What Is Ipamorelin? The Ghrelin-Receptor Peptide, Its One Human Trial, and Its Canadian Status

What is ipamorelin, and where does it stand in Canada? It is a five-residue synthetic peptide that acts at the ghrelin receptor, it has been tested in exactly one published efficacy trial in people, that trial missed its endpoint, and in April 2026 Health Canada named it among the unauthorized injectable peptides it had seized. Most Canadian pages selling it get at least one of those facts wrong, usually by filing it beside sermorelin and tesamorelin as though all of them did the same thing. They do not, and the difference changes what a certificate for ipamorelin can and cannot prove.

This guide covers what ipamorelin is as a molecule, how it differs from the GHRH analogues it is shelved beside, what Health Canada has said about it, what the animal work and the two human studies measured, its place in Canadian sport, and why its unnatural residues make identity testing the measurement that matters. It is written for laboratory and in-vitro research procurement. It reports what published studies recorded because that is the public evidence base, and it contains no dosing, administration or human-use guidance, and none should be inferred.

What Ipamorelin Is

Ipamorelin is a five-residue synthetic peptide with a C-terminal amide, developed at Novo Nordisk in the 1990s under the code NNC 26-0161. Its sequence is deliberately unnatural at three of the five positions.

Those values agree with PubChem CID 9831659. Reading the sequence left to right: Aib is alpha-aminoisobutyric acid, a residue with two methyl groups on the alpha carbon that no genetic code specifies; D-2-Nal is the D-isomer of 2-naphthylalanine, carrying a two-ring aromatic side chain; D-Phe is the mirror image of ordinary phenylalanine. Only histidine and lysine would be recognised from a cell's own proteins.

That design is the point. Unnatural residues and D-isomers resist the peptidases that would otherwise clear a five-residue peptide quickly, and the bulky aromatic at position three is what the receptor pocket accepts.

How Ipamorelin Works, and Why It Is Not a GHRH Analogue

Growth hormone release from the pituitary can be triggered through two separate receptors, and the compounds sold beside each other divide cleanly between them.

Sermorelin is GRF(1-29) amide, the first 29 residues of human growth hormone-releasing hormone. Tesamorelin is a modified GRF(1-44). Both act at the GHRH receptor. Ipamorelin is none of those things: a five-residue synthetic sequence with no resemblance to GHRH, acting at the receptor whose natural ligand is ghrelin.

Three practical consequences follow. The two classes are not interchangeable. Pairing one of each in a vial means two compounds acting at two different receptors, which is why ipamorelin is most often sold combined with a GHRH analogue. And they are not comparable on a milligram basis: a 29-residue fragment at 3357.9 g/mol and a 5-residue secretagogue at 711.9 g/mol contain very different numbers of molecules per milligram, so a price-per-milligram comparison across the classes compares nothing.

The word "selective" in the 1998 paper that introduced it, "Ipamorelin, the first selective growth hormone secretagogue", means something narrower than it is usually quoted as meaning. In the animal assays of that paper, ipamorelin released growth hormone without the rises in ACTH and cortisol that earlier secretagogues such as GHRP-6 produced. It describes a pharmacological profile in animals, not an outcome in people.

Ipamorelin vs CJC-1295

This is the comparison Canadian buyers ask about most, because the two are so often sold together. CJC-1295 is a modified GHRH(1-29) and acts at the GHRH receptor. Ipamorelin acts at the ghrelin receptor. One mimics the hypothalamic signal that tells the pituitary to release growth hormone; the other acts through a separate receptor on the same cells. They are different molecules from different chemical families, with different evidence: CJC-1295 with DAC has two published human pharmacology studies, and ipamorelin has a pharmacokinetic study and one failed efficacy trial. A combination vial is two analytical problems in one container, and its certificate should report each compound separately.

Ipamorelin in Canada

An active-ingredient search of the Health Canada Drug Product Database for ipamorelin returns no result, so there is no DIN and no Notice of Compliance, no pharmacy stocks it, and no product containing it may be sold as a drug in Canada.

