--- title: "Hexarelin: Benefits, Dosage, Side Effects & Heart" description: "Hexarelin explained: a potent ghrelin-receptor peptide that releases growth hormone, how it acts on the heart, what it is studied for, and its side effects." canonical: "https://www.vitalsvault.com/peptides/hexarelin" last-updated: 2026-08-22 --- # Hexarelin: Benefits, Dosage, Side Effects & Heart > Hexarelin explained: a potent ghrelin-receptor peptide that releases growth hormone, how it acts on the heart, what it is studied for, and its side effects. ![A white woman, 52, short spiky grey hair, wiry runner's build, freckled forearms, stands at the top of stone steps of an outdoor amphitheater on a…](https://www.vitalsvault.com/_next/image?url=%2Fpublic-v3%2Fshoot%2Fpeptides%2Fpep-hexarelin.webp&w=3840&q=75&dpl=shadow-production-f0162cb4d465-40992538108-1) Peptide Guide · Growth hormone and muscle # Hexarelin Examorelin Hexarelin is one of the strongest growth hormone-releasing peptides. Its stranger talent is that the heart responds to it even when the pituitary barely does. [Get early access to peptide care](https://www.vitalsvault.com/peptides-waitlist)[Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans) Free to join · One email when peptide care opens · Most lab results in 3–5 business days Studied forGrowth hormone release and short-term heart pumping function EvidenceEarly human data Taken asAs prescribed by a clinician Studied forGrowth hormone release and short-term heart pumping function EvidenceEarly human data Taken asAs prescribed by a clinician ## Hexarelin, in short Hexarelin is a synthetic six-amino-acid peptide that activates the ghrelin receptor (GHS-R1a) and releases a large pulse of growth hormone, more than GHRP-6 in published comparisons. It is also studied for short-term effects on heart pumping that appear independent of growth hormone, possibly through a second receptor, CD36. It raises prolactin and cortisol, and its effect fades with continuous use. Medically reviewed by [Robert Lufkin, MD (opens in a new tab)](https://www.robertlufkinmd.com/) Chief Medical Officer, Vitals Vault · Updated October 29, 2026 · 15 sources ## At a glance Early human data TypeSynthetic peptide, six amino acids[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) TargetGhrelin receptor (GHS-R1a) in the pituitary and hypothalamus; heart research also points to CD36[1](https://www.vitalsvault.com/peptides/hexarelin#source-howard-1996)[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) Studied forGrowth hormone release and acute heart pumping function[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) Other effectsRaises prolactin, ACTH and cortisol[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) LimitThe growth hormone response weakens with prolonged use and returned to about its starting level after a break[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) FDA statusNot approved. Not covered by FDA’s October 2026 enforcement discretion[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) SportGrowth hormone secretagogues are prohibited by WADA[15](https://www.vitalsvault.com/peptides/hexarelin#source-wada) ## Before you consider Hexarelin - Safety Short studies reported no side effects, but hexarelin raised stress hormones and cut deep sleep. Long-term safety has not been studied in controlled trials.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004)[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) [Side effects and safety](https://www.vitalsvault.com/peptides/hexarelin#safety) - Legal status Not FDA approved. The October 2026 policy for 503A pharmacies covers six named peptides, and hexarelin is not one of them.[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) [FDA status](https://www.vitalsvault.com/peptides/hexarelin#fda-status) - How it’s taken Research used injections into a vein or under the skin, nasal sprays and oral doses. The October 2026 policy gives no pharmacy route for hexarelin.[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) [Forms and dosage](https://www.vitalsvault.com/peptides/hexarelin#how-taken) ## How does Hexarelin work? Hexarelin signals the body to release growth hormone, and in studies it also reached the heart. - ### Triggers growth hormone It uses the signal of ghrelin, a hunger hormone, and set off a large growth hormone pulse, stronger than GHRP-6 in comparisons.[1](https://www.vitalsvault.com/peptides/hexarelin#source-howard-1996)[2](https://www.vitalsvault.com/peptides/hexarelin#source-kojima-1999)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) - ### Reached the heart A single dose raised how much blood the heart pushed out, even in men who made almost no growth hormone.[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) - ### Also nudges stress hormones In people it also raised prolactin and the stress hormones ACTH and cortisol, along with growth hormone.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) ## Hexarelin benefits: what it is studied for Hexarelin has no approved use. Everything below comes from small, short experiments in people. 1. Human study01 ### A strong growth hormone trigger In healthy young adults hexarelin produced a strong growth hormone response, higher than GHRH at the doses compared. In older adults it kept working.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) 2. Human study02 ### Short-term heart pumping function One intravenous dose raised the share of blood the heart pumps out, in men with and without growth hormone deficiency. In 24 bypass patients, cardiac output rose for up to 90 minutes.