PepRank

Hexarelin

45%positive5 reports

Also: examorelin · 'hex'

ExcludedRecoveryMetabolicInjection

Most potent GHRP; fast desensitisation, acute cortisol/prolactin rise and direct CD36 heart effects.

#38 of 61 research peptides · updated
Access
Grey market
Cost / month
≈ €27–110
researchers' estimate; no listing to price
InjectionFelt in 0 min – 1 h, lasts 2 h
5 user reports
Positive 2Mixed 2Negative 1
  • r/BodyHackGuide· · 3 upvotesOriginal ↗

    Hexarelin is awesome as a ghrp but strong. If you run it treat it like igf1-lr3. Month on then a month off. Hexarelin will burn out your receptors.

    PositiveRecovery · Injection · 4-week blocks

    stacked with tesamorelin, CJC-1295/ipamorelin, 4 IU GH and IGF-1 LR3

  • r/Peptidesource· · 1 upvotesOriginal ↗

    The protocol was 10mg (2mL dilution) over 14 days. 14 days off. Then 10mg over 14 days. He was pleased with the outcome. He said it is powerful, so note all changes and stay aware.

    PositiveRecovery · 10 mg over 14 days, 14 off, repeated · Injection

    written in the 'rat subject' framing the subreddit requires

  • r/BodyHackGuide· · 1 upvotesOriginal ↗

    That Hexarelin gone have you tired and sore. I take 100 mcg a day and feels like I got the flu.

    NegativeRecovery · 100 mcg/day · Injection

    also on retatrutide/cagrilintide and CJC-1295/ipamorelin, which caused no side effects

Strict case
GH/IGF-1 axis elevation, acute cortisol and prolactin release, and GH-independent actions on heart and coronary vessels via CD36.
Users report
Only five first-hand reports, too few to judge. Users describe it as the strongest GHRP ('powerful', 'awesome but strong'), cycled a month on and a month off because the response 'burns out'. One user felt better than ever but watched his resting heart rate climb; another gets a flu-like, tired, sore feeling at 100 mcg a day. One raised the dose expecting prolactin or cortisol side effects and got only strong hunger. Most replies to hexarelin threads advise switching to ipamorelin or plain GH, and warn about gynecomastia from prolactin, though no first-hand case appears. Felt nothing: None of the 5 reports felt nothing, but there are too few to say..
Best effects
Largest acute GH pulse of the GHRPs · strong hunger · acute rise in heart contractility (in studies)
Downsides
Response fades within weeks of daily use · flu-like tiredness and soreness for some · resting heart rate increase (one report) · hunger
Watch
GH/IGF-1 axis elevation (glucose, theoretical neoplasm promotion) · Acute ACTH, cortisol and prolactin release after each dose (Arvat 1997; Maccario 2002) · Binds CD36 in heart and vessels: raised coronary perfusion pressure (vasoconstriction) in perfused rodent hearts · Acute positive inotropic effect in humans; long-term cardiac effects of repeated dosing unstudied
Evidence
Small human studies — Acute dosing in volunteers and patients; one 16-week trial in 12 elderly adults; developed in the 1990s, never approved
Caveat
The prolactin and cortisol rises are well documented after single IV doses but did not persist with modest twice-daily subq dosing over 16 weeks; community doses are often higher. The cardiac findings are acute and partly in heart patients, so they say little about months of use either way.
Typical use
Users: 100-200 mcg subq 1-2x/day, fasted, 4 weeks on and 4 off. Trials used 1-2 mcg/kg IV or 1.5 mcg/kg subq twice daily.
Getting it
Research-peptide vials (2-5 mg) and blends with GHRP-6 and mod-GRF. Never approved anywhere; WADA-prohibited as examorelin.
Stacked with
Tesamorelin or CJC-1295: Run together for a bigger GH pulse; users pair a GHRH in the morning with hexarelin before training. · Ipamorelin: Rotated in during hexarelin's off-months to avoid desensitisation. · Cabergoline: Commenters tell hexarelin users to keep it on hand against prolactin; no first-hand report shows it was needed.

User reports 5

  • r/BodyHackGuide· · 3 upvotesOriginal ↗

    Hexarelin is awesome as a ghrp but strong. If you run it treat it like igf1-lr3. Month on then a month off. Hexarelin will burn out your receptors.

