MEDICAL DISCLAIMER: Educational research guidelines only. Lyophilized peptides are investigational chemical compounds and are NOT approved for human consumption, diagnosis, or therapy. Consult a licensed physician before any research application.
Hexarelin Dosage Chart, Schedule & Reconstitution Protocol
Quickstart Highlights
Hexarelin (examorelin) is a synthetic hexapeptide growth hormone secretagogue and GHS-R1a (ghrelin-receptor) agonist derived from GHRP-6. It triggers a strong, short-lived GH pulse from the pituitary — about twice the GH of an equimolar GHRH dose in humans (PMID 8126144) — and also binds the cardiac CD36 receptor, the basis for its much-studied but unapproved cardiovascular effects (PMID 11988484). Research and community protocols typically use about 100 mcg subcutaneously, one to three times daily, near the 1-2 mcg/kg range that gives a near-maximal GH response (PMID 7957536). The GH response saturates around 100 mcg, so larger per-dose amounts mainly raise cortisol and prolactin. Its half-life is short (~55-76 min), and chronic twice-daily use causes a partial, reversible decline in GH response over weeks (PMID 9589671). Hexarelin is not approved by the FDA or EMA, is prohibited by WADA, and is sold for research use only. This page is educational, not medical advice.
Reconstitute: Add 2.5 mL bacteriostatic water → 2 mg/mL concentration.
Typical dose: 100 mcg per dose, 1-3x/day SC (≈1-2 mcg/kg)
Easy measuring: At 2 mg/mL, 1 unit = 0.01 mL = 0.0200 mg (20 mcg) on a U-100 insulin syringe.
Storage: Lyophilized powder stored frozen at −20 °C and protected from light; reconstituted solution refrigerated at 2-8 °C and used within ~4 weeks.
Half-life: Short — roughly 55 min in humans (~76 min IV in rats); GH peaks ~15-30 min and returns to baseline within ~4 h, so dosing is pulsed 1-3x/day (PMID 10611139).
Route: Subcutaneous or intravenous injection — a genuine research route (SC bioavailability ~64%); oral bioavailability is very low. Modeled here as a 5 mg vial in 2.5 mL = 20 mcg per insulin-syringe unit.
Status: Not FDA- or EMA-approved; reached Phase II for GH deficiency; WADA-prohibited; research and educational use only.
About Hexarelin
Hexarelin (examorelin) is a six-amino-acid growth hormone secretagogue that activates the GHS-R1a (ghrelin) receptor to trigger a sharp, pulse-like release of growth hormone from the pituitary [1]. Unlike many compounds catalogued on this site, the subcutaneous route modeled below is genuine: the pivotal human studies dosed hexarelin intravenously and subcutaneously, and subcutaneous bioavailability was about 64% in animal work, so these reconstitution figures map onto how the peptide is actually researched [1][3]. Oral bioavailability, by contrast, is very low, which is why injectable dosing dominates.\n\nThis guide models a 5 mg vial reconstituted with 2.5 mL of bacteriostatic water (2 mg/mL, or 20 mcg per insulin-syringe unit) so the common Hexarelin dosage lands on clean marks: 100 mcg = 5 units, 150 mcg = 7.5 units, and 200 mcg = 10 units on a U-100 syringe. Controlled studies established an ED50 near 0.5 mcg/kg and a near-maximal GH response at about 1-2 mcg/kg, which is roughly 100-150 mcg for most adults [1][2].\n\nA practical detail behind any Hexarelin protocol: the GH response saturates around 100 mcg, so going higher per dose mainly increases cortisol and prolactin rather than GH [2][5]. Chronic twice-daily use also blunts the GH response partially and reversibly over several weeks [4], which is why many research protocols cycle the peptide.\n\nFrequency: Inject one to three times daily subcutaneously (commonly twice daily, roughly 8 hours apart) on an empty stomach, away from dietary fat. Hexarelin is not FDA- or EMA-approved and is presented here for educational purposes only.
