Does GHRP-2 work?
Not properly: animal or lab studies, or small uncontrolled human reports. The dosing studies had 7 to 9 men.
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
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
Evidence checklist
- Randomised controlled trial Small human studies; no body-composition trial
- Human study over 100 people Largest cited study is a few men
- More than one research group Article does not say
- Clinical outcomes, not surrogate markers Hormone levels only, no health outcome
- Human safety data beyond case reports Short studies only; long-term unknown
More on GHRP-2
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
Reference information only, not medical advice. Drawn from the GHRP-2 article, fact-checked against the cited sources. No dosing anywhere on this site.