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Ipamorelin

low risk

Also: NNC 26-0161 · Ipamorelin acetate

Moderate Evidence Restricted

Ipamorelin is a selective GH secretagogue notable for minimal cortisol/prolactin elevation — making it the 'cleanest' GHRP. Human pharmacokinetic data exists. Most commonly combined with CJC-1295 for synergistic GH release.

Molecular Weight
711.9 Da
Formula
C38H49N9O5
Common Dosing
100–300 mcg per dose, 2–3x daily SC
Category
therapeutic
Last Reviewed
2025-01-15

Reported Benefits

Selective GH stimulation

Moderate Evidence 14 studies

Dose-dependent GH release without significant cortisol/prolactin spikes — confirmed in human and animal studies.

Body composition

Preliminary 5 studies

GH-mediated effects expected; limited direct human body composition data.

Mechanism of Action

Selective GHS-R1a agonist. Stimulates GH release with high selectivity — minimal ACTH, cortisol, or prolactin effects compared to other GHRPs.

Key Clinical Studies

Raun et al. (1998)

Controlled · Animal (dog/rat)

PubMed →

Selective GH release without cortisol/prolactin elevation

The Selectivity Advantage

Ipamorelin’s defining characteristic is selectivity. Unlike GHRP-2 and GHRP-6, it does not meaningfully elevate cortisol or prolactin. This makes it the preferred first-line secretagogue in GH optimization protocols.

Standard Stack

Ipamorelin + CJC-1295 (no DAC): different receptors (ghrelin vs. GHRH), synergistic effect, pulsatile pattern mimicking natural GH secretion.

Regulatory Status

Restricted

Safety Profile

Side Effects

  • Mild flushing
  • Headache
  • Lightheadedness
  • Water retention (high doses)

Contraindications

  • Active malignancy
  • Pregnancy

Drug Interactions

  • Somatostatin analogs
  • Glucocorticoids

Primary Uses

GH stimulationFat lossLean muscleRecovery

Weekly Briefing

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Disclaimer: This information is for educational and research purposes only. Not medical advice. Consult a qualified healthcare provider before using any compound.