Gonadorelin
Also known as: GnRH, Factrel, Lutrepulse, LHRH
A synthetic version of the body's natural gonadotropin-releasing hormone (GnRH). It was previously FDA-approved under the brand names Factrel and Lutrepulse (both discontinued). It is now widely available through compounding pharmacies, especially for men on testosterone therapy who want to maintain fertility.
How it works
Gonadorelin mimics the body's natural GnRH, which is released in pulses from the hypothalamus. When given in the right pattern, it stimulates the pituitary gland to release LH (luteinizing hormone) and FSH (follicle-stimulating hormone). LH tells the testes to make testosterone and FSH supports sperm production. It became a popular HCG alternative after HCG availability was restricted.
Common uses
- Fertility preservation during testosterone replacement therapy (TRT)
- Maintaining testicular function and size on TRT
- Pituitary function testing (diagnostic)
- HCG alternative for men on testosterone
Side effects
- Injection site reactions (redness, swelling)
- Headache
- Nausea
- Abdominal discomfort
- Flushing
- Allergic reactions (rare)
Key research
- Previously FDA-approved as Factrel (diagnostic) and Lutrepulse (therapeutic pulsatile dosing for fertility)
- Clinical use shows maintained LH and FSH levels in men on TRT when dosed at 100-200mcg subcutaneously twice weekly
- Studies support its role as an effective HCG alternative for testicular stimulation during testosterone therapy
Safety notes
- Category 1 peptide, meaning it can be legally compounded by licensed pharmacies with a prescription
- Original FDA-approved versions (Factrel, Lutrepulse) have been discontinued
- Pulsatile dosing is important for proper effect. Continuous high-dose exposure can actually suppress LH/FSH
- Requires monitoring of hormone levels by a healthcare provider
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