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Muscle & strength · Daily shot

Hexarelin

Gray market

Checked · 19 sources · 11 corrections on this page · No vendors · No affiliates · No one buys a word of it

58 human pilot studies

Limited Human Data · PubMed count · mostly single-dose 1990s · about a dozen people each

Gray market · No FDA ruling — not on any list

Sold as a research chemical. Some clinics and pharmacies still supply it; that’s their risk, not a change in the rule.

Bottom line

One IV dose released about twice the GH of the same dose of GHRH (Ghigo et al., 1994). In the 16-week trial in older adults, IGF-1, body fat, lean mass and bone density did not change (Rahim et al., 1998).

Also called
Examorelin · EP 23905 · HEX · His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH₂
Category
Peptide — GHRP (Growth Hormone-Releasing Peptide)
Molecular Weight
887.05 Da
Sequence
6 aa (hexapeptide)
Half-life
~70 min (plasma)
Route (studied)
SubQ, IV, oral, intranasal (people) · SubQ (rats)
Route (sold)
SubQ vials (research chemical)
FDA Status
Not approved; not on any FDA 503A list
Discovery
Deghenghi (Europeptides) 1991
Primary Receptors
GHSR-1a + CD36
GH Potency
~2x GHRH @ equal dose
WADA Status
Banned (S2)
Cost & Access
Research-only

Also for muscle & strength

The other four questions

What does it do? Fires a growth-hormone pulse at the pituitary (Imbimbo et al., 1994). Separately binds CD36, a receptor on heart cells (Bodart et al., 2002), and protected rat hearts from ischemia without growth hormone (Locatelli et al., 1999).
Who uses it? Research labs studying the ghrelin receptor and CD36 (Mao et al., 2014). User forums describe short courses of injections.
Does the evidence hold up? Mostly single-dose 1990s studies in about a dozen people each (Ghigo et al., 1994; Imbimbo et al., 1994). Heart-protection data come mainly from animals and cells (Mao et al., 2014). ClinicalTrials.gov lists no hexarelin trial. With twice-daily use the GH response fell by about a third within four weeks (Rahim et al., 1998), and single doses also raise cortisol and prolactin (Arvat et al., 1997).
Bottom line? One IV dose released about twice the GH of the same dose of GHRH (Ghigo et al., 1994). In the 16-week trial in older adults, IGF-1, body fat, lean mass and bone density did not change (Rahim et al., 1998).

Dosing from the Literature

Published for growth hormone: single IV doses of 0.5–2 μg/kg in healthy adults (Imbimbo et al., 1994; Ghigo et al., 1994), and 1.5 μg/kg under the skin twice a day for 16 weeks in 12 healthy older adults, whose GH response fell partly and recovered after stopping (Rahim et al., 1998). Not published: a trial of the on-and-off cycles user forums describe, or of repeated doses for the heart.

Each row names its source: a published trial, with the people it enrolled, or what user forums describe.

ProtocolDoseFrequencyNotes
Single IV dose (Ghigo 1994; Imbimbo 1994)0.5–2 μg/kg IVSingle doseTrials: 12 healthy young volunteers (Ghigo et al., 1994) and 12 healthy men (Imbimbo et al., 1994); the GH response was close to its maximum at 2 μg/kg.
Diagnostic test with GHRH (Gasperi 1999)0.25 μg/kg hexarelin + 1 μg/kg GHRH, IVSingle doseTrial: a test for adult GH deficiency, in healthy adults and 19 adults with GH deficiency (Gasperi et al., 1999).
Twice-daily course (Rahim 1998)1.5 μg/kg SubQTwice daily for 16 weeksTrial: 12 healthy older adults aged 66–81 (Rahim et al., 1998). The GH response to an injection was about a third lower by week 4 and about 45% lower by week 16, and back to its starting level four weeks after stopping; IGF-1, body fat, lean mass and bone density did not change.
SubQ short-course (community)100 μg1–2× daily, SubQWhat user forums describe, for body composition, in courses of 2–3 weeks meant to get around the fading GH response.
"Cardiac support" short-course200–300 μg/dayDivided doses, 2–3 weeks on / 2–4 weeks offWhat user forums describe, for the heart. In people, hexarelin's heart effects have been studied only as single IV doses of 2 μg/kg (Mao et al., 2014).
Pre-training dose100 μg30 min before trainingWhat user forums describe, to line the GH pulse up with exercise.
Pre-sleep dose100 μgAt bedtimeWhat user forums describe, to line it up with the night-time GH pulse. Given at night to seven healthy young men, four 50 μg doses an hour apart from 22:00 reduced deep sleep (Frieboes et al., 2004).
Combined with GHRH analog100 μg hexarelin + sermorelin or CJC-1295BedtimeWhat user forums describe. In healthy men, a low IV dose of hexarelin (0.125 μg/kg) with 1 μg/kg of GHRH(1-29), the molecule sold as sermorelin, released a large GH pulse with a moderate prolactin rise and no rise in cortisol (Massoud et al., 1996).
Cycle pattern2–3 weeks on / 2–4 weeks off—What user forums describe, to get around the fading GH response. No trial has tested a cycle; in the 16-week trial the response had fallen by week 4 (Rahim et al., 1998).
Dosing Disclaimer