    PositiveRecovery · Injection · 4-week blocks

    stacked with tesamorelin, CJC-1295/ipamorelin, 4 IU GH and IGF-1 LR3

  • r/Peptidesource· · 1 upvotesOriginal ↗

    The protocol was 10mg (2mL dilution) over 14 days. 14 days off. Then 10mg over 14 days. He was pleased with the outcome. He said it is powerful, so note all changes and stay aware.

    PositiveRecovery · 10 mg over 14 days, 14 off, repeated · Injection

    written in the 'rat subject' framing the subreddit requires

  • r/BiohackingU· · 28 upvotesOriginal ↗

    i genuinely have never felt better. but realised my resting HR is increasing after taking Hexarelin

    MixedRecovery · Injection

    stacked with several secretagogues and MK-677; most replies told him to switch to GH

  • r/DrWillPowers· · 1 upvotesOriginal ↗

    I was waiting for some prolactin/cortisol side effects as I upped the dose a decent bit but all I got was hungry as fuck

    MixedRecovery · Injection

    taking it after a shoulder fracture; author since deleted

  • r/BodyHackGuide· · 1 upvotesOriginal ↗

    That Hexarelin gone have you tired and sore. I take 100 mcg a day and feels like I got the flu.

    NegativeRecovery · 100 mcg/day · Injection

    also on retatrutide/cagrilintide and CJC-1295/ipamorelin, which caused no side effects

Safety

Tier by safety barStrict ExcludedBalanced CautionEvidence only Caution

Seen harmMechanismData gapSilent harmProduct

Seen harm 0/3
No published case reports, label warnings or trial SAE signals in the human studies, which include a 16-week trial in 12 elderly adults and acute IV dosing in heart-failure and bypass-surgery patients. Reddit adds one rising resting heart rate and one flu-like reaction, neither serious. The zero reflects small documented exposure, not reassurance. Rahim et al. 1998: 16 weeks of twice-daily hexarelin in 12 elderly adults ↗Mao 2014: the cardiovascular action of hexarelin (review of human cardiac studies) ↗r/BiohackingU: resting heart rate increasing after hexarelin ↗
Mechanism 2/3
Two credible pathways. Hormone axis: the strongest GH release of the GHRPs plus acute prolactin, ACTH and cortisol rises comparable to a CRH challenge (though these did not persist at 1.5 mcg/kg twice daily over 16 weeks). Heart: it binds CD36, raised coronary perfusion pressure (vasoconstriction) in perfused rodent hearts and acutely raises ejection fraction in people independently of GH. No in-vivo demonstration of serious harm, so 2. Arvat et al. 1997: hexarelin raises prolactin, ACTH and cortisol in man ↗Rahim et al. 1999: chronic hexarelin and the pituitary-adrenal axis and prolactin ↗Bodart et al. 2002: CD36 mediates the cardiovascular action of GHRPs (Circ Res) ↗Bisi et al. 1999: acute cardiovascular effects of hexarelin in humans ↗
Data gap 2/3
Never approved. Human data are small studies: acute IV challenges in groups of 6-20, one 16-week subq trial in 12 elderly adults, and 6-10 months of intranasal dosing in 7 children. No controlled trial of repeated subcutaneous use in healthy adults. Rahim et al. 1998: long-term hexarelin, 12 adults ↗Klinger et al. 1996: long-term intranasal hexarelin in 7 short children ↗
Silent harm 3/3
The feared harms are theoretical IGF-1-driven tumour promotion and unknown long-term effects of repeated CD36 and inotropic stimulation on the heart and coronary vessels, both silent and delayed (3). Glucose effects would show on a blood test; hunger and flu-like feelings are immediate. Renehan et al. 2004: IGF-I and cancer risk ↗Bodart et al. 2002: CD36 and coronary vasoconstriction ↗
Product 3/3
Bought as grey-market injectable vials (2-5 mg) or premixed 'gaining blends' with GHRP-6 and mod-GRF, reconstituted at home and injected daily. Mendias & Awan 2026 preprint: grey-market peptide quality ↗r/Testosterone: a 'gaining blend' of hexarelin, GHRP-6 and mod GRF ↗
Never if
Pregnancy or breastfeeding (no human reproductive data) · Active or past cancer · Coronary artery disease, heart failure or arrhythmia (direct cardiac and coronary CD36 effects) · Diabetes or prediabetes · Pituitary tumours, including prolactinoma · Under 18

