Ipamorelin vs Triptorelin
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.
Ipamorelin
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 profileTriptorelin
Potent synthetic GnRH agonist approximately 100× more potent than native GnRH. Used clinically for prostate cancer, endometriosis, and precocious puberty via sustained suppression. A single low dose (100mcg IM) is studied as a 'PCT restart' strategy that exploits the initial LH/FSH flare before receptor desensitization sets in.
Full profile| Ipamorelin | Triptorelin | |
|---|---|---|
| Category | Performance & Growth Hormone | Performance & Growth Hormone |
| Also known as | NNC 26-0161, Ipamorelin acetate | GnRH agonist, Decapeptyl, Trelstar, D-Trp6-LHRH |
| Evidence | Investigational (in trials) | Research-stage |
| Dosing range | 100mcg–300mcg mcg, 1–3x daily (typically pre-sleep and/or pre-workout) | 50mcg–200mcg mcg, Single-dose for PCT restart; every 2–4 weeks for sustained suppression (clinical) |
| Administration | Subcutaneous injection, Intramuscular injection | Intramuscular injection, Subcutaneous injection |
| Key side effects | Water retention (mild), Tingling / numbness in extremities, Increased appetite, Headache (transient) | Initial testosterone surge followed by suppression (with repeated dosing), Hot flashes, Decreased libido, Bone density loss (long-term repeated dosing) |
| Cited sources | 3 references | 2 references |
Key differences
- Evidence level differs: Ipamorelin is investigational (in trials), while Triptorelin is research-stage.
- Administration: Ipamorelin — Subcutaneous injection, Intramuscular injection; Triptorelin — Intramuscular injection, Subcutaneous injection.
- Frequency: Ipamorelin is typically 1–3x daily (typically pre-sleep and/or pre-workout); Triptorelin is Single-dose for PCT restart; every 2–4 weeks for sustained suppression (clinical).
- Research depth: this profile cites 3 sources for Ipamorelin vs 2 for Triptorelin.
How each works
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.
Triptorelin
Triptorelin produces a biphasic response: an initial agonist surge of LH and FSH (the 'flare effect') followed by complete pituitary desensitization with continued use. The single-dose PCT protocol leverages only the initial flare to jumpstart testosterone production. Clinical data supports LH surges of 10–20× baseline within hours of the first dose.
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.