Hexarelin has no approved dose for any use. In healthy men given single IV doses, GH and prolactin both reached their plateau at 1 μg/kg and cortisol rose by about 40% from 0.5 μg/kg (Massoud et al., 1996). With twice-daily use the GH response fell partly and recovered after stopping (Rahim et al., 1998). Consult a licensed healthcare provider.

→ Calculator — vial-to-syringe math

What It Is

Hexarelin (examorelin; originally EP 23905) is a synthetic hexapeptide (a chain of 6 amino acids) growth hormone secretagogue (GHRP) developed in the early 1990s by Romano Deghenghi and colleagues at Europeptides. Its amino acid sequence is His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH₂ — a modification of the earlier reference compound GHRP-6 with an additional D-2-methyltryptophan substitution at position 2. In people it releases more growth hormone than GHRH or GHRP-6 (Frieboes et al., 2004).

Hexarelin was extensively studied in the 1990s as a candidate provocative-test agent for growth hormone deficiency and as a therapeutic for adult GH replacement. Ghigo, Imbimbo, and colleagues in Italy generated most of the early clinical pharmacology, including the foundational observation that 1 μg/kg IV hexarelin produces approximately twice the peak GH response of 1 μg/kg IV GHRH (the signal that tells the pituitary to release GH) in healthy young adults (Ghigo et al., J Clin Endocrinol Metab 1994). The compound was found to be active across intravenous, subcutaneous, intranasal, and oral routes — a breadth of bioavailability unusual for a peptide.

Despite the promising clinical pharmacology, hexarelin never achieved commercial approval anywhere. With twice-daily injections for 16 weeks, its GH response fell partly and IGF-1 did not change in 12 healthy older adults (Rahim et al., 1998); on the same regimen the cortisol response to each dose fell and the prolactin response did not change (Rahim et al., 1999).

What kept hexarelin clinically and scientifically interesting well past its GH-secretagogue era was the 2002 discovery by Bodart et al. (Circulation Research; PMID 11988484) that hexarelin's binding site in the heart is the scavenger receptor CD36; in isolated rat and mouse hearts, hexarelin acting through CD36 narrowed the coronary vessels. Earlier, hexarelin had protected hearts from ischemia in rats whose pituitary had been removed, so without growth hormone (Locatelli et al., 1999), and a 2014 review traces its heart effects to both CD36 and the ghrelin receptor (Mao et al., 2014). That work is the foundation for modern interest in hexarelin as a cardioprotective peptide rather than a chronic GH secretagogue.

Hexarelin sits within a broader class of small-molecule growth-hormone secretagogues developed in the 1990s, including GHRP-2, GHRP-6, ipamorelin, and the orally active non-peptide MK-677 (ibutamoren). Hexarelin's modern research niche is almost entirely defined by the CD36 cardioprotective mechanism, not the GH-axis mechanism.

Mechanism of Action

Hexarelin acts on two receptors: GHSR-1a, the ghrelin receptor, through which it releases growth hormone, and CD36, a receptor on heart cells; in animal and cell studies its heart effects have been traced to both (Mao et al., 2014).