[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) 3. Human study03 ### Repeated dosing in older adults Short intermittent courses by nose or mouth did not blunt the response in older adults, and no side effects were reported in those small studies.[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) ## What the research shows Early human data 1. 1 · Cells in a labNot cited This guide cites no findings at this level. Shows a mechanism 2. 2 · Animals Studied In isolated rodent hearts, hexarelin tightened the heart’s own arteries.[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) Shows an effect in a body 3. 3 · People Studied Small, short studies show a large growth hormone rise and a brief boost in heart pumping. No study shows a clinical benefit from long-term use.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) Shows it works in people Hexarelin human studies are small and short. Over 16 weeks of repeated injections in older adults, the growth hormone response fell by close to half, then returned to about its starting level after a four-week break. No study cited here shows a clinical benefit from long-term use.[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) The full guide to Hexarelin 9 min read · Medically reviewed by Robert Lufkin, MD ## How hexarelin earned a place in heart research In Turin in the late 1990s, researchers gave a single intravenous dose of hexarelin to seven men whose pituitaries could barely make growth hormone. As expected, their growth hormone hardly moved, peaking at about a twenty-fifth of what healthy men produced. Their hearts told a different story. The share of blood the left ventricle pushed out with each beat rose, just as it did in the healthy men. That result captures what makes hexarelin unusual. It belongs to the GHRP family and is a synthetic six-amino-acid analog of GHRP-6, and Turin endocrinologists describe it and GHRP-2 as synthetic super-analogs of GHRP-6. Its chain, His-D-2-methylTrp-Ala-Trp-D-Phe-Lys-NH2, differs from GHRP-6 by a single modified tryptophan, and that small change makes it one of the strongest members of the family. At its main job it is formidable. In healthy young adults, hexarelin and GHRP-2 released similar, strong amounts of growth hormone, more than GHRH did at the doses compared. Munich sleep researchers describe hexarelin as superior to both GHRH and GHRP-6 at stimulating growth hormone release. So hexarelin carries two stories. One is the familiar growth hormone story, with its fading response and stress-hormone side effects. The other is a heart story that does not seem to depend on growth hormone at all, and it is the reason this peptide keeps turning up in cardiology journals.[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) ## How hexarelin works: the ghrelin receptor and beyond Hexarelin’s growth hormone effect runs through the growth hormone secretagogue receptor, GHS-R1a, on pituitary cells and in the hypothalamus. A Merck team cloned that receptor in 1996, and in 1999 Japanese researchers found its natural partner, ghrelin, a hunger and growth hormone signal made in the stomach. Like the rest of its family, hexarelin seems to work by easing somatostatin, the brake on growth hormone, and by adding to GHRH, the body’s own releasing hormone. A 1997 review notes that the two act synergistically, and that GHRPs keep working in many conditions where inhibitory signals almost abolish the response to GHRH. The receptor does not stop at growth hormone. In a 1997 Turin study of six young adults, hexarelin also raised prolactin, ACTH and cortisol. The prolactin effect was smaller than that of TRH, a strong prolactin releaser, but the ACTH and cortisol effect matched corticotropin-releasing hormone, the usual starter of the stress axis. Then there is the heart. Researchers describe GHRPs as having specific receptors in the pituitary, the hypothalamus and heart muscle, and a 2002 Montreal study identified one of the heart’s binding sites for hexarelin as a protein called CD36. CD36 is a candidate for some of hexarelin’s heart effects, though its role in the human pumping results is unproven.[1](https://www.vitalsvault.com/peptides/hexarelin#source-howard-1996)[2](https://www.vitalsvault.com/peptides/hexarelin#source-kojima-1999)[9](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1997)[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) ## Hexarelin benefits studied in older adults Growth hormone output falls with age, yet a 1996 Turin paper points out that the pituitary cells that make it keep their capacity. That raised an obvious question. Could a strong secretagogue wake up an ageing system, and would it keep working if given repeatedly? The team ran two small studies. Seven adults aged 67 to 80 took hexarelin by nasal spray for 8 days, and seven women aged 63 to 80 took it by mouth for 15 days. Neither course blunted the growth hormone response. After the nasal course IGF-1 did not change but its binding protein IGFBP-3 rose, and after the oral course both IGF-1 and IGFBP-3 rose slightly but significantly. Neither route changed prolactin or cortisol over the course, and the researchers saw no side effects. The authors suggested that longer treatment might restore the reduced growth hormone release of ageing. With 14 people and 15 days at most, that is a hypothesis to test, and the next study tested it.