Quick Protocol Navigation
Reconstitution Instruction & Mixing Step-by-Step
Lyophilized powder must be reconstituted carefully. Agitating peptide chains can shear disulfide bonds and render the peptide biologically inert.
Draw 2.5 mL of bacteriostatic water into a sterile syringe (this yields a 2 mg/mL solution from a 5 mg vial — 20 mcg per insulin-syringe unit).
Inject the water slowly down the inner wall of the 5 mg vial; do not spray directly onto the powder and avoid foaming or vigorous shaking.
Gently swirl or roll the vial until the solution is completely clear; do not shake, as agitation can degrade the peptide.
Store refrigerated at 2-8 °C and use within ~4 weeks; draw 5 units (100 mcg), 7.5 units (150 mcg), or 10 units (200 mcg) on a U-100 syringe.
Swab the site (abdomen or thigh), inject subcutaneously on an empty stomach (ideally 1-2 hours away from food and dietary fat), and rotate sites between doses.
Interactive Hexarelin Syringe Calculator
Currently visualizing the 5 mg vial reconstituted with 2.5 mL bacteriostatic water. Adjust the target dose to dynamically render syringe units.
Reconstitution Calculation: 5mg dry powder in 2.5mL water yields 2.00 mg/mL. To evaluate a 250mcg dose, pull to 12.5 units (13 syringe ticks).
U-100 Syringe Representation
Educational reference visual. Assumes standard U-100 insulin syringe where 1.0 mL volume = 100 units.
Titration & Dose Escalation Schedules
| Phase | Dose per injection | Units (per injection) |
|---|---|---|
| Weeks 1-2 — acclimation, once daily before bed | 100 mcg | 5 units (0.05 mL) |
| Weeks 3-8 — standard protocol, 2-3x daily on an empty stomach | 100 mcg | 5 units (0.05 mL) |
| Per-dose ceiling — GH response saturates near 100 mcg; higher mainly raises cortisol/prolactin | 200 mcg | 10 units (0.10 mL) |
Administration guidelines: Refer to guidelines | 2.5 mL Reconstitution
Research Supplies Quantity Planner
Scientific mathematical planning of syringes, bacteriostatic water and dry vials needed for extended research blocks using the 5 mg vial.
Peptide Vials (Hexarelin, 5 mg each):
- check8 weeks at 100 mcg twice daily (112 doses, 11.2 mg) ≈ 3 vials
- check12 weeks (168 doses, 16.8 mg) ≈ 4 vials
- check16 weeks (224 doses, 22.4 mg) ≈ 5 vials
- checkA reconstituted 5 mg vial holds ~50 doses at 100 mcg; discard after ~4 weeks even if peptide remains, and add ~50% more vials if dosing 3x/day
Insulin Syringes (U-100):
- checkTwice-daily dosing: 14 syringes per week (21/week if dosing 3x/day)
- check8 weeks ≈ 112 syringes; 12 weeks ≈ 168 syringes
- check16 weeks ≈ 224 syringes; use a fresh 0.3 mL/31 G insulin syringe for each injection
Bacteriostatic Water (30 mL bottles): Use 2.5 mL per 5 mg vial for reconstitution.
