TRT & Hormone Optimization — Peptide Research Overview

Relevant Compounds

• Testosterone Cypionate — The most commonly prescribed form of testosterone for TRT in the US. FDA-approved for hypogonadism. Gold-standard exogenous testosterone delivery.
• Enclomiphene — Active trans-isomer of clomiphene. Stimulates endogenous testosterone production by blocking estrogen feedback at the hypothalamus. Fertility-preserving TRT alternative.
• Gonadorelin — GnRH analog used to maintain testicular function and fertility during TRT. Often co-prescribed with exogenous testosterone to prevent testicular atrophy.

What the Research Shows

Testosterone Cypionate

[Human Trial] Testosterone Cypionate is FDA-approved for primary and hypogonadotropic hypogonadism. Extensive clinical trial data (decades of data) demonstrates improvements in libido, energy, muscle mass, bone density, mood, and erythropoiesis. Standard dosing is 100–200 mg IM or subcutaneous every 7–14 days, titrated to target total testosterone of 600–900 ng/dL. Ongoing monitoring of hematocrit, PSA, and lipid panels is standard of care.

Enclomiphene

[Human Trial — Phase 3] Enclomiphene has completed Phase 3 trials for hypogonadism. It increases LH and FSH, stimulating natural testosterone production while maintaining spermatogenesis — a critical advantage over exogenous testosterone which suppresses both. Phase 3 data showed testosterone normalization in ~70% of patients with once-daily oral dosing. The FDA issued a Complete Response Letter (CRL) citing manufacturing concerns; it is used off-label through compounding pharmacies.

Gonadorelin

[Human Trial] Gonadorelin (GnRH) administered in pulsatile fashion stimulates pituitary LH and FSH release, maintaining testicular volume and function during TRT. FDA-approved for various endocrine indications. Common protocols use 100 mcg subcutaneous injections 2–3x weekly alongside testosterone. Evidence for fertility preservation during TRT is well-supported in clinical literature.

Evidence Summary