GHRP-2 raises GH in humans, very quickly and very sharply. It also makes people eat more. But no trial has shown that it builds muscle or speeds recovery in healthy adults. The best available long-term trial, involving 126 GH-deficient children over 48 weeks, even found an increase in GH without any effect on growth.
That is the paradox of this molecule. It is one of the best-studied members of its family, and those very studies dismantle its sports-performance promise. GHRP-2 is an excellent tool for testing a pituitary gland. Nothing shows that it makes a biceps bigger.
In France, the Public Medicines Database contained no medicinal product based on GHRP-2 or pralmorelin when checked on October 12, 2026. In sport, the World Anti-Doping Agency’s 2026 list explicitly names it as prohibited at all times.
GHRP-2 and pralmorelin: identity and mechanism
GHRP-2, short for growth hormone-releasing peptide-2, is a small synthetic peptide comprising six amino acids, including one non-natural amino acid and several D forms absent from human proteins. Its international name is pralmorelin. It is the same molecule, not a “pharmaceutical” version of a different product.
It is a secretagogue: it contains no growth hormone but prompts the pituitary gland to release it. It acts on GHSR-1a, the receptor for ghrelin, the hunger hormone. Hence its two best-measured effects in humans: a GH spike and increased appetite.
In regulatory terms, pralmorelin has an unusual status for a peptide in this family. It is registered in Japan under the trade name GHRP, in the category of diagnostic reagents for endocrine function. It is used to check whether a patient’s pituitary gland can still release GH and ACTH. It is not a treatment, much less a performance product. Treatment projects were launched for short stature in children and GH deficiency. The Japanese registry consulted lists only diagnostic use.
GHRP-2 is not interchangeable with related peptides. GHRP-6 is its predecessor, of which it is a super-analogue; ipamorelin is considered more selective, while CJC-1295 acts on a different receptor. Results for one cannot be transferred to another.
Human trials: populations, routes and measured outcomes
The table below brings together studies that directly address the commercial promises. Older publications were consulted through their indexed abstracts, which limits detailed analysis of adverse effects.
| Study | Population and exposure | Measured outcome and result | Limitation for sport |
|---|---|---|---|
| Arvat et al., 1997 | 6 healthy adults aged 22–27, single intravenous injection, 1 and 2 µg/kg | Large increase in GH; increases in prolactin, ACTH and cortisol | Measurements over a few hours, no muscle outcomes |
| Mericq et al., 1998 | 6 GH-deficient children, daily subcutaneous injections for 8 months | Increased nighttime GH, unchanged IGF-1 and IGFBP-3, higher growth rate without a placebo group | Very small sample, no adults, no muscle outcomes |
| Van den Berghe et al., 1999 | 14 patients in prolonged intensive care, GHRP-2 and TRH infusion for 5 days versus placebo | Normalized IGF-1, osteocalcin +19%, lower urea-to-creatinine ratio | Critically ill patients, combination of two hormones, blood markers |
| Van den Berghe et al., 2002 | 33 men in prolonged intensive care, GHRP-2 alone or in combination, 5 days | GHRP-2 alone: reactivated GH and IGF-1, but no reduction in protein breakdown | Favorable metabolic effects appeared only with combinations |
| Laferrère et al., 2005 | 7 lean, healthy men, 270 min subcutaneous infusion versus saline | Intake at an unrestricted meal increased by 35.9% on average, with an increase in all seven men | Acute effect on one meal, no body-composition measurements |
| Laferrère et al., 2006 | 19 healthy adults, 10 lean and 9 obese, two doses versus placebo, double-blind | Intake at an unrestricted meal +10.2% at the low dose and +33.5% at the high dose | Same limitation: only one meal measured |
| Tanaka et al., 2014 | 126 GH-deficient children, nasal spray twice daily for 48 weeks, double-blind versus placebo | No difference in growth or IGF-1 between the three groups | Children, nasal route, but the only long-term controlled trial with a concrete outcome |
Two findings stand out. First, no study examined athletes, strength, lean mass or recovery after exercise. Second, the only long-term, controlled trial large enough to draw a conclusion was negative for its primary outcome.
