All peptides / Muscle and bone
GHRP-2
GHRP / ghrelin agonist
Also Pralmorelin, GHRP2, GHRP 2, Growth hormone releasing peptide-2, Growth hormone-releasing peptide 2, KP-102
- Evidence
- CAnimal and cell studies
- FDA status
- Not approvedas of 2026-10-26
- Route
- Injection
- Studies cited
- 3 human0 animal or cell
It is sold as a growth hormone booster for muscle, fat loss and recovery. Small studies show it raises growth hormone, but the effect fades and no one has tested muscle or health results.
Sold for
GHRP-2 is sold as a growth hormone booster for muscle, fat loss and recovery, often stacked with a GHRH analog.
Studies say
In small human studies GHRP-2 does release growth hormone and increases appetite, but repeated dosing attenuates the response without raising IGF-1, and no trial has measured a body-composition or health outcome, so the grade is C.
Why grade C. For the muscle-building and anti-aging use GHRP-2 is sold for, the cited human work is a 7-man appetite study and a 9-man five-day dosing study in which the growth hormone response faded and IGF-1 did not rise. The largest human study, 65 elderly patients, used GHRP-2 only as a diagnostic test. None measured body composition, strength or any health outcome. 123
FDA. GHRP-2, also called pralmorelin, is not approved by the FDA for any use and is sold online as a research chemical. It has been used in Japan as a diagnostic test for growth hormone deficiency, which is a separate regulatory system. In Japan the GHRP-2 test is still used to assess pituitary function. 2
Written from 3 cited sources. Fact-checked 2026-10-27: 12 claims checked, 3 corrected. Last refreshed 2026-10-27. Not physician reviewed.
What this means for you
- What people take it for
- Building muscle, burning fat and recovery
- Can a US doctor prescribe it?
- No. It is not approved and is sold as a research chemical.
- Properly tested in people?
- Not properly: animal or lab studies, or small uncontrolled human reports. The dosing studies had 7 to 9 men.
Evidence checklist
- Randomised controlled trial Small human studies; no body-composition trialno
- Human study over 100 people Largest cited study is a few menno
- More than one research group Article does not sayno information
- Clinical outcomes, not surrogate markers Hormone levels only, no health outcomeno
- Human safety data beyond case reports Short studies only; long-term unknownno
Drawn from the cited studies below. A dash means the sources give no information.
What it is
GHRP-2 is a lab-made peptide of six amino acids. It belongs to the growth hormone-releasing peptide family. Cyril Bowers' group developed it in the 1980s and 1990s. It looks nothing like the body's own growth hormone-releasing hormone (GHRH). Instead it mimics ghrelin, the stomach hormone that signals hunger. It binds the same receptor on pituitary cells. 12
Under the name pralmorelin, it was developed as a diagnostic agent. A single dose sharply raises growth hormone in healthy people. A weak rise can help confirm growth hormone deficiency. Its online sale as a performance peptide has nothing to do with that work. 2
How it works
GHRP-2 activates the ghrelin receptor (GHS-R1a) in the pituitary and hypothalamus. That receptor also drives appetite. A healthy-volunteer study found that a GHRP-2 infusion raised food intake at a buffet meal by about 36% compared with saline. Growth hormone rose at the same time. The authors used the peptide as a stand-in for ghrelin itself. 1
What human research shows
In seven lean men, a GHRP-2 infusion increased calorie intake. The mix of carbohydrate, fat and protein they chose did not change. This matches what ghrelin does. 1
A 1998 study gave nine healthy young men a daily injection of GHRP-2 under the skin for five days. Peak growth hormone fell from day 1 to day 5. IGF-1 did not increase. IGF-1 is the liver hormone through which growth hormone acts on muscle and bone. Osteocalcin, a marker of bone formation, did rise. That result cuts against the way the peptide is marketed. 3
| Study | Model | Finding |
|---|---|---|
| Laferrère 2005, appetite | Humans, n=7 lean men, crossover versus saline | GHRP-2 infusion raised food intake by about 36% and increased growth hormone. 1 |
| Nijland 1998, five-day GHRP-2 | Humans, n=9 healthy young men, daily injections over five days, uncontrolled | Growth hormone responses fell from day 1 to day 5 and IGF-1 did not rise, though osteocalcin, a bone-formation marker, increased. 3 |
| GHRP-2 test in elderly patients, 2023 | Humans, n=65 patients aged 65 and older before pituitary surgery, diagnostic study | The growth hormone response to a GHRP-2 test tracked adrenal function, supporting its use as a diagnostic stimulation test in Japan. 2 |
Safety
The short human studies report no serious adverse events. Increased hunger is the one steady effect. No one has studied longer use in people. So the effects on blood sugar, cortisol and prolactin over months are unknown. The related peptide hexarelin does raise cortisol and prolactin for a short time. This matters because GHRP-2 shares its receptor. Products sold online face no checks for purity or sterility. 13
Questions for your clinician
- Has GHRP-2 been tested for muscle or body composition in any trial?
- What is known about cortisol, prolactin and blood sugar with longer use?
- Why did IGF-1 not rise after repeated dosing?
Questions people ask
Is GHRP-2 FDA-approved?
No. GHRP-2 has no FDA approval for any use. Its diagnostic use as pralmorelin took place in Japan under a different regulator. Online products are sold as research chemicals. 2
Does GHRP-2 build muscle?
No study has measured muscle mass or strength after GHRP-2. The one repeated-dosing study in healthy men found that IGF-1 did not change over five days of injections. IGF-1 is the hormone that would have to rise for growth hormone to build tissue. 3
Why does GHRP-2 make people hungry?
It acts on the ghrelin receptor, and ghrelin is the body's main hunger signal. In a controlled study, men ate about a third more at a buffet during GHRP-2 infusion than during saline. 1
How is GHRP-2 different from GHRP-6, ipamorelin and hexarelin?
All four act on the same ghrelin receptor. GHRP-2 and hexarelin release growth hormone more strongly than GHRP-6. They also raise cortisol and prolactin. Ipamorelin was designed to release growth hormone without that cortisol effect. None of the four has a human outcome trial for muscle or aging. 12
Citations
- Laferrère 2005, Journal of Clinical Endocrinology and Metabolism: GHRP-2, like ghrelin, increases food intake in healthy men doi.org
- Growth Hormone and IGF Research 2023: GH response to the GHRP-2 test and pituitary function in 65 elderly patients before pituitary surgery doi.org
- Nijland 1998, Eur J Endocrinol: five days of subcutaneous GHRP-2 causes response attenuation without raising IGF-I in healthy young men pubmed.ncbi.nlm.nih.gov