Health Canada has also named it directly. Public advisory RA-81874, "Think twice before injecting peptides bought online: unauthorized products can seriously harm you", dated 9 April 2026, lists ipamorelin among thirteen examples of unauthorized injectable peptide drugs the department has seized, alongside CJC-1295, BPC-157, TB-500 and others. Health Canada's peptide guidance, updated 23 October 2026, carries the same list, states that injectable peptides are "always classified as drugs," and states that "it is illegal to sell or promote unauthorized health products in Canada." The general framework, including why a research-use label is not a licence for human use, is in are peptides legal in Canada.

The contrast with the GHRH analogues on the same shelf is worth knowing. Tesamorelin has held a Canadian DIN: the Drug Product Database carries two entries for Egrifta from Theratechnologies Inc., and both are now cancelled. Ipamorelin has never had one. A page that treats the whole shelf as equally unapproved is closer to right than one that treats it as equally approved, but neither is accurate.

Ipamorelin in Canadian sport

The WADA Prohibited List names ipamorelin explicitly under S2, among growth hormone secretagogues, prohibited at all times. Sport Integrity Canada (formerly the Canadian Centre for Ethics in Sport) applies that list to Canadian athletes.

What the Published Research Measured

The ipamorelin record is small: roughly fifty indexed papers, most of them reviews or chemistry. The primary studies that matter are few enough to list.

The 2014 trial is the one most pages omit, and it is the only efficacy trial in people. It was a multicentre, double-blind, placebo-controlled phase 2 study (ClinicalTrials.gov NCT00672074) testing ipamorelin for postoperative ileus, a stall in gut movement after abdominal surgery, chosen because ghrelin-receptor stimulation promotes gut motility. The authors reported that ipamorelin was well tolerated, with treatment-emergent adverse events in 87.5% of the ipamorelin group and 94.8% of the placebo group, and that there were "no significant differences between ipamorelin and placebo in the key and secondary efficacy analyses."

Regulators have read the same record cautiously. The US FDA's summary of safety concerns for nominated compounding substances notes that ipamorelin contains unnatural amino acids that complicate characterisation, and that a published study identified serious adverse events, including a death, when it was given intravenously for gastric motility. Neither regulator has assessed it as safe or effective for any use.

How to Verify an Ipamorelin Lot

Ipamorelin is the clearest case on the shelf for a point that applies to every short peptide: purity and identity are different questions, and here the usual purity test is close to blind to the thing most likely to be wrong.

A D-amino acid is nearly invisible to chromatography. D-Phe and L-Phe are mirror images with identical mass and nearly identical behaviour on a standard reverse-phase column. A lot synthesised with the L-isomer at position three or four would be the wrong molecule and could still report a high purity figure, because the chromatogram cannot see the difference and a mass spectrum alone cannot either. Only a chiral method, or comparison against a properly characterised reference standard, distinguishes them. The methods are covered in what actually proves a peptide sequence.

Standard amino acid analysis cannot report Aib or 2-Nal. It is calibrated for the twenty proteinogenic residues. Three of ipamorelin's five positions sit outside that set, so an analysis reporting only histidine and lysine has characterised two fifths of the molecule.

What a useful certificate reports. The monoisotopic mass is 711.3857 Da, and a mass spectrometric identity check against a reference standard confirms the molecule is the one named. Net peptide content is the second figure to ask for, because a purity ratio says nothing about how much peptide the vial holds.

Check the three things that make a certificate checkable:

1. The laboratory is named, with its report number.
2. The lot number on the document matches the vial in your hand.
3. The laboratory publishes a verification page where the report number can be looked up independently.

A certificate that names no laboratory, or whose lot number matches nothing on the container, describes some other material. Volta publishes its certificates as page images in its published certificate archive with the issuing laboratory's own verification link, and a certificate for the batch you receive is available on request. Those reports carry both HPLC and mass spectrometry results. The Canadian checklist is in how to verify a peptide in Canada, and the peptide testing labs directory lists independent laboratories that can run chiral work.

Ipamorelin Alone and Inside Multi-Component Vials

Ipamorelin is stocked on its own in 5 mg and 10 mg vials, with a compound hub at ipamorelin. It also appears in vials paired with a GHRH analogue: tesamorelin combinations at 10 mg and 20 mg, and a CJC-1295 no-DAC combination at 10 mg.

