Hexarelin

GH Secretagogue (GHS-R1a agonist)

Also known as: EP 23905 · MF-6003

The most potent GH-releasing hexapeptide. Produces the highest GH peak of any GHRP but desensitizes faster & elevates cortisol/prolactin significantly.

Typical Dose

100–200 mcg per injection, 1–2x daily

Route

Subcutaneous injection

Cycle

4–8 weeks on, 4+ weeks off (mandatory due to desensitization)

Half-life

~30–60 minutes

Storage

Reconstituted: 2–8°C, use within 30 days.

Overview

Hexarelin is a synthetic hexapeptide analog of GHRP-6 with a single amino acid substitution that substantially increases GH-releasing potency. At equivalent doses it produces higher GH peaks than GHRP-2 or GHRP-6 but at the cost of faster pituitary desensitization (downregulation of GHS-R1a with repeated dosing) & greater cortisol & prolactin elevation.

Hexarelin is typically used in shorter cycles (4–8 weeks) with extended off periods to prevent receptor desensitization. It has independent cardioprotective properties mediated through the CD36 receptor (distinct from GHS-R1a), which has been studied for cardiac repair applications independent of GH release.

Quick Start Guide

Reconstitute with 2 mL bacteriostatic water per 2 mg vial.

Start at 100 mcg subcutaneously. Higher doses (150–200 mcg) produce plateauing GH output with higher side effect burden.

Use for 4–6 weeks only; take 4+ weeks off to allow GHS-R1a to resensitize.

Research Indications

Maximal GH pulse (short burst)

Most Effective

Highest GH peak of any GHRP. Reserved for short-cycle use where maximal GH output is the priority.

Cardiac protection (CD36 mechanism)

Moderate

Hexarelin binds CD36 on cardiomyocytes & coronary artery cells independently of GH release. Animal studies show reduced ischemia-reperfusion injury.

Research Protocols

Short-cycle GH maximization

4–6 weeks only; then 4-week break

Dose

100 mcg + 100 mcg CJC-1295 (no DAC)

Frequency

2x daily (AM fasted + pre-sleep)

Route

SubQ abdomen

Peptide Interactions

CJC-1295 (no DAC)Synergistic

GHRH amplifies GHS-R1a pulse. Hexarelin + GHRH remains synergistic even at elevated desensitization.

IpamorelinCompatible

Do not stack two GHRPs. Use Hexarelin when maximal GH peak is the goal; switch to Ipamorelin for long-term use.

Side Effects & Safety

Common

Significant cortisol elevation (most pronounced of all GHRPs)
Prolactin elevation
Water retention
Fatigue
Flushing

Uncommon

Decreased libido (prolactin effect with long use)
Headache
Receptor desensitization (GH blunting with continued use)

When to Stop

Signs of significant prolactin elevation (galactorrhea, sexual dysfunction)
Known malignancy
Signs of allergic reaction

How to Reconstitute

Wipe stopper.

2 mL bacteriostatic water per 2 mg vial.

Inject down inner wall. Swirl gently.

Refrigerate.

Dosing math: 1000 mcg/mL with 2 mL BAC water. For 100 mcg: 0.1 mL.

Quality Indicators

Good — use as normal

Clear, colorless solution

Acceptable

Minor cloudiness immediately clearing

Discard immediately

Persistent cloudiness
Particulate
Discoloration

What to Expect

Week 1–2

Highest GH peaks of any GHRP. Water retention & strength gains begin quickly.

Week 3–6

GH peak begins to blunt due to GHS-R1a desensitization. Discontinue by week 6–8.

Week 7–10 (off)

Allow receptor resensitization before restarting. Maintain gains through nutrition.

Community Insights

Self-reported. Reflects user experience, not clinical outcomes.

Research References

Hexarelin, a new growth hormone-releasing peptide, is active after oral administration in humans

Journal of Endocrinology · 1994

Original human characterization of Hexarelin showing potent GH release & confirming superiority over GHRP-6 in peak response.

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Information on this page applies to pharmaceutical-grade peptides. Purity & identity of research-grade products vary. Certipep provides independent ESI-TOF-MS & HPLC analysis with a signed analytical report.

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