- check8 weeks (~3 vials) ≈ 7.5 mL
- check12 weeks (~4 vials) ≈ 10 mL
- check16 weeks (~5 vials) ≈ 12.5 mL — one 30 mL bottle covers a full course
Alcohol Swabs:
- check1-2 swabs per dose (vial top + injection site)
- check8 weeks ≈ 112-224 swabs; 12 weeks ≈ 168-336 swabs
- check16 weeks ≈ 224-448 swabs; keep extras for re-swabbing the multi-dose vial
Mechanism of Action (MOA)
Hexarelin is a synthetic hexapeptide (His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH2) built on the GHRP-6 template, with backbone modifications that improve metabolic stability and GH-releasing potency relative to the parent peptide [8]. Its primary target is the growth hormone secretagogue receptor type 1a (GHS-R1a), the same Gq-coupled receptor activated by endogenous ghrelin. Binding GHS-R1a on pituitary somatotrophs activates phospholipase C, mobilises intracellular calcium, and triggers exocytosis of stored growth hormone; in parallel it acts on hypothalamic neurons to amplify GHRH signalling and to blunt inhibitory somatostatin tone. The net effect is a large, discrete GH pulse rather than a continuous elevation — in healthy volunteers an intravenous 1 mcg/kg dose released roughly twice the GH of an equimolar dose of GHRH [1].\n\nThe dose-response is steep but quickly saturable. Imbimbo and colleagues found an ED50 near 0.5 mcg/kg for both peak GH and area-under-the-curve, with a 2 mcg/kg dose producing a near-maximal response [2]. Because the somatotroph releasable pool is finite, GH output plateaus around 100 mcg in a typical adult; pushing the per-dose amount higher recruits little additional GH while engaging corticotrophs and lactotrophs, raising ACTH/cortisol and prolactin [2][5].\n\nPharmacokinetics: hexarelin acts fast and clears fast. Plasma GH peaks roughly 15-30 minutes after injection and returns to baseline within about 4 hours, and the peptide's own elimination half-life is short — on the order of 55 minutes in humans and about 76 minutes (intravenous) in rats, where systemic clearance was 7.6 mL/min/kg and subcutaneous bioavailability about 64% [1][3]. Elimination is largely via biliary excretion of intact peptide [3]. This short half-life, combined with receptor desensitisation, is why hexarelin is dosed in repeated daily pulses rather than continuously.\n\nA defining feature is tachyphylaxis. With twice-daily 1.5 mcg/kg subcutaneous dosing over 16 weeks, the GH response fell significantly by weeks 4 and 16, but recovered to baseline four weeks after stopping — a partial, fully reversible attenuation [4]. Reassuringly, the same regimen did not over-stimulate the pituitary-adrenal axis: urinary free and basal cortisol were unchanged, and ACTH and prolactin responses were not meaningfully altered at chronic therapeutic doses [5].\n\nHexarelin is also unusual in acting outside the GH axis. It binds CD36, a scavenger receptor expressed on cardiomyocytes and vascular tissue, and produces cardioprotective and vasodilatory effects that persist in hypophysectomised animals and disappear in CD36-null mice — establishing a growth-hormone-independent cardiovascular mechanism [6][7]. This dual GHS-R1a/CD36 pharmacology drove Phase II interest in both GH-deficiency diagnostics and cardiac indications, though no cardiovascular benefit has been confirmed in humans and development was not completed [7][8]. The subcutaneous protocol here reflects a genuine research route, but hexarelin remains investigational and unapproved.
Clinical Trial Efficacy Highlights
- starGhigo, Arvat and colleagues (1994, J Clin Endocrinol Metab) gave hexarelin to healthy young volunteers by intravenous, subcutaneous, intranasal and oral routes; intravenous 1 mcg/kg released roughly twice the GH of an equimolar dose of GHRH, and the subcutaneous and intranasal routes were also effective while oral activity was weak, characterizing hexarelin as a potent, route-flexible GH secretagogue [1].
- starImbimbo and colleagues (1994, Eur J Clin Pharmacol) ran a double-blind, placebo-controlled dose-response study in twelve men using intravenous doses of 0.5, 1 and 2 mcg/kg; GH release was dose-dependent with calculated ED50 values of 0.50 mcg/kg for peak GH and 0.64 mcg/kg for AUC, and a 2 mcg/kg dose gave a near-maximal response — the basis for the ~1-2 mcg/kg clinical reference [2].
- starRoumi and colleagues (2000, Drug Metab Dispos) characterized hexarelin pharmacokinetics in rats, reporting an intravenous half-life of about 76 minutes, systemic clearance of 7.6 mL/min/kg, subcutaneous bioavailability near 64%, and predominantly biliary excretion of intact peptide — explaining why the compound is injected and dosed in repeated daily pulses [3].