Those pairings are where the receptor distinction stops being academic. A vial holding ipamorelin plus a GHRH analogue contains two compounds acting at two different receptors, and its certificate reports each compound separately, with a purity and a net peptide content per component and no single purity for the vial, as covered in the analytical tradeoffs of a blend. The total milligram figure on the label is divided between them, so the quantity of ipamorelin is not the headline number.

Frequently Asked Questions

What is ipamorelin?

Ipamorelin is a synthetic pentapeptide with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2, developed at Novo Nordisk. Its CAS number is 170851-70-4, its formula is C38H49N9O5 and its average mass is 711.9 g/mol. It acts at the ghrelin receptor, GHS-R1a.

Is ipamorelin legal in Canada?

Ipamorelin has no Drug Identification Number and no Notice of Compliance, and Health Canada named it in its April 2026 advisory on unauthorized injectable peptides. Selling or promoting it for human use is illegal, and injectable peptides are always classified as drugs. It is not a controlled substance, and it is supplied as a research material for laboratory use only.

Is ipamorelin approved by Health Canada?

No. An active-ingredient search of the Drug Product Database returns no product containing it, and it has never held a Canadian authorization.

Has ipamorelin been tested in humans?

Yes, in two published studies. A 1999 study measured its pharmacokinetics in 40 healthy men and reported a terminal half-life of about 2 hours. A 2014 phase 2 trial in 114 bowel-surgery patients found no significant difference from placebo on its key efficacy endpoint. No trial has tested it for any other use.

Is ipamorelin a GHRH analogue like sermorelin?

No. Sermorelin and tesamorelin are analogues of growth hormone-releasing hormone and act at the GHRH receptor. Ipamorelin is an unrelated five-residue sequence acting at the ghrelin receptor.

What is the difference between ipamorelin and CJC-1295?

CJC-1295 is a modified GHRH(1-29) that acts at the GHRH receptor; ipamorelin is a five-residue secretagogue that acts at the ghrelin receptor. They are different molecules acting through different receptors, which is why they are often sold together in one vial.

What is the half-life of ipamorelin?

The 1999 human pharmacokinetic study reported a terminal half-life of about 2 hours, with the growth hormone response peaking at about 40 minutes.

Is ipamorelin banned in sport?

Yes. WADA names it under S2 as a growth hormone secretagogue, prohibited at all times.

Why can a purity figure miss an error in ipamorelin?

Two of its residues are D-isomers, which share the mass and nearly the chromatographic behaviour of their L counterparts. A lot built with the wrong isomer would be the wrong molecule and could still report a high purity figure.

Sources

• Raun K, Hansen BS, Johansen NL, et al. "Ipamorelin, the first selective growth hormone secretagogue." Eur J Endocrinol. 1998;139(5):552-561. PMID 9849822.
• Gobburu JV, Agersø H, Jusko WJ, Ynddal L. "Pharmacokinetic-pharmacodynamic modeling of ipamorelin, a growth hormone releasing peptide, in human volunteers." Pharm Res. 1999;16(9):1412-1416. PMID 10496658.
• Beck DE, Sweeney WB, McCarter MD; Ipamorelin 201 Study Group. "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. NCT00672074.
• Health Canada. Public advisory RA-81874, "Think twice before injecting peptides bought online: unauthorized products can seriously harm you." 9 April 2026.
• Health Canada. "Peptides: Overview" and "Peptides: Regulations and enforcement." Canada.ca, page details 23 October 2026.
• Health Canada Drug Product Database, active-ingredient search for ipamorelin: no result returned, checked 6 November 2026.
• Health Canada Drug Product Database, active-ingredient search for tesamorelin: two entries for EGRIFTA (Theratechnologies Inc.), DINs 02423677 and 02438712, both cancelled, checked 6 November 2026.
• US Food and Drug Administration. "Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks." Content current as of 22 April 2026.
• World Anti-Doping Agency. Prohibited List, section S2.
• PubChem Compound Summary, CID 9831659 (Ipamorelin). National Library of Medicine.