GHRP-2
Growth Hormone Releasing Peptide-2
aka Growth Hormone Releasing Peptide 2 · GHRP2 · Pralmorelin · KP-102
A second-generation GHS-R agonist that research associates with significant pulsatile growth hormone release.
Sequence
Mechanism of action
GHRP-2 works by binding to the growth hormone secretagogue receptor (GHS-R) on pituitary cells, stimulating the release of growth hormone (GH). It mimics ghrelin, a natural hormone that regulates appetite and energy balance, thereby increasing GH levels. This peptide also influences the hypothalamus to enhance GH secretion.
What the evidence actually shows
There are limited human trials on GHRP-2. Some studies suggest it increases GH levels and may improve body composition, but comprehensive clinical trials are lacking. More research is needed to confirm its efficacy and safety in humans.
Regulatory status
In the UK, GHRP-2 is classified as a research compound and is not approved for medical use by the MHRA.
Source ↗Pharmacokinetics
Dosing — what backs each figure
GHRP-2 (pralmorelin) has genuine published human data, but almost all of it is single-dose GH-stimulation testing: 100 microg intravenously as a validated diagnostic provocation test for adult GH deficiency, or 1 microg/kg intravenously / 1 microg/kg/h subcutaneously in physiology studies. No repeated therapeutic dosing regimen has been established, and chronic administration studies explicitly warn that GH responses desensitise depending on dose and frequency.
Single 100 microg intravenous dose after an overnight fast, with GH sampled over the following 2 hours; peak GH occurred within 60 min in all subjects. Validated as a diagnostic provocation test for adult GH deficiency
77 healthy subjects and 58 patients with GH deficiency (peak GH <3 microg/L on insulin tolerance test) · intravenous bolus
Bolus intravenous injection of GHRP-2 1 microg/kg body weight (or saline) given during sleep after 60 s of the third REM period; produced GH pulses within/around the upper physiological range and transient prolactin elevation, but no increase in slow-wave sleep
7 young healthy men · intravenous bolus
Subcutaneous infusion of GHRP-2 at 1 microg/kg/h (or saline) for 270 minutes, followed by an ad libitum buffet meal; subjects ate 35.9% more than on saline
7 lean healthy males · subcutaneous infusion
Chronic GHRP-2 administration for 7-30 days, alone or with GHRH; the authors state explicitly that whether GH response becomes desensitised depends in part on dosage and frequency of administration
normal younger and older men and women · not specified in abstract (parenteral)
- Dose
- Research literature cites ~100 to 300 mcg per dose
- Frequency
- 2-3x daily
Why this isn't evidence
The real human literature is a single 100 microg INTRAVENOUS bolus used as a one-off GH-deficiency diagnostic test, or weight-based 1 microg/kg IV / 1 microg/kg/h SC infusion - nobody has published a 100-300 microg subcutaneous dose given two or three times a day, and the '4-6 weeks on, then a break' desensitisation cycle in the notes is community convention.
This figure is shown because it is what circulates and what people search for — not because it is supported. Cycle lengths in particular tend to be convention copied between compounds rather than anything derived from a compound's own pharmacokinetics.
Handling and storage
Safety
- ·Increased appetite
- ·Water retention
- ·Joint pain
- ·Carpal tunnel syndrome
- ·Gynecomastia
- ·Pregnancy
- ·"Active cancer"
- ·Corticosteroids, which may blunt GH release
Increased appetite, water retention, transient prolactin/cortisol rise
Reported combinations
- ·CJC-1295, which may enhance GH release
- ·Somatostatin analogs, which inhibit GH release
Combination claims in this dataset are largely unsourced and should be treated as folk knowledge until a citation appears beside them.
References (4)
- Laferrere B, Abraham C, Russell CD, Bowers CY (2005) Growth hormone releasing peptide-2 (GHRP-2), like ghrelin, increases food intake in healthy men ↗J Clin Endocrinol MetabPMID 15699539DOI
Seven lean healthy men received subcutaneous GHRP-2 at 1 microgram/kg/h or saline for 270 minutes; food intake at a subsequent ad libitum buffet meal was 35.9 +/- 10.9% higher on GHRP-2, with every subject increasing intake.
- Kinoshita Y, Tominaga A, Usui S, Arita K, Sakoguchi T, Sugiyama K, Kurisu K (2013) The arginine and GHRP-2 tests as alternatives to the insulin tolerance test for the diagnosis of adult GH deficiency in Japanese patients: a comparison ↗Endocr JPMID 23079545DOI
Compared the insulin tolerance test, arginine test and GHRP-2 test in 71 pre-operative adults with pituitary tumours; the GHRP-2 test is one of the recommended alternatives to the ITT in Japan.
- Suzuki S, Ruike Y, Ishiwata K, Naito K, Igarashi K, Ishida A, et al. (2022) Clinical Usefulness of the Growth Hormone-Releasing Peptide-2 Test for Hypothalamic-Pituitary Disorder ↗J Endocr SocPMID 35795807DOI
Evaluated the GHRP-2 test - 'widely used for the diagnosis of patients with GHD' - for its ability to detect accompanying secondary adrenal insufficiency in hypothalamic-pituitary disorder.
- Okano M, Sato M, Ikekita A, Kageyama S (2010) Determination of growth hormone secretagogue pralmorelin (GHRP-2) and its metabolite in human urine by liquid chromatography/electrospray ionization tandem mass spectrometry ↗Rapid Commun Mass SpectromPMID 20552695DOI
Anti-doping analytical method for detecting pralmorelin and its metabolite in human urine, confirming its status as a doping-control target.
Data provenance
Chemistry and citations on this page were checked against primary sources on 2026-08-14. Values that could not be verified were left blank rather than filled with a plausible guess.
Could not verify
storage, reconstitution