- starRahim, O'Neill and Shalet (1998, J Clin Endocrinol Metab) treated healthy elderly subjects with 1.5 mcg/kg subcutaneous hexarelin twice daily for 16 weeks; the GH response (AUC) declined significantly by weeks 4 and 16 but returned toward baseline four weeks after stopping, demonstrating that the desensitization is partial and reversible [4].
- starRahim, O'Neill and Shalet (1999, Clin Endocrinol) examined the pituitary-adrenal axis and prolactin during the same 16-week regimen and found no over-stimulation: urinary free cortisol, basal cortisol and CBG were unchanged and ACTH/prolactin responses were not meaningfully altered, with only a transient, reversible reduction in the cortisol response, supporting reasonable endocrine tolerability at therapeutic doses [5].
- starBodart and colleagues (2002, Circulation Research) identified CD36 as the cardiac binding site that mediates the cardiovascular action of GH-releasing peptides including hexarelin; the vascular effects were abolished in CD36-null mice, establishing a receptor distinct from GHS-R1a and a GH-independent cardiac mechanism [6].
- starMao, Tokudome and Kishimoto (2014, J Geriatr Cardiol) reviewed hexarelin's cardiovascular pharmacology, describing dual action through GHSR and CD36, greater chemical stability and potency than native ghrelin, and preclinical cardioprotective and vasodilatory effects; the authors emphasize therapeutic potential that has not yet been confirmed in completed human cardiovascular trials [7].
- starPer the development record summarized for examorelin/hexarelin, the peptide reached Phase II clinical testing for the treatment of growth hormone deficiency but was never approved, and reported results did not translate into a marketed product, underscoring that human efficacy beyond acute GH release remains unproven [8].
Side Effects & Tolerability Profile
Clinical subjects transiently report mild side effects. Slowly escalating the titration dose represents the single most effective intervention to limit side effects.
- warningTransient flushing, warmth, sweating, and tingling or numbness of the face, head or hands shortly after injection are common with potent GHRPs and usually fade within minutes [1].
- warningIncreased appetite and hunger through ghrelin-receptor (GHS-R1a) agonism, sometimes with mild nausea or gastrointestinal discomfort, especially at higher per-dose amounts [8].
- warningElevations in cortisol and prolactin when single doses exceed roughly 100 mcg, because excess hexarelin engages corticotrophs and lactotrophs; selectivity is poorer than with ipamorelin [2][5].
- warningWater and sodium retention, mild peripheral edema, joint aches (arthralgia), and carpal-tunnel-like tingling can occur from GH/IGF-1 elevation, typically early in use.
- warningSustained GH elevation can transiently reduce insulin sensitivity and raise blood glucose; caution is warranted in people with prediabetes, diabetes, or metabolic syndrome.
- warningTachyphylaxis: the GH response declines partially over weeks of daily dosing and recovers after a washout, so continuous high-frequency use yields diminishing returns [4].
- warningLong-term human safety is not established; theoretical concerns include effects on glucose metabolism, soft-tissue growth, and proliferation, and the cardiovascular effects seen preclinically have not been validated in completed human trials [7].
- warningRegulatory/research status: hexarelin is NOT approved by the FDA or EMA, is on the WADA Prohibited List, cannot legally be sold as a dietary supplement, and is offered for research use only; this page is educational, not medical advice [8].
Subcutaneous Injection Technique
Most research peptides require subcutaneous injection into fatty tissue. Never inject directly into a blood vessel or deep muscle tissue unless clinically detailed.
1. Site Selection
Common locations include the abdomen (2 inches from navel), outer upper arms, or thighs.
2. Sanitization
Thoroughly clean the selected site, stopper and vial top using 70% isopropyl alcohol prep swabs.
3. Angle & Push
Pinch the skin and insert the needle at a 45 to 90-degree angle. Depress plunger smoothly.
4. Site Rotation
Rotate injection sites continuously to avoid lipodystrophy or tissue scarring.
