Gonadorelin
Also known as: GnRH · Factrel
A synthetic form of GnRH used to stimulate LH and FSH — popular alongside TRT to maintain testicular function.
Gonadorelin at a glance
| Name | Gonadorelin |
|---|---|
| Also known as | GnRH, Factrel |
| Category | Hormonal & reproductive |
| Type | Peptide |
| Sequence | Synthetic gonadotropin-releasing hormone (decapeptide) |
| Typical dose | ~100–200 mcg |
| Frequency | Often 2–3× weekly (or as prescribed) |
| Route | Subcutaneous injection |
| Half-life | Very short (minutes). |
Overview
Gonadorelin is lab-made GnRH, the hormone that tells the pituitary to release LH and FSH. It is used clinically in fertility testing and treatment, and in the TRT community as an alternative to HCG for keeping the testes active during testosterone therapy.
How it’s thought to work
- Stimulates pituitary release of LH and FSH in a pulsatile fashion.
- Maintains testicular signaling that exogenous testosterone would otherwise suppress.
Researched uses
- Maintaining testicular function on TRT
- Fertility support and diagnostics
Commonly cited protocol
| Typical dose | ~100–200 mcg |
|---|---|
| Frequency | Often 2–3× weekly (or as prescribed) |
| Route | Subcutaneous injection |
| Notes | Very short half-life; frequent small doses mimic natural pulses. |
Reconstitution
Often a 5 mg vial. 5 mg with 2 mL water = 2.5 mg/mL, so 100 mcg = 4 units on a U-100 syringe.
Gonadorelin dosage calculator
The calculator below is pre-filled with Gonadorelin’s commonly cited vial size and dose. Adjust the vial amount, bacteriostatic water, or dose to match your own vial — it will show the exact insulin-syringe units to draw, the concentration, and how many doses the vial holds.
Add 5 mL of bacteriostatic water to your 5 mg vial. That gives you about 50 doses of 100 mcg. For each dose, draw 10 units into a 100-unit insulin syringe.
See the full Gonadorelin dosing chart (units for every dose & water amount), or open the full peptide calculator →
Cautions
- Prescription/compounded where used.
- Overuse can paradoxically downregulate the axis.
- Use under medical guidance, especially with TRT.
Gonadorelin FAQ
What is Gonadorelin?
A synthetic form of GnRH used to stimulate LH and FSH — popular alongside TRT to maintain testicular function.
How does Gonadorelin work?
Stimulates pituitary release of LH and FSH in a pulsatile fashion. Maintains testicular signaling that exogenous testosterone would otherwise suppress.
What is Gonadorelin used for?
Maintaining testicular function on TRT; Fertility support and diagnostics.
What is a typical Gonadorelin dose?
~100–200 mcg, Often 2–3× weekly (or as prescribed), Subcutaneous injection. This is a commonly cited figure for context only, not medical advice.
How do you reconstitute Gonadorelin?
Often a 5 mg vial. 5 mg with 2 mL water = 2.5 mg/mL, so 100 mcg = 4 units on a U-100 syringe.
What is the half-life of Gonadorelin?
Very short (minutes).