Gonadorelin vs Ipamorelin
A neutral, side-by-side comparison of two performance & growth hormone peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
Gonadorelin
Synthetic form of endogenous gonadotropin-releasing hormone (GnRH) that stimulates LH and FSH release from the anterior pituitary. Used in TRT protocols to maintain testicular function and prevent atrophy during exogenous testosterone administration. Preserves spermatogenesis and endogenous testosterone production capacity.
Full profileIpamorelin
Ipamorelin is a selective growth hormone secretagogue (GHS) and ghrelin receptor agonist. It stimulates GH release with high selectivity — minimal cortisol or prolactin elevation compared to older GHRPs. Widely used in research protocols for body composition, sleep quality, and recovery.
Full profile| Gonadorelin | Ipamorelin | |
|---|---|---|
| Category | Performance & Growth Hormone | Performance & Growth Hormone |
| Also known as | GnRH, gonadotropin-releasing hormone, Factrel, Lutrepulse | NNC 26-0161, Ipamorelin acetate |
| Evidence | Research-stage | Investigational (in trials) |
| Dosing range | 50mcg–200mcg mcg, 2–3x per week subcutaneous | 100mcg–300mcg mcg, 1–3x daily (typically pre-sleep and/or pre-workout) |
| Administration | Subcutaneous injection, Intranasal (pulsatile delivery) | Subcutaneous injection, Intramuscular injection |
| Key side effects | Injection site reactions, Headache, Nausea, Flushing | Water retention (mild), Tingling / numbness in extremities, Increased appetite, Headache (transient) |
| Cited sources | 2 references | 3 references |
Key differences
- Evidence level differs: Gonadorelin is research-stage, while Ipamorelin is investigational (in trials).
- Administration: Gonadorelin — Subcutaneous injection, Intranasal (pulsatile delivery); Ipamorelin — Subcutaneous injection, Intramuscular injection.
- Frequency: Gonadorelin is typically 2–3x per week subcutaneous; Ipamorelin is 1–3x daily (typically pre-sleep and/or pre-workout).
- Research depth: this profile cites 2 sources for Gonadorelin vs 3 for Ipamorelin.
How each works
Gonadorelin
Gonadorelin directly binds GnRH receptors in the anterior pituitary to trigger LH and FSH secretion, which in turn stimulates Leydig cells for testosterone production and maintains spermatogenesis. Used as a TRT adjunct, pulsatile gonadorelin administration mimics natural hypothalamic GnRH to prevent testicular suppression associated with exogenous androgen use.
Ipamorelin
Ipamorelin selectively stimulates GH release via the ghrelin receptor (GHS-R1a) without significantly elevating ACTH or cortisol — the feature that distinguishes it from GHRP-6 and GHRP-2 (Raun et al., 1998, in swine/rodent models). Human data are limited: a PK study in 40 volunteers established a ~2-hour half-life (Gobburu et al., 1999), and a Phase 2 trial for postoperative ileus (Beck et al., 2014) failed its primary endpoint. It is not FDA-approved, and claims about body composition or recovery are extrapolated from GH physiology, not human outcome trials.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.