Hexarelin vs GHRP-2: evidence, cost, and legality

Which is better, hexarelin or GHRP-2?

If the question is which peptide has the better documented human pharmacology, GHRP-2 wins: a validated 100 ug intravenous diagnostic test in 62 adults, a dose response study in 34 children, and a placebo controlled crossover in healthy men. If the question is which one a person could use as a therapy, neither: hexarelin's only long term study found the GH response attenuated by about 50% with no sustained IGF-1 rise, GHRP-2 has no chronic therapeutic trial and sits in FDA's 503B Category 2 for immunogenicity and adverse event concerns, and both are unscheduled for 503A compounding, unapproved, and WADA prohibited under S2. [1] [3] [8] [9] [11] [12] [13]

How do hexarelin and GHRP-2 compare?

Hexarelin and GHRP-2 compared by dimension
Dimension	Hexarelin	GHRP-2
Head-to-head evidence [1]	In a crossover study of healthy young adults, hexarelin released more GH than GHRH and raised prolactin, ACTH, and cortisol.	In the same study GHRP-2 also released more GH than GHRH with the same rise in prolactin, ACTH, and cortisol; the two peptides behaved similarly as acute GH stimuli.
Note: Arvat 1997 is a single dose pharmacology study, not a therapeutic trial. It establishes that the two peptides are pharmacologically interchangeable as acute GH releasers and says nothing about chronic use.
Evidence grade [2] [3] [7] [8] [9]	Human observational. Acute dose finding in healthy adults by intravenous, subcutaneous, intranasal, and oral routes (Ghigo 1994), a 16 week open treatment study (Rahim 1998), a sleep laboratory study, and a single dose cardiac surgery study. No randomized trial of a clinical outcome.	Human observational. Dose response in 34 short children (Pihoker 1995), a diagnostic validation study in 62 adults (Chihara 2007), and a double blind placebo controlled crossover of appetite in 7 healthy men (Laferrere 2005). The crossover is randomized but is a single dose physiology study, so it does not raise the grade.
Chronic use data [3] [9]	The only chronic human study: 1.5 mg subcutaneously twice daily for 16 weeks in healthy adults. The GH response to hexarelin fell by about half, IGF-1 did not rise durably, and the response recovered after washout.	No chronic therapeutic study in adults has been published. All human dosing is single intravenous doses or a short infusion; the subcutaneous regimens sold online come from no trial.
Note: Hexarelin's attenuation is the clearest evidence that continuous ghrelin receptor stimulation is self limiting; GHRP-2 has simply never been tested long enough to show whether the same happens.
Structure and mechanism [5] [6] [10] [11]	Methylated analog of GHRP-6 (His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2). Activates GHS-R1a and also binds CD36 on cardiac and vascular cells, the basis of rodent cardioprotection data and a single human bypass surgery study.	D-Ala-D-beta-Nal-Ala-Trp-D-Phe-Lys-NH2, containing an unnatural naphthylalanine residue. Activates GHS-R1a; FDA cited the unnatural amino acid as complicating characterization. No CD36 or cardiac data.
Side effects seen in studies [1] [4] [8] [11]	Rise in cortisol, ACTH, and prolactin with each dose; transient flushing after intravenous dosing; reduced slow wave sleep in a placebo controlled sleep study; increased hunger.	Rise in cortisol and prolactin; a 35.9% increase in ad libitum food intake in the placebo controlled crossover; flushing and sweating after intravenous dosing. FDA additionally cites reports of increased insulin requirements, pancreatitis, infection, and death in critically ill study subjects without established causality.
Regulatory status [11] [12]	Unscheduled. Never approved anywhere, never nominated for the 503A or 503B bulks lists, and absent from Category 2. There is no lawful basis for a compounding pharmacy to use it.	Not eligible. FDA placed GHRP-2 (injectable and nasal routes) in 503B Category 2 on September 29, 2023 and it remained there as of April 22, 2026; it has no 503A nomination. Pralmorelin is approved in Japan only as a diagnostic agent.
WADA status [13]	Prohibited at all times under section S2 as a growth hormone secretagogue.	Prohibited at all times under section S2; GHRP-2 is one of the GHRPs named on the list.
Routes studied [2] [7] [9]	Intravenous, subcutaneous, intranasal, and oral all produced GH release in the 1994 dose finding study, with intravenous 1 to 2 ug/kg producing the largest response.	Intravenous bolus and infusion in the diagnostic and physiology studies; intranasal in children. Subcutaneous use as sold has no published human data.
Cost and access [11] [12]	No licensed channel; hexarelin was never nominated for the 503A bulks list. Products sold as research chemicals are not lawful for human use and are not verified for identity or purity.	No licensed channel; GHRP-2 is in FDA's 503B Category 2. Products sold as research chemicals are not lawful for human use and are not verified for identity or purity.

Evidence grade and regulatory status

Pulled from each peptide’s own record, so it stays in step with the peptide pages.

