Ipamorelin: Compound Reference for Researchers
A neutral reference sheet for ipamorelin, a synthetic pentapeptide that acts at the growth hormone secretagogue (ghrelin) receptor: structure, literature context and analytical notes.
For laboratory research use only. This page is educational. It does not describe uses, doses or effects in humans or animals, and nothing here is a recommendation. Our products are not for human or veterinary use.
At a glance
| Property | Value |
|---|---|
| Names | Ipamorelin; development code NNC 26-0161 |
| Class | Synthetic pentapeptide amide that acts as an agonist of the growth hormone secretagogue receptor (GHS-R1a, the ghrelin receptor); derived from GHRP-1 |
| Sequence | Aib-His-D-2Nal-D-Phe-Lys-NH2 (Aib = 2-aminoisobutyric acid; D-2Nal = D-2-naphthylalanine) |
| Molecular formula | C38H49N9O5 |
| Molecular weight | ≈ 711.9 g/mol (average); monoisotopic mass ≈ 711.39 Da |
| CAS number | 170851-70-4 |
| Form supplied | Lyophilized powder |
| Regulatory status | Supplied for laboratory research only; not an approved drug product. |
Sequence, formula and CAS number are the values listed by reference databases and suppliers (see references). The formula calculated from the sequence matches the listed formula. Compare any mass with the laboratory’s own result for the lot you hold.
What it is
Ipamorelin was described in 1998 as the first selective growth hormone secretagogue (reference 1). It is a five-residue peptide containing three non-natural building blocks: 2-aminoisobutyric acid, D-2-naphthylalanine and D-phenylalanine. Those unusual residues are part of what makes it different from older peptides in its family. It is made by chemical synthesis.
What the published literature looks like
Published work includes the original description (reference 1), studies of bone growth in rats (reference 2), a pharmacokinetic and pharmacodynamic study in human volunteers (reference 3), work in a rodent model of postoperative ileus (reference 4) and a small randomised proof-of-concept study in patients recovering from bowel resection (reference 5).
These are cited to show the breadth of the literature, not to endorse any conclusion in it.
How to read the evidence
- Mostly laboratory and early-phase work. Animal results do not establish effects in people, and the few human studies were small and specific.
- Studies describe particular preparations. They are not findings about research-use supplies.
- Quality matters. The non-natural, D-configured residues make identity testing important (see below).
Analytical notes
These points follow from the structure (see our guides to reading a COA and to HPLC and mass spectrometry).
- Detection wavelength. The naphthyl and phenyl groups give strong ultraviolet absorbance, so the peptide is easily seen at 220 nm and at higher wavelengths. Always note the wavelength with a purity figure.
- Mass check. Positive-mode electrospray mass spectrometry would be expected to show [M+H]+ at about m/z 712.39 and a doubly charged ion near m/z 356.70.
- Stereochemistry. The D-amino acids are part of the molecule, but ordinary mass spectrometry cannot tell a D-residue from an L-residue because they have the same mass. Chiral or stereochemical analysis is needed to confirm them.
- Chemistry. There is no methionine, cysteine, asparagine or glutamine, so the common oxidation and deamidation pathways do not apply.
Handling and storage
General laboratory guidance for lyophilized peptides applies: store cold, dry, sealed and protected from light, let the vial reach room temperature before opening, and avoid repeated freeze–thaw cycles for any solution. Details are in our guide to research peptide storage and stability.
HLX Peptide documentation
- Product: Ipamorelin (10 mg).
- Certificate: the certificate of analysis for lot IPA102026-01 (tested Oct 4, 2026 by BT Labs; HPLC purity 99.9%) is published on the product page and on our certificates of analysis page.
- Our process: Quality & Testing
- Related references: BPC-157 · Thymosin Beta-4 · GHK-Cu · Tesamorelin · MOTS-c · NAD+
References
- Raun K, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552–561. PMID 9849822.
- Johansen PB, et al. Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats. Growth Horm IGF Res. 1999;9(2):106–113. PMID 10373343.
- Gobburu JV, et al. Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers. Pharm Res. 1999;16(9):1412–1416. PMID 10496658.
- Venkova K, et al. Efficacy of ipamorelin, a novel ghrelin mimetic, in a rodent model of postoperative ileus. J Pharmacol Exp Ther. 2009;329(3):1110–1116. PMID 19289567.
- Beck DE, et al. Prospective, randomized, controlled, proof-of-concept study of the ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis. 2014;29(12):1527–1534. PMID 25331030.
- Chemical identifiers (sequence, formula, CAS): Ipamorelin (Wikipedia); Cayman Chemical product 39813. Masses calculated from the molecular formula.
Last reviewed October 5, 2026. All products are sold strictly for laboratory research use only. Not for human or veterinary use, and not a drug, food, or cosmetic.