Ipamorelin
A selective ghrelin-receptor pentapeptide studied for pulsatile growth-hormone release with relatively clean hormonal selectivity.
What Ipamorelin is
Ipamorelin is a pentapeptide growth hormone secretagogue that stimulates the ghrelin receptor (GHS-R1a). Researchers value it because early work suggested strong GH release with comparatively little stimulation of ACTH and cortisol at doses that still moved GH, an important selectivity contrast versus older GHRP scaffolds. Human pharmacokinetic-pharmacodynamic modeling and multiple preclinical growth studies established the core profile: a short circulating half-life, a discrete GH pulse, and dose-responsive somatotropic signaling. Ipamorelin remains a frequent reference compound in GH-axis, body-composition, and secretagogue-combination research. In research-supply contexts it is almost always handled as a lyophilized peptide for subcutaneous investigation. Content on this page is educational and research-use-only; ipamorelin is not an FDA-approved therapeutic product.
The record for Ipamorelin spans both animal work and human trials. Those two kinds of evidence do not carry equal weight, and the amounts below come from different settings.
How it works
Ipamorelin binds the growth hormone secretagogue receptor GHS-R1a, the same receptor activated by ghrelin. Receptor activation on pituitary somatotrophs promotes GH vesicle release. Because the peptide is relatively selective, experimental comparisons often highlight GH elevation with muted collateral HPA-axis activation versus earlier GHRPs. The short half-life produces a pulse-like GH exposure rather than a flat, prolonged elevation.
The research context
Endocrinology labs, sports-medicine research groups, and peptide pharmacology teams use ipamorelin when they need a selective GH secretagogue comparator. It also appears in protocol papers exploring GHRH-analogue plus GHRP co-administration. The audience is research personnel, not patients seeking treatment advice.
What the research examines
Fields of study, not claims. Investigation is not proof.
How it appears in the literature
Reported research amounts. These describe what was studied, not what anyone should do.
| Research context | Reported amount | Frequency | Route |
|---|---|---|---|
| Commonly cited in research and laboratory protocol discussions | 200 mcg – 300 mcg | 1–3 times daily | subcutaneous |
| Human IV PK/PD dose-escalation study (Gobburu et al.) | 300 mcg – 10 mg | single / investigational infusion | intravenous |
Handling & storage
Keep lyophilized vials cold, dry, and protected from light. After reconstitution with bacteriostatic water, refrigerate and avoid repeated warm-cold cycling; many labs aliquot to limit handling stress.
Notes on combined research
Ipamorelin is frequently discussed alongside GHRH analogues such as CJC-1295 (with or without DAC) or sermorelin because the two classes hit complementary nodes of GH release. Research stacks aim to amplify pulse amplitude while preserving physiologic timing. Literature comparisons sometimes include other GHRPs (GHRP-2, GHRP-6) when ranking selectivity and side-effect profiles.
Ipamorelin questions
Laboratory and secondary research summaries most often cite roughly 200–300 mcg per subcutaneous administration, sometimes repeated up to two or three times daily because of the short half-life. Published human PK work used IV mcg/kg infusions rather than a single universal SC chart.
A practical research reconstitution is 2–3 mL bacteriostatic water in a 5 mg or 10 mg vial. Example: 5 mg + 2.5 mL yields 200 mcg per 10 units on a U-100 syringe. Confirm arithmetic against your exact vial label.
Daily totals in informal research discussions often land near 200–900 mcg/day when split across one to three injections. Those figures are commonly cited reference ranges, not individualized medical directions.
Charts usually convert vial strength and diluent volume into mcg-per-tick-mark on an insulin syringe, then list once-, twice-, or thrice-daily pulse schedules. Use them only as research math aids.
Human pharmacokinetic modeling after IV infusion reported a terminal half-life around two hours, which explains multi-pulse experimental schedules.
In research settings it is commonly examined with GHRH analogues (for example CJC-1295/sermorelin) to probe synergistic GH release. Stack design belongs in controlled research protocols.
Foundational selectivity work reported minimal ACTH/cortisol stimulation at GH-releasing doses relative to several earlier secretagogues, which is a major reason it is studied as a cleaner GHS tool compound.
Peer-reviewed human data center on parenteral routes (IV infusion historically; SC in later research practice). Oral bioavailability is not the standard research route.
Read the research yourself
All of the below resolve to indexed papers on PubMed. We would rather cite less and cite accurately.