Hexarelin and GHRP-2: grade, status, and cost
Attribute	Hexarelin	GHRP-2
Class	Synthetic hexapeptide growth hormone secretagogue (ghrelin receptor agonist), methylated analog of GHRP-6	Synthetic hexapeptide growth hormone secretagogue (ghrelin receptor agonist)
What it is	Potent lab-made growth hormone releaser with 1990s human data; the GH response fades with repeated use; never approved anywhere; WADA prohibited.	Lab-made peptide that triggers growth hormone through the hunger hormone (ghrelin) receptor; approved only as a diagnostic test in Japan; WADA prohibited.
Evidence	Evidence: Human observational evidence	Evidence: Human observational evidence
FDA status	Regulatory: Unscheduled	Regulatory: Not eligible for compounding
Compounding	Not FDA approved and never commercially developed to approval anywhere. Hexarelin does not appear on the FDA 503A or 503B bulks lists or in Category 2 as of the FDA pages current to April 2026, which means it has not been nominated and there is no lawful basis for a compounding pharmacy to use it. It was not part of the April 2026 Category 2 withdrawals or the July 2026 advisory committee review.	Not FDA approved for any use. FDA added GHRP-2 (for injectable and nasal routes) to the 503B Category 2 list on September 29, 2023, citing immunogenicity risk, an unnatural amino acid that complicates characterization, and reports of serious adverse events. As of the FDA page current to April 22, 2026, GHRP-2 remains in 503B Category 2 and has no 503A nomination or listing, so licensed compounding pharmacies have no lawful basis to compound it. It was not among the peptides withdrawn from Category 2 in April 2026. Pralmorelin is approved in Japan only as a diagnostic agent.
WADA	WADA: WADA prohibited	WADA: WADA prohibited
Routes	Intravenous (research studies), Subcutaneous injection (research studies and as sold), Intranasal and oral (research studies, lower bioavailability)	Intravenous bolus or infusion (diagnostic and research studies), Intranasal (research studies), Subcutaneous injection (as sold, not from published trials)
Typical cost	Not available through licensed US channels. Products sold as research chemicals are not lawful for human use and are not verified for identity or purity.	Not available through licensed US channels. Products sold as research chemicals are not lawful for human use and are not verified for identity or purity.
Last verified	Sep 22, 2026	Sep 22, 2026

Has hexarelin been tested directly against GHRP-2?

Direct comparisons of Hexarelin and GHRP-2
Study	Design and population	Outcome	Grade
Effects of GHRP-2 and hexarelin, two synthetic GH-releasing peptides, on GH, prolactin, ACTH and cortisol levels in man. Comparison with the effects of GHRH, TRH and hCRH1997 PMID 9285939	Crossover pharmacology study of single doses in healthy volunteersHealthy young adults	Both peptides released more GH than GHRH and raised prolactin, ACTH, and cortisol; no meaningful difference between hexarelin and GHRP-2 as acute stimuli	Evidence: Human observational evidence

What do hexarelin and GHRP-2 cost?

Typical cost of Hexarelin and GHRP-2
Dimension	Hexarelin	GHRP-2
Typical cost	Not available through licensed US channels. Products sold as research chemicals are not lawful for human use and are not verified for identity or purity.	Not available through licensed US channels. Products sold as research chemicals are not lawful for human use and are not verified for identity or purity.
Price detail	Price index in progress	Price index in progress

Where a price index exists, the range is the cash price per month across branded, compounded, and telehealth channels, without insurance. The cost pages give each channel separately with its sources. Otherwise the typical cost from the peptide record is shown. Legal access depends on your state: see peptide legality by state.

Frequently asked questions

Which releases more growth hormone, hexarelin or GHRP-2?

In the one direct comparison, both released more GH than GHRH after a single dose and the two were similar to each other. Hexarelin is often described as the more potent of the GHRP family, but the human crossover did not show a clinically meaningful gap, and in hexarelin's only chronic study the GH response fell by about half over 16 weeks. [1] [3]

Is either one legal to get from a compounding pharmacy in the United States?

No. Hexarelin has never been nominated for the FDA bulks lists, so no pharmacy has a basis to compound it. GHRP-2 was placed in 503B Category 2 in September 2023 and has no 503A listing, which means neither 503A pharmacies nor 503B outsourcing facilities can lawfully compound it. [11] [12]

Do they raise cortisol and prolactin?

Yes, both do with every dose. The crossover study found both hexarelin and GHRP-2 raised prolactin, ACTH, and cortisol alongside GH, which is a class effect of ghrelin receptor agonists that the GHRH analogs do not share. [1]

Which one increases appetite more?

Both are ghrelin mimetics and both increase hunger. GHRP-2 has the measured number: a 1 ug/kg per hour infusion raised ad libitum food intake by 35.9% in a placebo controlled crossover in healthy men. Hexarelin's hunger effect is reported but was not quantified in a controlled feeding study. [2] [8]

Can athletes use either?

No. Both are growth hormone secretagogues prohibited at all times under WADA section S2, in and out of competition. [13]

Does GHRP-2 have any approved use anywhere?

Only as a diagnostic. Pralmorelin (GHRP-2) is approved in Japan for testing growth hormone deficiency, where a 100 ug intravenous dose with a peak GH cutoff of 9 ng/mL separates severe adult GH deficiency from normal secretion. Hexarelin has no approved use in any country. [9] [11]

Conditions studied

Growth hormone deficiency and GH secretagogue use

Sources

Numbered citations above point to these primary sources. PubMed entries link to the indexed abstract.

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APA style: PeptideAgent. (2026, September 22). Hexarelin vs GHRP-2: evidence, cost, and legality. https://peptideagent.ai/compare/hexarelin-vs-ghrp-2
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