[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) ## Does hexarelin stop working? What 16 weeks showed Manchester endocrinologists framed the stakes plainly. If the growth hormone response to hexarelin faded with long-term use, that would seriously limit its usefulness. They gave 12 healthy older adults repeated hexarelin injections for 16 weeks and measured the growth hormone response along the way. It faded. Total growth hormone released after a test dose fell by about a third in the first week, stayed lower at week 4, and by week 16 was about 45 percent below where it started. Then the team stopped for four weeks and tested again. The response was back to its starting level. The authors called the attenuation partial and reversible, and that fits the earlier findings. Short, intermittent courses in the Turin studies did not blunt the response, and a 1997 review describes more desensitization with continuous exposure and less with intermittent use. The pituitary appears to keep count, so the pattern and duration of exposure can shape how much the response fades.[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996)[9](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1997) ## Hexarelin and the heart: what the human studies showed The 1999 Turin study compared seven men with growth hormone deficiency, average age 42, with nine healthy men. At baseline the deficient men had weaker hearts, with an ejection fraction of 50 percent against 63 percent. After one dose of hexarelin it rose to 57 percent in the patients and 70 percent in the controls, without changes in adrenaline-type hormones, blood pressure or cardiac output. In 2002 the same group took the question into the operating room. Twenty-four men with coronary artery disease, under general anesthesia for bypass surgery, received hexarelin, GHRH, growth hormone itself or placebo. Only hexarelin moved the heart. Within 10 minutes ejection fraction, cardiac index and cardiac output rose, lasting up to 90 minutes, while the pressure in the lung circulation fell and heart rate stayed the same as on placebo. The control groups are what make this convincing. Hexarelin raised growth hormone only slightly, about as much as GHRH did and far less than injected growth hormone, and neither of those had any effect on the heart. The authors concluded the heart effect does not come from circulating growth hormone and more likely reflects receptors in the cardiovascular system. These were single doses, measured for minutes to hours, in a few dozen people. They show an acute effect on pumping. They do not show what repeated hexarelin does to a heart over months.[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) ## A second receptor, and why it cuts both ways In 2002, a Montreal team went looking for the heart’s hexarelin receptor. They tagged a version of hexarelin so it would lock onto whatever it touched in rat heart membranes, then purified the catch. The protein turned out to be CD36, a multipurpose receptor found on heart muscle cells and on the cells lining small blood vessels. What CD36 did next was a surprise. In isolated, perfused rodent hearts, hexarelin acting on CD36 raised coronary perfusion pressure in a dose-dependent way, meaning the heart’s own arteries tightened. Hearts from mice lacking CD36, and from a rat strain born without it, showed no such response. The authors suggested CD36 may help explain the coronary artery spasm seen with high cholesterol and atherosclerosis. Other researchers emphasize a different side of the same receptor. A 2017 review argues that GHRPs bind both the ghrelin receptor and CD36, and that CD36 binding switches on survival pathways that protect heart cells in animal models. Put those findings side by side. Hexarelin’s heart effects appear to run largely outside growth hormone, and the receptor behind them has been linked both to stronger pumping and cell protection and to narrower coronary arteries. Whether CD36 explains the human pumping results has not been proven, and which effect wins in a person with heart disease over months has never been tested. That is a hypothesis, and an important one for anyone with a heart condition.[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002)[11](https://www.vitalsvault.com/peptides/hexarelin#source-berlanga-2017)[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) ## Hexarelin and sleep: less deep sleep, more cortisol A 2004 Munich study gave seven young volunteers hexarelin or placebo in repeated doses across the late evening and recorded their sleep. On hexarelin, stage 4 sleep, the deepest stage, fell in the first half of the night, and the electrical signature of deep sleep was lower across the whole night. The hormones moved at the same time. Growth hormone and prolactin stayed higher all night, and ACTH and cortisol rose in the first half. Leptin and the inflammatory signal TNF-alpha did not change, and the researchers saw no hint of an effect on the immune system. That is the reverse of what ghrelin itself does, since ghrelin, like GHRH, promotes slow-wave sleep. The authors’ hypothesis is that hexarelin tips the balance between GHRH and CRH, the stress-axis starter, toward CRH. There is an irony in it, because the largest natural growth hormone pulse of the day arrives in early deep sleep.