, J Pept Sci