Gonadorelin

Overview

Gonadorelin is a synthetic form of gonadotropin-releasing hormone (GnRH) used to maintain fertility and endogenous testosterone production during TRT. It is commonly co-prescribed with testosterone replacement therapy to prevent testicular atrophy and preserve HPG axis function.

Mechanism of Action

Gonadorelin mimics endogenous GnRH, binding to GnRH receptors on pituitary gonadotroph cells to stimulate the release of LH and FSH. Pulsatile administration maintains the natural hormonal cascade, preventing the testicular atrophy and infertility commonly associated with exogenous testosterone use.

Research Summary

Gonadorelin has been FDA-approved as a diagnostic agent (Factrel) for pituitary function assessment. Clinical use alongside TRT has shown preservation of intratesticular testosterone levels and sperm production. It has largely replaced hCG in TRT protocols at many hormone clinics following hCG supply constraints.

Dosing Information

Reported Side Effects

• Injection site reactions
• Headache
• Nausea
• Flushing
• Abdominal discomfort

Research References

• Gonadorelin (GnRH) for the preservation of fertility in men on testosterone therapy (2019)
• Maintaining fertility during testosterone replacement therapy (2015)
• Pulsatile GnRH therapy for hypothalamic amenorrhea and male hypogonadotropic hypogonadism (2010)