GH and appetite: why these are not muscle outcomes
A GH spike is not meaningful exposure
Peptide marketing boils down to a shortcut: GH drives growth and tissue building, so anything that raises GH drives growth and tissue building. The 2014 Japanese trial cuts that shortcut dead. The children received a product capable of raising their GH—they were selected precisely because they responded to it—and after 48 weeks their growth had not changed compared with placebo. Neither had their IGF-1, the messenger that relays GH’s effects to tissues.
The authors suggest a simple explanation: a brief spike does not provide enough GH in the bloodstream over the day to produce a biological effect. The 1998 Chilean trial pointed in the same direction: increased nighttime GH, unchanged IGF-1 and a short-lived effect from each injection.
Evidence chain
From GH spike to outcome
- GH spike after GHRP-2: observed
- Sustained increase in IGF-1: not observed
- Effect on growth or muscle: not demonstrated
This result concerns children and a nasal spray. It does not prove that injected GHRP-2 would be useless in adults. It proves that a rise in GH alone is not evidence of efficacy. Stores using a GH curve as a sales pitch are selling exactly what this trial refuted.
Eating more is not recovery
The effect on appetite is real and reproducible. In both Laferrère trials, a four-and-a-half-hour infusion made participants eat about one-third more at the buffet, without changing the macronutrient distribution. That is no surprise: GHRP-2 mimics ghrelin, whose role is precisely that.
This finding is relevant to research on appetite disorders. It says nothing about muscle. Eating more can support muscle gain or fat gain, depending on training and the rest of the diet. For an athlete trying to cut body fat, a product that stimulates appetite actually works against the goal.
The “anabolic” effects come from intensive care
The only published favorable metabolic markers come from the Leuven team’s patients in prolonged intensive care. These patients, averaging 68 years of age and 40 days in intensive care, had a severely suppressed GH axis. Correcting a profound hormonal deficiency in a sick patient is nothing like adding a stimulant in a healthy adult whose axis works normally.
Even in that setting, the 2002 trial shows that GHRP-2 alone reactivated GH and IGF-1 without reducing protein breakdown. The anticatabolic effect appeared only in combination with TRH, or with TRH and GnRH. GHRP-2 alone also increased lactate and white blood cells on the fifth day.
Research doses: no validated sports protocol
The studies use very different exposures: a single intravenous injection for a test, a continuous infusion lasting a few hours for appetite, a five-day infusion in intensive care, and daily injections or a nasal spray in children. Each addresses a specific question in a medical setting with monitoring.
None describes a sports “cycle.” The regimens circulating on forums and sales websites, involving several injections a day for weeks, match no identified trial. Turning a research exposure into a personal protocol means keeping the syringe and throwing away the study.
I give no dose for use here because none has been validated for this purpose.
Endocrine risks, unknowns and contaminated products
What is documented
GHRP-2 is not selective. In healthy adults, Arvat’s study shows increases in prolactin, ACTH and cortisol after a single injection, with stimulation of the cortisol axis comparable to that produced by CRH, the hormone that controls this axis. This is precisely why Japanese endocrinologists use it to test ACTH reserve.
In April 2026, the FDA classifies GHRP-2 among substances that may present significant risks when used in compounded preparations, by injection or nasal administration. It cites an immunogenicity risk related to peptide aggregates and impurities, and the complexity of analyzing a peptide containing a non-natural amino acid. It also mentions reports of serious events in patients who received GHRP-2: increased insulin requirements to control blood glucose, deaths in intensive-care patients, infection and pancreatitis. Causality has not been established. These reports do not provide a numerical risk estimate for an athlete, but they contradict the idea of a “gentle” molecule.
What remains unknown
Three levels must be kept distinct:
- Observed: acute increases in GH, prolactin, ACTH, cortisol and appetite.
- Reported without established causality: blood glucose disturbances and serious events reported by the FDA in patient populations.
- Unknown: effects of repeated use over months in healthy adults, interactions with other peptides or steroids, and long-term consequences for glucose metabolism.
Having no symptoms answers none of these unknowns. It measures neither blood glucose nor prolactin nor the quality of the vial.