[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) Know your baseline before any peptide 120+ lab tests at Quest Diagnostics, every result reviewed by a licensed clinician. Most results in 3–5 business days. A baseline today gives your clinician something to compare against if you start Hexarelin later. [Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans)[Get early access to peptide care](https://www.vitalsvault.com/peptides-waitlist) Full refund before your blood draw · No membership ## What we actually know about hexarelin in people Every human hexarelin study cited here is small. The largest heart study had 24 patients, the longest growth hormone study gave hexarelin to 12 older adults for 16 weeks and retested them four weeks later, and the others involved small groups in single sessions, one overnight sleep study or courses of up to 15 days. Within those limits, the findings are consistent. Hexarelin releases a lot of growth hormone, it raises prolactin, ACTH and cortisol, its effect fades with continuous use and recovers with a break, it thins deep sleep, and a single dose briefly strengthens heart pumping in a way growth hormone does not. The studies cited here do not show that hexarelin improves muscle, recovery, heart failure or ageing over the long term, and they do not establish long-term safety.[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004)[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) ## Hexarelin side effects and safety The short-term effects are well described. Hexarelin raises prolactin, ACTH and cortisol and reduces deep sleep in the hours after dosing, and its growth hormone effect partly fades with continuous use. Brief intermittent courses in older adults produced no reported side effects and did not change prolactin or cortisol over the course. The open questions are long-term and cardiac. The heart studies were single-dose experiments, and in isolated rodent hearts hexarelin tightened coronary arteries through CD36. A related ghrelin mimetic, ibutamoren (MK-677), was linked to a heart failure signal in older hip fracture patients, a concern FDA’s compounding page cites for that drug. Anyone with heart disease, diabetes or prediabetes, a personal history of cancer, a pregnancy or a place in tested sport should take hexarelin to a clinician as a question first.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996)[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002)[13](https://www.vitalsvault.com/peptides/hexarelin#source-fda-bulks) ## Which labs matter with hexarelin, and why No validated hexarelin monitoring panel exists. Hexarelin acutely raises ACTH and cortisol, and sleep disruption and chronic stress can shift cortisol too, so a single morning value has limited meaning on its own. It is baseline context for a clinician, not a test of whether hexarelin would be safe. Fasting glucose, fasting insulin and HbA1c describe general metabolic health. Growth hormone makes tissues less responsive to insulin, so that health sets the context for any growth hormone rise, and HbA1c shows the three-month average behind a single reading. This is how Vitals Vault approaches anything in the growth hormone family. A blood panel at Quest Diagnostics comes first, a licensed clinician reviews your results and history and decides what, if anything, fits, and any course ends with a retest of the same markers.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) ## Where hexarelin stands in 2026 Hexarelin is not an FDA-approved drug. The enforcement discretion FDA granted on October 29, 2026 lets 503A pharmacies compound six named peptides with a prescription, and hexarelin is not one of them. In sport, growth hormone secretagogues and releasing factors fall in the S2 class of the World Anti-Doping Agency’s Prohibited List, which applies in and out of competition. Products sold online for research use only are not made for people and fall outside FDA’s policy.[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa)[15](https://www.vitalsvault.com/peptides/hexarelin#source-wada) ## What this means for you Hexarelin is a strong ghrelin-receptor peptide with an unusual second life in heart research. It releases a lot of growth hormone, brings prolactin and cortisol along, thins deep sleep, and fades with continuous use. In single-dose studies it briefly made hearts pump harder, apparently through cardiovascular mechanisms independent of the acute rise in circulating growth hormone. That puts your heart at the top of the list. If you are curious about hexarelin, the question worth asking a clinician is what a peptide linked to stronger pumping in small human studies, and to tighter coronary arteries in isolated rodent hearts through CD36, would do in your heart, given your history and your labs.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002)[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) Know your baseline before any peptide 120+ lab tests at Quest Diagnostics, every result reviewed by a licensed clinician. Most results in 3–5 business days. A baseline today gives your clinician something to compare against if you start Hexarelin later. [Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans)[Get early access to peptide care](https://www.vitalsvault.com/peptides-waitlist) Full refund before your blood draw · No membership ## What to expect with Hexarelin A responsible start is a health history, including your heart, a baseline blood panel and a clinician’s view on whether anything in the growth hormone family fits. Hexarelin is not part of the October 2026 compounding pathway, so for most people that conversation is about understanding the trade-offs. On timing, the studies describe fast effects. Heart pumping rose within 10 minutes of a single dose and lasted up to 90 minutes. With prolonged use, the growth hormone response faded over weeks and recovered after a four-week break. No study tracked body composition or heart health over months, so any longer timeline is unknown.