GH Secretagogue · Ipamorelin

Ipamorelin

Half-life
Typical route
Subcutaneous injection
Evidence rank
Moderate
Studies indexed

Evidence-based guide to Ipamorelin for growth hormone optimization — mechanism of action, clinical research, dosing protocols, side effects, and safety.

Research OnlyModerate Evidence
Written by dr-sarah-chenReviewed by Healthier Rx Editorial Board5 min read
Quick Facts
TypeGH Secretagogue
FDA StatusResearch Only
Evidence LevelModerate Evidence
Typical Dose100-300mcg
Frequency1-2x daily
Cycle Length8-12 weeks
Key GoalsMuscle Growth, Recovery, Anti-Aging

How It Works

Ipamorelin is a synthetic pentapeptide growth hormone secretagogue (GHS) that was first described in 1998 by Novo Nordisk. It consists of five amino acids (Aib-His-D-2-Nal-D-Phe-Lys-NH2) and acts as a selective agonist of the growth hormone secretagogue receptor (GHS-R1a), also known as the ghrelin receptor.

What sets Ipamorelin apart from other GH secretagogues like GHRP-6 and GHRP-2 is its remarkable selectivity. Studies have demonstrated that Ipamorelin stimulates GH release in a dose-dependent manner without significantly elevating ACTH, cortisol, prolactin, or aldosterone — even at doses far exceeding those needed for GH release. This selective profile makes it one of the best-tolerated GH peptides available.

Ipamorelin produces acute GH pulses that mimic natural pulsatile GH secretion. When combined with a GHRH analog such as CJC-1295 without DAC, the two peptides stimulate GH release through complementary pathways — GHRH receptor activation and ghrelin receptor activation — resulting in a synergistic and amplified GH pulse significantly greater than either peptide alone.

Benefits

  • Selective GH release — does not significantly elevate cortisol, prolactin, or appetite
  • Improved body composition — increased lean mass and reduced body fat
  • Enhanced recovery — faster tissue repair and reduced muscle soreness
  • Better sleep quality — deeper, more restorative sleep through GH optimization
  • Anti-aging effects — improved skin, energy, and overall vitality
  • Synergistic with GHRH peptides — particularly effective when stacked with CJC-1295

Side Effects

  • Very well-tolerated with the cleanest side-effect profile among GH secretagogues
  • Injection site reactions — redness, mild pain (common)
  • Headache — occasional, usually transient
  • Mild water retention — typically resolves after first 1-2 weeks
  • Tingling or numbness — mild paresthesia in some users
  • Light-headedness — occasionally reported immediately post-injection
  • No significant cortisol or prolactin elevation at standard doses

Dosing Protocol

ParameterDetails
Standard Dose100-300mcg per injection
Frequency1-2 times daily
AdministrationSubcutaneous injection
TimingBedtime (primary) and/or upon waking, on empty stomach
Cycle Length8-12 weeks on, 4 weeks off
Common StackCombined with CJC-1295 no DAC 100-200mcg at same times
FastingNo food 2+ hours before or 30 minutes after injection

What You Will Need

  • Ipamorelin lyophilized vial (typically 2mg or 5mg)
  • Bacteriostatic water (30mL)
  • Insulin syringes (1mL, 29-31ga)
  • Alcohol swabs
  • Sharps container

Evidence

Key Research

Peer-reviewed findings from PubMed, summarized for clinical context.

  1. European Journal of Endocrinology (1999) · PMID 10580762

    Characterization of Ipamorelin as the first GH secretagogue with selective GH release and no significant effect on ACTH, cortisol, or prolactin.

  2. Hormone Research in Paediatrics (2012) · PMID 22846232

    Phase 1 study demonstrating dose-dependent GH release with favorable safety and tolerability profile.

  3. European Surgical Research (2008) · PMID 18765947

    Clinical evidence of Ipamorelin's GH-releasing effects and tolerability in a surgical patient population.

Frequently Asked Questions

References

  1. Ipamorelin, the first selective growth hormone secretagogueEuropean Journal of Endocrinology (1999). PMID: 10580762 · PubMed
  2. Safety and pharmacokinetics of single and multiple ascending doses of the growth hormone secretagogue IpamorelinHormone Research in Paediatrics (2012). PMID: 22846232 · PubMed
  3. Ipamorelin as a new growth hormone releasing peptide in the treatment of postoperative ileusEuropean Surgical Research (2008). PMID: 18765947 · PubMed

Protocols Featuring Ipamorelin

Medical Disclaimer

This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting any new treatment or protocol. Read our full medical disclaimer.