Frequently Asked Questions
What is the typical Hexarelin dosage?expand_more
In research and community protocols the typical Hexarelin dosage is about 100 mcg per subcutaneous injection, given one to three times daily (often twice daily, roughly 8 hours apart, on an empty stomach). This sits near the 1-2 mcg/kg range that produced a near-maximal GH response in controlled human studies, where the ED50 was about 0.5 mcg/kg and a 2 mcg/kg dose was near-maximal. Because the GH response saturates around 100 mcg, going higher per dose mainly raises cortisol and prolactin rather than GH, so most protocols cap each injection near 100-150 mcg. This is educational information, not medical advice.
Is Hexarelin FDA approved?expand_more
No. Hexarelin (examorelin) is not approved by the FDA or the EMA for any indication. It was developed by Mediolanum Farmaceutici and reached Phase II clinical testing for growth hormone deficiency, but it was never approved or marketed. It is on the WADA Prohibited List, cannot legally be sold as a dietary supplement, and is offered only for research use. Everything on this page is educational and not medical advice.
What is the half-life of Hexarelin?expand_more
Hexarelin has a short half-life — roughly 55 minutes in humans and about 76 minutes after intravenous dosing in rats. The GH pulse it triggers peaks about 15-30 minutes after injection and returns to baseline within roughly 4 hours, and the peptide is eliminated largely through biliary excretion. This short duration of action, together with receptor desensitization over time, is why hexarelin is dosed in repeated daily pulses rather than as a single long-acting injection.
How is Hexarelin reconstituted and administered?expand_more
Hexarelin is reconstituted with bacteriostatic water and injected subcutaneously, which is a genuine research route (subcutaneous bioavailability is around 64%; oral bioavailability is very low). In the model on this page, a 5 mg vial is mixed with 2.5 mL of bacteriostatic water to give 2 mg/mL, or 20 mcg per insulin-syringe unit. Draw the water slowly down the vial wall, swirl gently until clear (do not shake), and refrigerate. At that concentration 100 mcg = 5 units, 150 mcg = 7.5 units, and 200 mcg = 10 units on a U-100 syringe. Inject on an empty stomach, away from dietary fat, and rotate sites.
Can Hexarelin be stacked with other peptides?expand_more
In research practice hexarelin (a GHS-R1a/GHRP agonist) is sometimes paired with a GHRH analogue such as CJC-1295 or sermorelin, because the two act on complementary pathways and can produce a larger combined GH pulse than either alone. However, there is no validated stacking protocol and no controlled human safety data for such combinations; layering compounds that elevate GH/IGF-1 can compound water retention, joint aches, and reductions in insulin sensitivity, and hexarelin's tendency to raise cortisol and prolactin at higher doses adds further risk. Treat any combination as experimental.
Related Guides & Tools
Step-by-step references for reconstituting, measuring, and storing Hexarelin, plus the universal dosing calculator.
Academic References & Study Citations
Ghigo E, Arvat E, Gianotti L, et al. 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. View Scientific Paper →
Imbimbo BP, Mant T, Edwards M, et al. Growth hormone-releasing activity of hexarelin in humans. A dose-response study. Eur J Clin Pharmacol. 1994;46(5):421-425. View Scientific Paper →
Roumi M, Marleau S, du Souich P, Maggi T, Deghenghi R, Ong H. Kinetics and disposition of hexarelin, a peptidic growth hormone secretagogue, in rats. Drug Metab Dispos. 2000;28(1):44-50. View Scientific Paper →
Rahim A, O'Neill PA, Shalet SM. Growth hormone status during long-term hexarelin therapy. J Clin Endocrinol Metab. 1998;83(5):1644-1649. View Scientific Paper →
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(1):77-84. View Scientific Paper →
Bodart V, Febbraio M, Demers A, et al. CD36 mediates the cardiovascular action of growth hormone-releasing peptides in the heart. Circ Res. 2002;90(8):844-849. View Scientific Paper →
Mao Y, Tokudome T, Kishimoto I. The cardiovascular action of hexarelin. J Geriatr Cardiol. 2014;11(3):253-258. View Scientific Paper →
Examorelin (hexarelin) — synthetic growth hormone secretagogue; sequence, pharmacology and Phase II development for GH deficiency. Reference overview. View Scientific Paper →