Studies 8

Sources 4

More in Hormones & libido all 12 →

  1. 1GHRP-6 Excluded Injection≈ €13–81 / month59%positive14 reportsFirst-generation GHRP used as an appetite drug for bulking; strong hunger, cortisol, glucose, GH axis.GH/IGF-1 axis elevation plus cortisol rise and reduced insulin sensitivity (FDA), with only single-dose human safety data.
  2. 2Kisspeptin YNWNSFGLRF (10 residues) Excluded Nasal / Injection≈ €4.1–12 / month52%positive30 reportsTop-of-axis GnRH stimulator for libido/testosterone; chronic use can crash the axis.Directly manipulates the HPG axis; continuous or long-acting exposure suppresses it.
  3. 3IGF-1 DES Excluded Injection≈ €22–180 / month49%positive4 reportsShort-acting, truncated IGF-1 injected into the trained muscle; very potent at dropping blood sugar.An IGF-1 receptor agonist about ten times as potent as IGF-1 in cells and the most hypoglycaemic of the IGF-1 variants in primates, with no human data, the same tumour-promotion concern as LR3, and grey-market vials that are rarely tested.
  4. 4MK-677 Excluded Oral≈ €18–54 / month48%positive29 reportsOral GH secretagogue (not a peptide); hunger, bloat, insulin resistance, CHF signal.GH/IGF-1 elevation, insulin resistance and a CHF safety signal in an RCT.
  5. 5Follistatin-344 Excluded Injection≈ €180–450 / month44%positive10 reportsMyostatin/activin-binding protein sold as 1 mg vials; about half of tested vials held no follistatin.Blocks myostatin and activin signalling (FSH axis, angiogenesis, glucose) with no human safety data for the injected protein; vials often hold other drugs.
  6. 6IGF-1 LR3 Excluded Injection≈ €36–140 / month40%positive24 reportsLong-acting IGF-1 analogue (a cell-culture reagent) for muscle; hypoglycaemia, tumour-growth signal.A potent, long-acting IGF-1 receptor agonist with no human data at all: it accelerated tumour growth in mice, the same receptor causes hypoglycaemic seizures and carries a malignancy warning on the approved IGF-1 drug, and every vial is grey-market.
  7. 7Sermorelin YADAIFTNSYRKVLGQLSARKLLQDIMSR (29 residues) Excluded Sublingual / Injection≈ €38–94 / month46%positive29 reportsShort GHRH analogue; cheap, gentle, sleep-focused, still GH/IGF-1 axis.GH/IGF-1 axis elevation, though the mildest of the class.
  8. 8PT-141 DHFRWK (6 residues) Excluded Nasal / Injection≈ €24–170 / month39%positive30 reportsFDA-approved melanocortin libido drug; works strongly for many, raises blood pressure.Cardiovascular effects (BP spikes; contraindicated in CVD) and melanocortin pigmentation effects.
  9. 9GHRP-2 Excluded Injection / Nasal / IV≈ €18–45 / month39%positive7 reportsJapan-approved GH diagnostic sold as a vial; hunger, cortisol and prolactin spikes, GH axis.GH/IGF-1 axis elevation with cortisol and prolactin spikes; FDA notes raised insulin needs and deaths in critically ill subjects.
  10. 10Ipamorelin Excluded Injection≈ €11–100 / month42%positive51 reportsSelective ghrelin-receptor GH secretagogue; sleep and recovery, GH axis plus reactions.GH/IGF-1 axis elevation plus repeated anaphylaxis reports, including a coroner-attributed death.
  11. 11CJC-1295 YADAIFTQSYRKVLAQLSARKLLQDILSR (29 residues) Excluded Injection≈ €14–27 / month38%positive29 reportsLong-acting GHRH analogue stacked with ipamorelin; GH axis, vasodilatory reactions.GH/IGF-1 axis elevation plus FDA-noted tachycardia/vasodilatory reactions and anaphylaxis.