  • GHSR-1a agonism (GH axis) — Acts on the ghrelin receptor (Bodart et al., 2002) at both the pituitary and the hypothalamus (brain's hormonal control center) (Arvat et al., 1997). The signals proposed for this receptor include intracellular calcium, cAMP, protein kinases A and C, and phospholipase C (Chen, 2000). Potency is approximately 2× that of native GHRH at equivalent mass doses (Ghigo 1994).
  • CD36 binding (heart) — Hexarelin binds CD36, a B-type scavenger receptor expressed on cardiomyocytes and on the lining of small blood vessels; in isolated rat and mouse hearts, hexarelin acting through CD36 raised coronary perfusion pressure, narrowing the vessels, an effect absent in hearts lacking CD36 (Bodart et al., Circ Res 2002). Another GH-releasing peptide that does not bind the heart, EP 51389, did not protect rat hearts (Locatelli et al., 1999).
  • Direct cardiac effects — In isolated rat hearts, hexarelin reduced infarct size after ischemia and reperfusion; in rats with heart failure it reduced myocardial apoptosis (programmed cell death); and two weeks of injections after an experimental heart attack raised stroke volume and cardiac output in rats (Mao et al., 2014). In rat hearts after ischemia and reperfusion, it prevented the fall in prostacyclin release and improved the recovery of contractility, without growth hormone (Locatelli et al., Endocrinology 1999).
  • ACTH/cortisol elevation (off-target) — At the IV doses that release GH, hexarelin also raised ACTH and cortisol in children, young adults and older people (Arvat et al., 1997); in healthy men cortisol rose by about 40% from 0.5 μg/kg (Massoud et al., 1996). How it does so is not settled: the ACTH response grew when cortisol feedback was removed, in healthy women given metyrapone and in patients with Addison's disease (Arvat et al., 1999), and a sleep study proposed a shift toward CRH (Frieboes et al., 2004).
  • Prolactin elevation — Hexarelin raised prolactin by similar amounts in children, young adults and older people (Arvat et al., 1997); in healthy men the prolactin response reached its plateau at 1 μg/kg IV, the same dose as GH (Massoud et al., 1996).
  • Nitric oxide — In rats with atherosclerosis induced by diet and vitamin D3, hexarelin raised blood nitric oxide and aortic eNOS expression (Mao et al., 2014).
  • Tachyphylaxis — In 12 healthy older adults given 1.5 μg/kg twice a day under the skin, the GH response to an injection was about a third lower by week 4 and about 45% lower by week 16, and back to its starting level four weeks after stopping (Rahim et al., 1998).
  • Appetite stimulation — In rats, hexarelin injected into the arcuate nucleus of the hypothalamus increased food intake, an effect blocked by an NPY antagonist (Torsello et al., 2000).
  • Sleep — Ghrelin promotes slow-wave sleep, but hexarelin reduced it: in seven healthy young men given four 50 μg doses an hour apart from 22:00, deep (stage 4) sleep in the first half of the night and EEG delta power across the night fell, while GH, prolactin, ACTH and cortisol rose (Frieboes et al., 2004).
  • Synergy with GHRH — GH secretagogues act synergistically with GHRH, even at low doses (Gasperi et al., 1999); in healthy men, low-dose hexarelin (0.125 μg/kg) was synergistic with 1 μg/kg of GHRH(1-29) (Massoud et al., 1996).

What the Research Shows

Hexarelin has an unusually deep 1990s-era pharmacology database for a compound that never achieved approval. Modern interest has shifted substantially toward the cardioprotective signal.

Honest Evidence Framing

Hexarelin has abundant acute-use human pharmacology data, solid preclinical cardioprotection data, but no approved indication and no Phase 3 cardioprotection trials in humans. Over 16 weeks of twice-daily injections in older adults, the GH response fell partly while the cortisol and prolactin responses did not rise (Rahim et al., 1998; Rahim et al., 1999). User forums describe short courses, some aimed at the heart; in people, its heart effects have been studied only as single IV doses (Mao et al., 2014).

Human Data

PubMed tags 58 reports on hexarelin as clinical trials (search of October 2026). Key published human datasets:

  • Dose-response (Imbimbo 1994) — Single intravenous boluses of 0.5, 1 and 2 µg/kg in twelve healthy men. ED50 0.50 µg/kg for peak GH and 0.64 µg/kg for the 0–180 minute area under the curve.
  • GH dose-response (Ghigo 1994; PMID 8126144) — 12 healthy young volunteers; IV (1, 2 μg/kg), SC (1.5, 3 μg/kg), IN (20 μg/kg), oral (20, 40 mg). 1 μg/kg IV hexarelin produced ~2× GH response of equivalent-dose GHRH.
  • Combined GHRH + hexarelin — Synergistic GH release in healthy adults and in patients with glucocorticoid excess.
  • Age and the hormone response (Arvat 1997) — At 2.0 µg/kg intravenously, the GH and ACTH responses to hexarelin varied with age across prepubertal children, pubertal children, young adults and the elderly, while the prolactin response did not.
  • GHD diagnostic testing (Gasperi 1999; PMID 10443652) — Low-dose hexarelin + GHRH as alternative to insulin tolerance test for adult GHD diagnosis.
  • Addison's / Cushing's ACTH response (Arvat 1999; PMID 10516483) — Documented corticotropin-releasing activity of hexarelin, important for understanding the cortisol side-effect profile.
  • Hemodialysis patients (Jenkins 1999; PMID 10199757) — Dose, nutrition, and age effects on hexarelin-induced GH secretion in dialysis patients.
  • Long-term dosing tachyphylaxis — Multiple groups documented that 2–4 weeks of chronic daily dosing leads to attenuated GH response.
  • Older adults (Arvat 1997) — A single 2.0 µg/kg IV dose released about half as much GH in 16 elderly people as in 20 young adults.

What is absent: a Phase 3 chronic-use trial for any indication. Hexarelin's 1990s development program delivered thorough pharmacology but no registrational commercial pathway. Modern human cardioprotection RCTs using hexarelin specifically have not been published.

Reconstitution & Storage

Sellers list hexarelin as a freeze-dried powder in vials. The table is arithmetic for 2 mg and 5 mg vials and the 100 μg dose user forums describe.

Vial SizeBAC WaterConcentration100 μg Dose
2 mg1 mL2 mg/mL5 units (0.05 mL)
2 mg2 mL1 mg/mL10 units (0.10 mL)
5 mg2 mL2.5 mg/mL4 units (0.04 mL)
5 mg2.5 mL2 mg/mL5 units (0.05 mL)
  • Reconstitution — In a 1998 trial, each vial held 100 μg of hexarelin with 20 mg of mannitol and was mixed with 1 mL of saline just before injection (Rahim et al., 1998).
  • Storage — In the same trial, unmixed vials were kept at 2–8 °C and each dose was mixed fresh; the trial gives no shelf life once mixed (Rahim et al., 1998).

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Side Effects & Risks

Important

Single doses of hexarelin raise cortisol and prolactin (Arvat et al., 1997), and with twice-daily use its GH response fell by about a third within four weeks (Rahim et al., 1998). WADA-banned under S2. ClinicalTrials.gov lists no hexarelin trial. Consult a licensed healthcare provider.

  • Cortisol / ACTH elevation — Single IV doses raised ACTH and cortisol in children, young adults and older people (Arvat et al., 1997), cortisol by about 40% from 0.5 μg/kg in healthy men (Massoud et al., 1996). Over 16 weeks of twice-daily injections in older adults, the cortisol response to each dose fell rather than rose, and 24-hour urinary cortisol, baseline cortisol and the ACTH response did not change (Rahim et al., 1999).
  • Prolactin elevation — Single doses raised prolactin by similar amounts at every age tested (Arvat et al., 1997). After 16 weeks of twice-daily injections in older adults, the prolactin response to an injection was unchanged (Rahim et al., 1999).
  • Tachyphylaxis (GH desensitization) — In 12 healthy older adults on 1.5 μg/kg twice a day, the GH response to an injection was about a third lower by week 4 and about 45% lower by week 16; all but one still responded, and four weeks after the last dose the response was back to its starting level (Rahim et al., 1998).
  • Appetite stimulation — Shown in rats: hexarelin injected into the hypothalamus increased food intake (Torsello et al., 2000).
  • Glucose and insulin — Shown for ghrelin, not hexarelin: ghrelin, which acts on the same receptor, lowered insulin and raised blood glucose in seven healthy young volunteers (Broglio et al., 2003).
  • Sleep disturbance — Given at night to seven healthy young men, hexarelin reduced deep sleep (Frieboes et al., 2004).
  • IGF-1 — Over 16 weeks of twice-daily injections in 12 healthy older adults, IGF-1 did not change (Rahim et al., 1998).
  • WADA status — Banned under S2. Not viable for competitive athletes.
  • Heart — In people, only single IV doses have been studied: 2 μg/kg raised left ventricular ejection fraction for up to an hour in seven male volunteers, and raised it along with cardiac output in 24 men with coronary artery disease during bypass surgery (Mao et al., 2014). Evidence of heart protection comes mainly from animals and cells, and the review's authors call for clinical trials (Mao et al., 2014). Through CD36, hexarelin also narrowed the coronary vessels of isolated rat and mouse hearts (Bodart et al., 2002).
  • Drug interactions — Drugs that act on cortisol change the adrenal response: low-dose dexamethasone abolishes hexarelin's ACTH and cortisol response in healthy people, and in six healthy women metyrapone, which blocks cortisol production, enlarged its ACTH response without changing its GH response (Arvat et al., 1999).
  • Purity concerns — Sold as a research chemical, not an approved drug, so no FDA review covers its purity.