[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) ## Key Hexarelin studies - Arvat et al., 1997[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) Comparison study · 6 young adults, plus 6 older adults for growth hormone Strong growth hormone release, similar to GHRP-2 and above GHRH; ACTH and cortisol rise similar to CRH Limits: Tiny groups, single doses - Ghigo et al., 1996[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) Two short open studies · 14 adults aged 63 to 80 Nasal or oral courses of 8 to 15 days did not blunt the response; IGF-1 and IGFBP-3 rose slightly on the oral course Limits: Very small, 15 days at most - Rahim and Shalet, 1998[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) 16-week dosing study · 12 healthy older adults Growth hormone response about 45 percent lower by week 16; recovered after a 4-week break Limits: Small; the abstract describes no placebo comparison - Bisi et al., 1999[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999) Single-dose heart imaging study · 7 men with growth hormone deficiency, 9 healthy men Ejection fraction rose in both groups despite almost no growth hormone rise in patients Limits: One dose, short-lasting effect - Broglio et al., 2002[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) Comparison with GHRH, growth hormone and placebo · 24 men having bypass surgery Only hexarelin raised ejection fraction and cardiac output, for up to 90 minutes Limits: Under anesthesia, single dose - Bodart et al., 2002[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) Lab study · Rat and mouse hearts CD36 identified as a heart binding site for hexarelin; activation tightened coronary arteries Limits: Isolated rodent hearts Key studies on Hexarelin | Study | Design | Who | What it found | Limits | | --- | --- | --- | --- | --- | | Arvat et al., 1997[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) | Comparison study | 6 young adults, plus 6 older adults for growth hormone | Strong growth hormone release, similar to GHRP-2 and above GHRH; ACTH and cortisol rise similar to CRH | Tiny groups, single doses | | Ghigo et al., 1996[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) | Two short open studies | 14 adults aged 63 to 80 | Nasal or oral courses of 8 to 15 days did not blunt the response; IGF-1 and IGFBP-3 rose slightly on the oral course | Very small, 15 days at most | | Rahim and Shalet, 1998[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) | 16-week dosing study | 12 healthy older adults | Growth hormone response about 45 percent lower by week 16; recovered after a 4-week break | Small; the abstract describes no placebo comparison | | Bisi et al., 1999[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999) | Single-dose heart imaging study | 7 men with growth hormone deficiency, 9 healthy men | Ejection fraction rose in both groups despite almost no growth hormone rise in patients | One dose, short-lasting effect | | Broglio et al., 2002[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) | Comparison with GHRH, growth hormone and placebo | 24 men having bypass surgery | Only hexarelin raised ejection fraction and cardiac output, for up to 90 minutes | Under anesthesia, single dose | | Bodart et al., 2002[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) | Lab study | Rat and mouse hearts | CD36 identified as a heart binding site for hexarelin; activation tightened coronary arteries | Isolated rodent hearts | ## Hexarelin myths and evidence - ### Hexarelin keeps working the same way no matter how long you use it In 12 older adults given repeated injections, the growth hormone response fell about 45 percent over 16 weeks. It returned to about its starting level after a four-week break.[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) - ### Hexarelin helps the heart by raising growth hormone The heart effect appeared in men who barely made growth hormone, and in bypass patients neither growth hormone nor GHRH changed heart function. The effect seems to run through cardiovascular mechanisms instead.[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999)[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) - ### Hexarelin deepens sleep the way ghrelin and GHRH do In a sleep-lab study it did the opposite. Deep sleep fell in the first half of the night, and ACTH and cortisol rose.[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) - ### The strongest growth hormone peptide gives the best results Hexarelin is among the strongest at releasing growth hormone, but no controlled trial shows better muscle, recovery or ageing outcomes, and it can also raise cortisol and prolactin.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004) Know your baseline first 120+ lab tests at Quest, every result reviewed by a licensed clinician. Most results in 3–5 business days. [Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans) ## How is Hexarelin taken? Research has used intravenous doses, subcutaneous injections, intranasal sprays and oral doses. Products sold online for research use only are not made for people, and there is no pharmacy pathway for hexarelin under the October 2026 policy.