The vial is not the trial
The trials used pharmaceutical-quality peptide. The sports market sells something else. The Cologne anti-doping laboratory identified GHRP-2, about 50 µg per tablet, in a product sold as an over-the-counter dietary supplement. The Italian National Institute of Health found it in seized, unlabeled vials. In Poland, a seized vial contained a novel GHRP-2 analogue, modified by adding glycine—a molecule for which no human data exist.
An HPLC certificate does not solve this problem. It describes the chemical purity of a sample, not sterility, endotoxins or the vial you receive. Details are in the guide to contamination and sterility of peptides sold online · FR.
Status in France and anti-doping: dated checks
Medicine: no French authorization found
On October 12, 2026, the medicinal-product and composition files in the Public Medicines Database, updated on September 29, 2026, were searched for the terms GHRP, pralmoréline, pralmorelin, KP-102 and growth hormone releasing. No matches. This database mainly describes medicines currently marketed or recently discontinued. The absence of results does not prove that no research framework exists. It shows that no French medicine based on GHRP-2 is available to a patient, much less an athlete.
The ANSM alert of July 2, 2026, relayed by the French National Order of Pharmacists, urges people not to buy or use peptides sold online outside official channels. It targets the family, not GHRP-2 specifically. The Public Health Code, Article L. 5121-8, requires authorization before a medicine can be placed on the market. A “research use only” label does not replace that authorization or make injection into a person legitimate.
Sport: prohibited at all times
The World Anti-Doping Agency’s 2026 Prohibited List, effective since January 1, 2026, names “GHRP-2 (pralmorelin)” in section S2.2.4 among substances prohibited both in and out of competition. Anti-doping laboratories have been able to detect it and its metabolite in urine since 2010. An athlete registered with a sports federation who uses it risks sanctions, regardless of any effect on performance.
Differences from ipamorelin and CJC-1295
Sellers often present these peptides as variants of the same product. They do not all act at the same site:
- GHRP-2 and GHRP-6: ghrelin-receptor agonists with strong effects on GH, low selectivity, and effects on appetite, prolactin and cortisol. GHRP-2 has the advantage of a more extensive human evidence base, which contains no evidence of sports benefits.
- Ipamorelin: the same receptor, considered more selective for GH, but mainly on the basis of animal data and acute exposures.
- CJC-1295: an analogue of GHRH, the other signal controlling GH, with a much longer duration of action.
The GHRP and CJC mix, sold as a “synergy,” combines two real mechanisms. Combining them in healthy adults has not been validated for muscle outcomes. The full analysis is in the guide to ipamorelin and CJC-1295. For the whole family, see peptides in bodybuilding: effects and risks.
What to discuss with a doctor instead of injecting yourself
If a peptide appeals to you, there is often a real problem behind it: persistent fatigue, stalled training progress, loss of appetite or a lingering injury. That problem deserves a diagnosis, not a vial.
Some useful questions to ask at your appointment:
- Do my symptoms warrant hormone testing, and which tests?
- If GH deficiency is suspected, which stimulation test suits my situation?
- Is my recovery limited by sleep, nutrition or training load?
- Do the products I already take affect my blood glucose or hormones?
True adult GH deficiency is diagnosed through a stimulation test in a specialist setting. Ironically, in Japan, this test can use pralmorelin. In that setting, GHRP-2 belongs: a single injection, under supervision, to answer a medical question.
Diabetes, pituitary or adrenal disease, a history of tumors, pregnancy, breastfeeding and being under 18 make any personal experimentation particularly unjustified. After injecting a product of unknown origin, fever, spreading redness or pain at the injection site require prompt medical assessment. Difficulty breathing, facial swelling or feeling unwell require calling 15 or 112.
For approaches backed by evidence, the guide to growth hormone and longevity · FR explains what sleep and training already do for this axis.
The Verdict
I do not recommend this use. This verdict is independent of any affiliation: this page contains no purchase links.
Main sources
Older trials were consulted through their indexed abstracts. Institutional documents describe a regulatory framework, explicitly distinguished from use in sport.