Bloodwork & Monitoring

No trial, label or guideline sets monitoring for hexarelin. In a 16-week trial in 12 healthy older adults, the researchers measured the GH response to an injection, IGF-1, IGFBP-3, bone markers, body composition and bone density (Rahim et al., 1998); a report on the same regimen measured the cortisol, ACTH and prolactin responses, 24-hour urinary free cortisol and thyroid hormones (Rahim et al., 1999).

Commonly Stacked With

Sermorelin

User forums describe the pairing. Studied together only as IV doses in a lab: in healthy men, low-dose hexarelin (0.125 μg/kg) with 1 μg/kg of GHRH(1-29), the molecule sold as sermorelin, released a large GH pulse with a moderate prolactin rise and no rise in cortisol (Massoud et al., 1996).

Tested together in people: 3 small human studies (1996) (Massoud et al., Clin Endocrinol 1996; Massoud et al., J Clin Endocrinol Metab 1996; Giustina et al., 1996) · Read the receipt →

CJC-1295 (no DAC)

User forums describe pairing it with CJC-1295 (no DAC) in short courses. No study has tested the two together.

Tested together in people: none published · Read the receipt →

Stacking this? Read the receipt →

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Legal Status

Current Status — April 2026

Hexarelin is not approved by the FDA for any indication. Despite an extensive 1990s clinical development program, it never achieved commercial approval. It is not listed by the FDA as a Category 2 Bulk Drug Substance or in any other 503A category, and is ineligible for compounding pharmacy use under 503A / 503B.

Hexarelin was not among the 12 peptides FDA removed from Category 2 in April 2026, and FDA’s 503A categories list, updated May 14, 2026, does not name it (FDA 503A categories list, April 22 and May 14, 2026); compounding it remains prohibited.

Hexarelin is banned by WADA under S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics) as a named GH secretagogue.

Gray-market "research use only" hexarelin is the primary availability route. Pharmacy-compounded hexarelin is not legally available under current FDA enforcement.

Cost & Access

Hexarelin is not approved for human use in the United States. It is available through research suppliers for laboratory research purposes only.

U.S. compounding pharmacies cannot legally compound hexarelin under current FDA bulk-substance rules. Online research-chemical channels list hexarelin at varying price points, in 5 mg or 10 mg vials; at the 100 mcg once or twice a day that user forums describe, a month comes to 3–6 mg.

Hexarelin is not on any FDA 503A bulk-substance list.

Estimated access context as of April 2026. Actual availability and costs vary by provider, location, and prescription status. Kalios does not sell compounds.

