Growth Hormone & IGF Axis

Ipamorelin

Commonly used for
Muscle & StrengthRecoveryAthletic Performance
Ipamorelin is a selective growth hormone secretagogue (GHSR agonist) that stimulates endogenous GH release with minimal effects on cortisol and prolactin.
Mechanism of action: Ghrelin receptor agonist; Stimulates pulsatile GH release; Minimal effect on ACTH or cortisol
Proposed indications: Growth hormone deficiency; Recovery after training; Lean mass preservation; Sarcopenia; Healthy aging
Reported dosing range*: ~3-100 mcg/kg, intravenous infusion (pharmacokinetic study)
A pharmacokinetic study evaluated intravenous infusion doses of 4.21 to 140.45 nmol/kg (roughly 3 to 100 mcg/kg) over 15 minutes in healthy male volunteers (Gobburu JV et al. (1999). Pharmacokinetic-Pharmacodynamic Modeling of Ipamorelin, a Growth Hormone Releasing Peptide, in Human Volunteers. Pharmaceutical Research). This was an intravenous infusion pharmacokinetic study, not a subcutaneous-injection efficacy trial, and does not establish a wellness dosing convention.
*General range reported in available research or other sources -- not an individualized recommendation. Actual use should be supervised by a qualified provider.
Typical clinical dosing schedule: No established clinical dosing. Human use has been limited to early-phase research.
Administration: Subcutaneous injectionNo established clinical dosing
Compare with:
? Emerging / limited evidence
An "emerging / limited evidence" rating means rigorous research hasn't caught up yet -- not that this peptide doesn't work. Many peptides in this category are newer or simply understudied rather than proven ineffective.
Evidence rating: ⭐⭐☆☆☆Very limited human clinical data; most evidence is pharmacologic or preclinical.
Common side effects: Headache, Flushing, Injection-site irritation
Serious risks: Unknown due to lack of long-term human studies.
Monitoring: IGF-1, Blood glucose, Clinical adverse effects
Legal status: Not FDA-approved for human use. This is a research compound, not a medication — any use should only occur under the direction of a licensed healthcare provider, and its legal availability varies and changes frequently. Verify current status independently before considering use.
Regulatory status: Research peptide • Not FDA approved
Contraindications: Not established. Avoid in:; Pregnancy; Active malignancy; Uncontrolled endocrine disease
Pregnancy & breastfeeding: Avoid.
Smith RG, et al. (1997). Early characterization of ghrelin receptor agonists. Bowers CY. Reviews of growth hormone secretagogues.