Sequence beads

Each bead is one amino acid in the peptide's chain, coloured by its side chain: grey for non-polar, cyan for polar, blue for positively charged and fuchsia for negatively charged. Length and mix tell related peptides apart at a glance, from a two-residue dipeptide like carnosine to a 43-residue protein like thymosin beta-4. The colours describe chemistry only and predict neither effect nor safety.

non-polarpolarpositivenegative

Report grades

Every first-hand Reddit or X report is graded on its own, from glowing through positive, mixed, nothing and negative to bad reaction, and the bar shows how those grades split. Posts that look vendor-adjacent stay on the peptide's page but are left out of the counts.

GlowingPositiveMixedNothingNegativeBad reaction

% positive

The share of a peptide's graded Reddit and X reports that are glowing or positive, vendor-adjacent posts left out. A peptide with few reports is pulled toward the average of all reports, as if it had eight average ones besides its own, so two glowing posts cannot top the list. Kept peptides rank by the same reports' mean grade, shrunk the same way, and excluded ones follow in that order.

Researcher estimate

No first-hand report of this peptide has been graded yet, so the figure is the researchers' own rating out of 10 from what they read about it. It ranks alongside the computed scores until reports arrive.

Safety tier

Each peptide is tiered clean, caution or excluded from its five risk axes under the chosen safety bar. An excluded peptide has a plausible route to serious harm, so it stays listed with the reason but ranks behind every other entry, however good its reviews.

Safety bar

The safety bar sets how much risk it takes to exclude a peptide. Strict: out on any serious mechanism with little human data, or any documented serious harm. Balanced: out on documented serious harm (unless it is obvious, reversible and from a regulated product), or a serious mechanism whose harm would be silent with no human data at all. Evidence only: out only on documented serious harm in humans that is lasting, delayed or from grey-market product.

Seen harm

Documented serious adverse events in humans, from 0 for none despite real exposure to 3 for deaths or several well-documented serious harms. Serious means a hospital or emergency visit or harm lasting weeks, so a headache or a bad night does not count.

Mechanism

A plausible biological route to serious harm at the doses people use, such as growth-factor signalling, hormone-axis suppression, heart or blood-pressure effects or immune activation. It runs from 0 when none is known to 3 when a dangerous pathway has been shown in living animals.

Data gap

How little human safety data exists for the molecule actually sold, from 0 for an approved drug with large trials and years of use to 3 for no human safety data at all. A modified analogue does not inherit its parent's trials.

Silent harm

Whether the feared harm would show quickly or stay hidden, from 0 when it is obvious and goes on stopping to 3 when it is silent and delayed, like tumour promotion or slow organ damage. User reports cannot reveal a harm that takes years to appear, so a high score here limits what good reviews can tell you.

Product

The risk of what people actually buy, from 0 for a regulated pharmacy or supplement product taken by mouth or on the skin to 3 for a grey-market injectable. In one dataset of 6,441 grey-market samples, 42–71% failed basic quality criteria and 15% carried endotoxin.

Evidence

The strongest kind of study behind the peptide's effects, from an approved drug through human controlled trials and small human studies to animal work or nothing of its own. Animal results often fail to carry over to people.

Access

How people get it: as an approved drug, a compounded prescription, an over-the-counter supplement or from the grey market, where nobody checks the vial. The channel decides both the legal position and the risk of a bad batch.

Price per month

Thirty days of the typical dose, from its low end to its high end, priced at the listing a careful buyer would choose: in stock, from a shop scoring 4 of 5 on trust (third-party tested where no score is set), failing that 3, a pure pack before a blend, a European shop first, then the cheapest per mg. The range is the dose's, not the shops'. A per-dose amount counts once a day unless the dose says otherwise. Prices are in euros at ECB rates of 2026-10-29, before shipping; the shop table keeps each listing's price per mg, per gram for bulk supplements. Where no listing can be priced the researchers' own estimate stands in, and says so.

Dose users report

The middle half of the daily doses stated in at least five first-hand reports, vendor posts left out. Where its middle sits more than twice above or below the declared dose, the month is priced at it as well, since what people take is what they pay for.

Testing

Whether the shop publishes lab results: third-party tested means an independent lab checks each batch, own COA means the shop's own certificate of analysis, and no public tests means neither. A certificate shows purity, not safety.

Added peptide

Some packs sold under one peptide's name hold a second one, such as 5 mg GHK-Cu in a nasal kit, stated only in the description. Sprayed in the nose or injected it reaches the blood like an injection, so it carries the risk of that route and is tiered as the injectable form, whatever its tier on the skin. A pack whose page gives no contents list may hold more than its name.