[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998)[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) ## Hexarelin dosage There is no FDA-approved dose of hexarelin for any use. Studies in people mostly gave single test injections into a vein, dosed by body weight. The longest study gave injections under the skin twice a day for 16 weeks in older adults, and short studies in older adults tested fixed amounts given into the nose or by mouth. Your clinician sets your dose, if any.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997)[6](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1999)[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) ## Typical Hexarelin dosage Hexarelin has only been studied in people in small, short trials. The injection studies set doses by body weight: most gave a single test injection into a vein, and the longest course was an injection under the skin twice a day for 16 weeks in healthy older adults. Short studies gave fixed amounts into the nose or by mouth, with approximate weight equivalents shown in the table. There is no approved dose, and a clinician sets any actual dose. These are reference doses from FDA labels, studies in people and clinical practice reports, shown for education. They are not a recommendation or a prescription. Your dose, form and schedule should be set by a licensed clinician who knows your history and lab results. Already have a prescribed dose? The [peptide dosage calculator](https://www.vitalsvault.com/peptides/tools/dosage-calculator) turns it into the units to draw on an insulin syringe. - Human trial · Injection into a vein 1 or 2 µg/kg (young adults); 2 µg/kg (older adults) Single test dose[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) Healthy young adults aged 22 to 27 received both doses; healthy older adults aged 66 to 73 received 2 µg/kg only. Growth hormone testing - Human trial · Injection under the skin 1.5 µg/kg Twice daily[6](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1999)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) Healthy older adults, for 16 weeks; the growth hormone response partly faded - Human trial · Into the nose (intranasal) 1.25 mg (about 18 µg/kg) Three times daily[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) Seven adults aged 67 to 80, for 8 days - Human trial · By mouth 20 mg (about 300 µg/kg) Three times daily[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) Seven women aged 63 to 80, for 15 days Typical Hexarelin doses in people, by source | Source | Form | Amount | How often | Notes | | --- | --- | --- | --- | --- | | Human trial[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) | Injection into a vein | 1 or 2 µg/kg (young adults); 2 µg/kg (older adults) | Single test dose | Healthy young adults aged 22 to 27 received both doses; healthy older adults aged 66 to 73 received 2 µg/kg only. Growth hormone testing | | Human trial[6](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1999)[5](https://www.vitalsvault.com/peptides/hexarelin#source-rahim-1998) | Injection under the skin | 1.5 µg/kg | Twice daily | Healthy older adults, for 16 weeks; the growth hormone response partly faded | | Human trial[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) | Into the nose (intranasal) | 1.25 mg (about 18 µg/kg) | Three times daily | Seven adults aged 67 to 80, for 8 days | | Human trial[4](https://www.vitalsvault.com/peptides/hexarelin#source-ghigo-1996) | By mouth | 20 mg (about 300 µg/kg) | Three times daily | Seven women aged 63 to 80, for 15 days | ## Is Hexarelin right for you? A clinician makes the call. These are the questions they will ask first. ### It may suit - Adults curious about growth hormone biology who want a clinician to review their labs first - People who want to compare hexarelin, GHRP-2 and newer secretagogues before deciding anything - Anyone who wants glucose, insulin and cortisol measured before and after ### Talk to a clinician first if you are - Heart disease, heart failure or taking heart medicines - Diabetes, prediabetes or insulin resistance - A personal or family history of cancer (growth hormone and IGF-1 promote cell growth) - Pregnant or breastfeeding - Tested athletes (WADA prohibits growth hormone secretagogues) Vitals Vault peptide care starts with a blood panel and a licensed clinician, and ends with a retest. [Get early access to peptide care](https://www.vitalsvault.com/peptides-waitlist) ## Hexarelin vs GHRP-2 Hexarelin vs GHRP-2 | Attribute | Hexarelin | GHRP-2 | | --- | --- | --- | | Growth hormone release | Strong, similar to GHRP-2 | Strong, similar to hexarelin | | Prolactin, ACTH, cortisol | Raised | Raised | | Heart studies | Raised ejection fraction in small studies | Not a focus of the studies cited | | On FDA’s safety page | No | Yes, injectable and nasal, 503B | ## The ghrelin receptor reaches well beyond the pituitary One peptide moved growth hormone, cortisol and heart output in the same studies, and the heart effect did not track the growth hormone response. That is why hexarelin is hard to read as only a growth hormone drug. Sleep and the stress axis matter most here, because in one sleep-lab study hexarelin reduced deep sleep while raising cortisol.