FDA Approved Growth Hormone Axis

GHRP-2

also known as: Pralmorelin, KP-102, Growth Hormone Releasing Peptide 2

A second-generation GHRP approved as a diagnostic agent in Japan, with more pronounced GH-releasing potency than GHRP-6 but a meaningful prolactin and cortisol rise at higher doses.

A synthetic hexapeptide ghrelin receptor agonist (D-Ala-D-β-Nal-Ala-Trp-D-Phe-Lys-NH2) that potently stimulates GH release, approved in Japan (as pralmorelin) for diagnostic evaluation of GH deficiency.

Mechanism of action

Agonist at GHS-R1a (ghrelin receptor) in the hypothalamus and anterior pituitary. Stimulates GH secretion with greater potency than ipamorelin but also produces dose-dependent increases in prolactin, cortisol, and ACTH — making it less "clean" for chronic community use despite strong diagnostic utility.

Primary uses

Diagnostic evaluation of adult GH deficiency (Japan)
Research on ghrelin signaling
Community GH-axis stacks (off-label, often in blends with CJC-1295)

Typical dosing

100–300 mcg 1–3 times daily (subcutaneous (community); intravenous 100 mcg for diagnostic test)

Community dosing only outside of the Japanese diagnostic indication.

Regulatory status

Approved in Japan as GHRP Kaken 100 (pralmorelin) for diagnostic evaluation of adult GH deficiency. Not FDA-approved in the United States.

References

[pubmed] Bowers CY. "GH releasing peptides—structure and kinetics." J Pediatr Endocrinol, 1993;6:21-31.
[pubmed] Chihara K, et al. "Diagnosis and treatment of adult growth hormone deficiency. GH Research Society Consensus Guidelines." Growth Horm IGF Res, 2007.

Related peptides

Ipamorelin

A selective ghrelin receptor agonist that stimulates GH release without the cortisol, prolactin, or ACTH spike seen with older GHRPs like GHRP-6.

GHRP-6

The prototype GHRP — a hexapeptide ghrelin receptor agonist notable for pronounced hunger stimulation and less favorable cortisol/prolactin profile than newer GHRPs.

Hexarelin

A high-potency GHRP studied for cardiac protection via a CD36-mediated pathway independent of GH release — but demonstrates clear tachyphylaxis with chronic use.

CJC-1295

A long-acting GHRH analog engineered with a DAC linker that binds serum albumin, extending half-life from minutes to approximately 8 days.

Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.