PeptiWiki
Hormonal

Ipamorelin

Selective GHRP with minimal side effects, stimulates growth hormone from the pituitary with high specificity.

FormulaC38H49N9O5 MW711.85 Da Injectable

Overview

Ipamorelin is a synthetic pentapeptide and growth hormone releasing peptide (GHRP) that selectively stimulates the release of growth hormone (GH) from the anterior pituitary gland. Developed in the late 1990s, it is one of the most selective GHRPs studied, notable for its minimal impact on cortisol, prolactin, and other hormones that many GHRPs elevate as side effects.

Its clean hormonal profile makes it a preferred research candidate for growth hormone optimization protocols, particularly when combined with a GHRH analogue such as CJC-1295 or Sermorelin for synergistic GH pulse amplification.

Mechanism of Action

Ipamorelin binds to and activates the ghrelin/growth hormone secretagogue receptor (GHS-R1a) in the pituitary gland, triggering a natural, pulsatile release of growth hormone. Key distinguishing features:

  • High Selectivity: Unlike GHRP-2 or GHRP-6, Ipamorelin does not significantly stimulate cortisol or prolactin release at research doses.
  • Pulsatile GH Release: Mimics the body's natural GH secretion pattern rather than causing a continuous flood.
  • Ghrelin Mimicry: Activates the same receptor as ghrelin but with greater specificity and without the appetite-stimulating effect common to other GHRPs.
  • Synergy with GHRH: Combined with a GHRH analogue (e.g., CJC-1295), creates synergistic GH release that is significantly greater than either compound alone.

Benefits

Potential benefits studied include: increased lean muscle mass, reduction in body fat, improved bone density, enhanced recovery and sleep quality, anti-aging effects via GH/IGF-1 axis stimulation.

Research Fields

Growth Hormone Deficiency Anti-Aging Muscle Building Bone Density Sleep Quality

Possible Side Effects

Generally well-tolerated. May cause transient water retention at higher doses. Mild injection site reactions possible. Unlike many GHRPs, does not cause significant cortisol, prolactin, or appetite changes.

Dosage & Protocol

Common research doses: 100–300 mcg per injection, 1–3 times daily via subcutaneous injection. Typically administered before sleep and/or training. Often stacked with CJC-1295 (2 mg/week) for amplified effect.

Also Known As

Ipamorelin Acetate NNC 26-0161