[12](https://www.vitalsvault.com/peptides/hexarelin#source-frieboes-2004)[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999) ### What else moves the same system 1. 01Deep sleepThe largest natural growth hormone pulse comes in early deep sleep, the stage hexarelin reduced in one study. 2. 02Stress and cortisolStress and sleep disruption shift cortisol, the same hormone hexarelin pushes up in the short term. 3. 03Resistance trainingHeavy lifting is a strong natural trigger for growth hormone release. 4. 04Glucose and insulinMetabolic health sets the context for any growth hormone rise, so fasting glucose and insulin are worth knowing. ## Labs to check with Hexarelin A blood test before you start and a retest after shows what actually changed for you. It is how Vitals Vault approaches every treatment. 1. TestA baseline panel at Quest Diagnostics. 2. DecideA licensed clinician reviews your history and results. 3. RetestThe same markers again, side by side. [Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans) - [Fasting glucoseA simple metabolic marker to retest.](https://www.vitalsvault.com/biomarkers/glucose) - [Fasting insulinShows insulin resistance earlier than glucose alone.](https://www.vitalsvault.com/biomarkers/insulin) - [HbA1cYour average blood sugar over about three months.](https://www.vitalsvault.com/biomarkers/hemoglobin-a1c) - [CortisolHexarelin acutely raises cortisol, so a clinician may want a baseline for context. One value does not measure stress on its own.](https://www.vitalsvault.com/biomarkers/cortisol-total) ## Is Hexarelin FDA approved? No. Hexarelin is not an FDA-approved drug. The October 29, 2026 enforcement discretion covers six named peptides, and hexarelin is not one of them. Sellers that offer it as a medicine are outside FDA’s policy.[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) ### Hexarelin timeline 1. 1996 A Merck team clones the pituitary and hypothalamic receptor that hexarelin and its relatives act on.[1](https://www.vitalsvault.com/peptides/hexarelin#source-howard-1996) 2. 1997 Hexarelin and GHRP-2 are compared in healthy adults and found to release similar, strong amounts of growth hormone, with some prolactin, ACTH and cortisol.[3](https://www.vitalsvault.com/peptides/hexarelin#source-arvat-1997) 3. 1999 Hexarelin raises left ventricular ejection fraction in adults with growth hormone deficiency.[7](https://www.vitalsvault.com/peptides/hexarelin#source-bisi-1999) 4. 2002 Montreal researchers identify CD36 as a hexarelin binding protein in the heart.[10](https://www.vitalsvault.com/peptides/hexarelin#source-bodart-2002) 5. 2002 Hexarelin improves cardiac index and output in patients having bypass surgery.[8](https://www.vitalsvault.com/peptides/hexarelin#source-broglio-2002) 6. October 29, 2026 FDA grants enforcement discretion for six named peptides. Hexarelin is not among them.[14](https://www.vitalsvault.com/peptides/hexarelin#source-ncpa) ![A Black woman, 69, petite, white cropped curls, pearl studs reads in a garden chair](https://www.vitalsvault.com/_next/image?url=%2Fpublic-v3%2Fshoot%2Fpeptides%2Ffaq-hexarelin.webp&w=3840&q=75&dpl=shadow-production-f0162cb4d465-40992538108-1) ## Hexarelin questions What is hexarelin used for? Hexarelin is studied for growth hormone release and for short-term effects on how well the heart pumps. People ask about it for muscle and recovery, but no controlled trials show those benefits. It is not FDA-approved for any use. What are the benefits of hexarelin? The documented effects are a strong growth hormone rise and a short-lasting increase in left ventricular ejection fraction in small human studies. Long-term benefits for muscle, fat loss or ageing have not been shown. How does hexarelin work? It activates the ghrelin receptor, which sits on pituitary cells and also in the heart. In the pituitary it triggers growth hormone release. In heart studies its effect appeared independent of the growth hormone rise. What are the side effects of hexarelin? Studies show higher prolactin, ACTH and cortisol and less deep sleep after dosing. Long-term safety has not been tested in controlled trials, and growth hormone release weakens with repeated use. Does hexarelin affect the heart? In small single-dose studies it raised left ventricular ejection fraction in healthy men and in men with growth hormone deficiency, and raised cardiac output during bypass surgery for up to 90 minutes. Growth hormone itself did not do this, so the effect seems to run through cardiovascular mechanisms rather than circulating growth hormone. Long-term heart effects are unknown. What is the hexarelin dosage? There is no FDA-approved dose. Injection studies in people set doses by body weight, mostly as single test injections into a vein, with one 16-week course of twice-daily injections under the skin in older adults. Short studies of intranasal and oral hexarelin used fixed amounts. The study doses are listed in the dosage table on this page. Your clinician sets your dose. Does hexarelin stop working over time? Partly. In 12 healthy older adults given repeated injections for 16 weeks, the growth hormone response fell by close to half and returned to about its starting level after a four-week break. Short intermittent courses by nose or mouth did not blunt it. Hexarelin vs GHRP-2: what is the difference? In a direct comparison in healthy adults the two released similar, strong amounts of growth hormone and raised prolactin, ACTH and cortisol alike. Hexarelin has heart studies behind