References

  1. Ghigo E, Arvat E, Gianotti L, Imbimbo BP, Lenaerts V, Deghenghi R, Camanni F. Growth hormone-releasing activity of hexarelin, a new synthetic hexapeptide, after intravenous, subcutaneous, intranasal, and oral administration in man. J Clin Endocrinol Metab. 1994;78(3):693-698. PMID: 8126144.
  2. Imbimbo BP, Mant T, Edwards M, Amin D, Dalton N, Boutignon F, Lenaerts V, Wüthrich P, Deghenghi R. Growth hormone-releasing activity of hexarelin in humans. A dose-response study. Eur J Clin Pharmacol. 1994;46(5):421-425. PMID: 7957536.
  3. Bodart V, Febbraio M, Demers A, McNicoll N, Pohankova P, Perreault A, Sejlitz T, Escher E, Silverstein RL, Lamontagne D, Ong H. CD36 mediates the cardiovascular action of growth hormone-releasing peptides in the heart. Circ Res. 2002;90(8):844-849. PMID: 11988484.
  4. Demers A, McNicoll N, Febbraio M, Servant M, Marleau S, Silverstein R, Ong H. Identification of the growth hormone-releasing peptide binding site in CD36: a photoaffinity cross-linking study. Biochem J. 2004;382(Pt 2):417-424. PMID: 15176951.
  5. Gasperi M, Aimaretti G, Scarcello G, et al. Low dose hexarelin and growth hormone (GH)-releasing hormone as a diagnostic tool for the diagnosis of GH deficiency in adults: comparison with insulin-induced hypoglycemia test. J Clin Endocrinol Metab. 1999;84(12):4374-4379. PMID: 10443652.
  6. Arvat E, Ramunni J, Maccagno B, Giordano R, Broglio F, Deghenghi R, Boscaro M, Ghigo E. Corticotropin-releasing effect of hexarelin, a peptidyl GH secretagogue, in normal subjects pretreated with metyrapone or RU-486, a glucocorticoid receptor antagonist. Neuroendocrinology. 1999;70(3):200-206. PMID: 10516483.
  7. Jenkins RC, El Nahas AM, Wilkie ME, Brown CB, Jones J, Ghigo E, Ross RJ. The effects of dose, nutrition, and age on hexarelin-induced anterior pituitary hormone secretion in adult patients on maintenance hemodialysis. J Clin Endocrinol Metab. 1999;84(4):1220-1225. PMID: 10199757.
  8. Locatelli V, Rossoni G, Schweiger F, Torsello A, De Gennaro Colonna V, Bernareggi M, Deghenghi R, Müller EE, Berti F. Growth hormone-independent cardioprotective effects of hexarelin in the rat. Endocrinology. 1999;140(9):4024-4031. PMID: 10465272.
  9. Mao Y, Tokudome T, Kishimoto I. The cardiovascular action of hexarelin. J Geriatr Cardiol. 2014;11(3):253-258. PMCID: PMC4178518.
  10. Arvat E, Ramunni J, Bellone J, Di Vito L, Baffoni C, Broglio F, Deghenghi R, Bartolotta E, Ghigo E. The GH, prolactin, ACTH and cortisol responses to Hexarelin, a synthetic hexapeptide, undergo different age-related variations. Eur J Endocrinol. 1997;137(6):635-642. PMID: 9437229.
  11. Rahim A, O'Neill PA, Shalet SM. The effect of chronic hexarelin administration on the pituitary-adrenal axis and prolactin. Clin Endocrinol (Oxf). 1999;50(2):233-240. PMID: 10341859.
  12. Frieboes RM, Antonijevic IA, Held K, Murck H, Pollmächer T, Schuld A, Steiger A. Hexarelin decreases slow-wave sleep and stimulates the secretion of GH, ACTH, cortisol and prolactin during sleep in healthy volunteers. Psychoneuroendocrinology. 2004;29(6):728-739. PMID: 15177700.
  13. Broglio F, Gottero C, Benso A, Prodam F, Destefanis S, Gauna C, Maccario M, Deghenghi R, van der Lely AJ, Ghigo E. Effects of ghrelin on the insulin and glycemic responses to glucose, arginine, or free fatty acids load in humans. J Clin Endocrinol Metab. 2003;88(9):4268-4272. PMID: 12970297.
  14. Torsello A, Locatelli V, Melis MR, Succu S, Spano MS, Deghenghi R, Müller EE, Argiolas A. Differential orexigenic effects of hexarelin and its analogs in the rat hypothalamus: indication for multiple growth hormone secretagogue receptor subtypes. Neuroendocrinology. 2000;72(6):327-332. PMID: 11146415.
  15. Chen C. Growth hormone secretagogue actions on the pituitary gland: multiple receptors for multiple ligands? Clin Exp Pharmacol Physiol. 2000;27(5-6):323-329. PMID: 10831231.
  16. WADA. 2026 Prohibited List. Section S2 — Peptide hormones, growth factors, related substances and mimetics. World Anti-Doping Agency.
  17. FDA. Bulk Drug Substances Nominated for Use in Compounding Under Section 503A of the FD&C Act (503A categories list), versions updated April 15, April 22 and May 14, 2026. fda.gov/media/94155/download. Read October 3, 2026. (Notice that 12 peptides would leave Category 2 because their nominations were withdrawn; their removal; GHK-Cu, except injectable, back in Category 1.)
  18. Rahim A, O'Neill PA, Shalet SM. Growth hormone status during long-term hexarelin therapy. J Clin Endocrinol Metab. 1998;83(5):1644-1649. PMID: 9589671.
  19. Massoud AF, Hindmarsh PC, Brook CG. Hexarelin-induced growth hormone, cortisol, and prolactin release: a dose-response study. J Clin Endocrinol Metab. 1996;81(12):4338-4341. PMID: 8954038.

Also for muscle & strength

Tested together in people

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Checked 18 Oct 2026