Ipamorelin Dosage Guide
Phase I dose-finding data and GH secretagogue research protocols sourced directly from peer-reviewed literature. Presented as "dose used in Study X" — not a personal recommendation.
Research reference only. Ipamorelin is not FDA-approved for human use. This guide summarises peer-reviewed scientific literature. Not medical advice. See our full disclaimer.
At a Glance
Source: Raun K et al., Eur J Endocrinol, 1999. PMID 10097523
Phase I Human Study Data
Study design: This was a Phase I pharmacokinetic study evaluating single-dose safety and GH secretory response across five dose levels in healthy human volunteers. Multi-dose and long-term human data for Ipamorelin are not available in the published literature.
View on PubMed →Mechanism of Action
Ipamorelin is a selective ghrelin receptor (GHSR-1a) agonist — a synthetic pentapeptide growth hormone releasing peptide (GHRP). It stimulates pituitary somatotrophs to release GH in a pulsatile pattern via Gαq/11-coupled signaling and IP3-mediated calcium mobilization.
Unlike GHRP-2 and GHRP-6, Ipamorelin has a narrow selectivity profile — it stimulates GH release with minimal co-stimulation of cortisol, ACTH, or prolactin at GH-releasing doses. This makes it useful in research designs isolating GH secretagogue effects.
Ipamorelin is frequently studied in combination with CJC-1295 (a GHRH analogue), which acts synergistically by increasing pituitary sensitivity to secretagogue stimulation.
Reconstitution for Research Use
Ipamorelin is supplied as a lyophilised powder. Reconstitute with bacteriostatic water (0.9% benzyl alcohol in sterile water). A common research preparation for a 5 mg vial:
Add 1 mL bacteriostatic water → concentration 5,000 mcg/mL
Add 2 mL bacteriostatic water → concentration 2,500 mcg/mL
Store reconstituted peptide at 2–8°C. Use within 4–8 weeks. Protect from light. Do not freeze after reconstitution.
Frequently Asked Questions
What dose of Ipamorelin was used in the Phase I clinical study?
Raun K et al. (Eur J Endocrinol, 1999; PMID 10097523) tested single IV or SC doses of 1, 3, 10, 30, and 100 mcg/kg in a Phase I pharmacokinetic and safety study. This is the primary human dose-finding reference for Ipamorelin. The study was a single-administration PK design — not a multi-dose protocol.
How does Ipamorelin compare to GHRP-2 and GHRP-6?
Ipamorelin is more selective than GHRP-2 and GHRP-6. It produces minimal cortisol and prolactin elevation at doses that stimulate GH release, while GHRP-2 and GHRP-6 have stronger off-target effects on cortisol, ACTH, and prolactin. Ipamorelin's selectivity makes it preferable in studies where isolated GH secretagogue activity is the research objective.
Is Ipamorelin often combined with CJC-1295 in research protocols?
Yes. Ipamorelin (a GHSR agonist) and CJC-1295 (a GHRH analogue) act at different steps in the GH release pathway. CJC-1295 amplifies pituitary sensitivity to GH-releasing signals while Ipamorelin provides the pulsatile GHSR stimulus. Their combined use is a common research design for studying synergistic GH secretion.
What is Ipamorelin's mechanism of action?
Ipamorelin is a selective ghrelin receptor (GHSR-1a) agonist — a synthetic pentapeptide that stimulates pituitary somatotrophs to release GH via Gαq/11-coupled signaling and IP3-mediated calcium mobilization. It acts synergistically with GHRH input and does not significantly stimulate appetite at GH-releasing doses.