it. FDA lists GHRP-2 on its compounding safety page and does not list hexarelin. Is hexarelin FDA approved? No. Hexarelin is not an FDA-approved drug and is not among the six peptides covered by the October 2026 enforcement discretion. Is hexarelin banned in sports? Growth hormone secretagogues and releasing factors fall in the S2 class of the WADA Prohibited List, which applies in and out of competition. Tested athletes should not use hexarelin. Can I get hexarelin through Vitals Vault? Vitals Vault is opening clinician-led peptide care that starts with a blood test. Join the peptides waitlist to hear first. A licensed clinician reviews your history and labs and decides what, if anything, is right for you. ## Peptides, prescribed and measured Vitals Vault is opening peptide care that starts with your blood work, is prescribed by licensed US clinicians and ends with a retest. Join the waitlist to hear first. - Prescription only - Licensed US clinicians - Quest Diagnostics labs [Get early access to peptide care](https://www.vitalsvault.com/peptides-waitlist)[Start with 120+ lab tests · $99](https://www.vitalsvault.com/labs#plans) ## Keep reading [Full Peptide Guide](https://www.vitalsvault.com/peptides) - GHRP-2A six-amino-acid ghrelin-receptor agonist that triggers a sharp pulse of growth hormone. Used in Japanese diagnostic research. - GHRP-6An early synthetic ghrelin-receptor peptide, a six-amino-acid chain that triggers growth hormone release. - IpamorelinA five-amino-acid growth hormone secretagogue that mimics ghrelin, studied for its selective release of growth hormone. - FDA peptide update 2026What FDA’s October 2026 decision on six peptides means for you. - CJC-1295A long-acting growth hormone releasing hormone analog, studied for raising growth hormone and IGF-1. ## Sources 1. 1. [Howard AD, et al. A receptor in pituitary and hypothalamus that functions in growth hormone release. Science. 1996 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/8688086/) 2. 2. [Kojima M, et al. Ghrelin is a growth-hormone-releasing acylated peptide from stomach. Nature. 1999 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/10604470/) 3. 3. [Arvat E, et al. Effects of GHRP-2 and hexarelin, two synthetic GH-releasing peptides, on GH, prolactin, ACTH and cortisol levels in man. Peptides. 1997 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/9285939/) 4. 4. [Ghigo E, et al. Short-term administration of intranasal or oral Hexarelin, a synthetic hexapeptide, does not desensitize the growth hormone responsiveness in human aging. Eur J Endocrinol. 1996 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/8921821/) 5. 5. [Rahim A, et al. Does desensitization to hexarelin occur? Growth Horm IGF Res. 1998 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/10990150/) 6. 6. [Rahim A, et al. The effect of chronic hexarelin administration on the pituitary-adrenal axis and prolactin. Clin Endocrinol (Oxf). 1999 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/10341859/) 7. 7. [Bisi G, et al. Cardiac effects of hexarelin in hypopituitary adults. Eur J Pharmacol. 1999 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/10528131/) 8. 8. [Broglio F, et al. Effects of acute hexarelin administration on cardiac performance in patients with coronary artery disease during by-pass surgery. Eur J Pharmacol. 2002 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/12144941/) 9. 9. [Ghigo E, et al. Growth hormone-releasing peptides. Eur J Endocrinol. 1997 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/9186261/) 10. 10. [Bodart V, et al. CD36 mediates the cardiovascular action of growth hormone-releasing peptides in the heart. Circ Res. 2002 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/11988484/) 11. 11. [Berlanga-Acosta J, et al. Synthetic growth hormone-releasing peptides (GHRPs): a historical appraisal of the evidences supporting their cytoprotective effects. Clin Med Insights Cardiol. 2017 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/28469491/) 12. 12. [Frieboes RM, et al. Hexarelin decreases slow-wave sleep and stimulates the secretion of GH, ACTH, cortisol and prolactin during sleep in healthy volunteers. Psychoneuroendocrinology. 2004 (opens in a new tab)](https://pubmed.ncbi.nlm.nih.gov/15177700/) 13. 13. [FDA. Certain bulk drug substances for use in compounding that may present significant safety risks (current as of April 22, 2026) (opens in a new tab)](https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks) 14. 14. [NCPA. FDA grants enforcement discretion for compounding six peptides. October 29, 2026 (opens in a new tab)](https://ncpa.org/newsroom/qam/2026/10/29/fda-grants-enforcement-discretion-compounding-six-peptides) 15. 15. [World Anti-Doping Agency. Prohibited List (opens in a new tab)](https://www.wada-ama.org/en/prohibited-list) Written by the Vitals Vault editorial team, medically reviewed by Robert Lufkin, MD, and updated October 29, 2026. This is general education, not medical advice. None of these peptides is FDA-approved to diagnose, treat, cure or prevent any disease, and compounded medicines are not FDA-reviewed for safety, effectiveness or quality. Talk to a licensed clinician before starting any treatment. --- Canonical HTML: https://www.vitalsvault.com/peptides/hexarelin - [llms.txt](https://www.vitalsvault.com/llms.txt) - [sitemap.xml](https://www.vitalsvault.com/sitemap.xml) - [Developer portal](https://www.vitalsvault.com/developers)