Hexarelin: Reference Overview and Reconstitution Notes

Hexarelin is a man-made hexapeptide (a short chain of six amino acids, which are the building blocks of proteins) in the growth hormone secretagogue class. A secretagogue is simply a substance that prompts the release of another substance. Hexarelin works by binding to the ghrelin receptor. It is not approved by the FDA for any use and is banned in competitive sports under the WADA Prohibited List.

Hexarelin

What it is

Hexarelin (also called examorelin) is a synthetic hexapeptide, meaning it is a man-made chain of six amino acids. It belongs to the growth hormone secretagogue (GHS) family. Hexarelin acts as an agonist at the ghrelin receptor (GHS-R1a). An agonist is a molecule that activates a receptor, much like a key turning a lock. It is part of the growth hormone-releasing peptides (GHRPs), a group that also includes GHRP-2 and GHRP-6.

Research context and categorization

Growth Hormone Stimulation

Hexarelin falls under the growth hormone secretagogue category. In research settings, it is studied for its ability to trigger pulsatile (burst-like) releases of growth hormone from the anterior pituitary. The anterior pituitary is a small gland at the base of the brain that controls many hormone signals. Hexarelin does this through a pathway that is separate from the one used by growth hormone-releasing hormone.

Cardiovascular Investigation

Hexarelin is also studied in connection with heart and cardiovascular (heart and blood vessel) tissue. Researchers have found binding sites for growth hormone secretagogues in the heart. Some of the effects observed there appear to happen independently of growth hormone itself.

Regulatory Status

It is important to be clear that hexarelin is not FDA-approved. Any uses described in the scientific literature are investigational, meaning they are still being studied and have not been confirmed or approved. What is described here reflects what the compound is studied for, not established benefits.

Status

Key point: Hexarelin is an unapproved investigational compound that is strictly prohibited at all times in competitive sports under the WADA Prohibited List.

• Regulatory status: Research only. Hexarelin is not FDA-approved for any use and has no marketing approval in the major regions that have been reviewed.
• Sport status: Banned under the WADA Prohibited List. It falls under class S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics), specifically among the growth hormone-releasing peptides. It is banned at all times, both in and out of competition.

Reconstitution notes (general)

Hexarelin is supplied as a lyophilized (freeze-dried) powder. Think of it like instant coffee crystals: you add liquid to turn it back into a usable solution. That process is called reconstitution. Concentration is simply the amount of peptide divided by the amount of liquid added.

For example, 5 mg in 2 mL gives 2.5 mg/mL, and 5 mg in 2.5 mL gives 2 mg/mL. Use the reconstitution calculator at peptide calculator to find the right concentration for your vial and water volume.

Dilution and handling notes (compound-specific)

Reconstitution Ratios

Hexarelin is most commonly found in 2 mg and 5 mg vials. Typical amounts of bacteriostatic water added range from about 1 mL to 2.5 mL per vial.

A 1:1 ratio of water to peptide (for example, 2 mL of water for a 2 mg vial, giving 1 mg/mL) is a common starting point because the math stays simple and the solution remains stable.

Choosing how much water to add is a trade-off. Less water creates a more concentrated solution and a smaller volume to draw up. More water spreads the same amount of peptide across more markings on the syringe, making small measurements easier to read.

Mixing and Solubility

Hexarelin is easy to work with at the bench. It dissolves into a clear, colorless solution and does not typically gel, cloud, or form particles at the concentrations noted above. No acidic co-solvent is normally needed.

The standard approach is to let the vial warm to room temperature first. Then run the bacteriostatic water slowly down the inside wall of the vial instead of shooting it straight onto the powder. Swirl gently in a circular motion.

Avoid vigorous shaking. Hard shaking creates foam, which traps peptide inside it, makes accurate volume measurement difficult, and can stress the material. Give it a couple of minutes and a few gentle swirls to finish dissolving.

If the solution does not go fully clear, or shows cloudiness, particles, or discoloration, discard it rather than trying to force it into solution. As with any fine freeze-dried powder, minimize dust when opening a fresh vial, keep it away from direct light, and avoid repeated freeze-thaw cycles.

Handling and storage

When storing and handling reconstituted hexarelin, follow these guidelines:

• Store the reconstituted solution in a refrigerator at 2 to 8 degrees Celsius and keep it away from light.
• Wipe the stopper with an alcohol swab before each puncture.
• Label the vial with the date it was mixed and use it within about four weeks when kept refrigerated.
• Discard any solution that turns cloudy or discolored or develops floating particles.

Related reading

• Humanin
• IGF-1 LR3
• IGF-DES
• How Reconstitution Works
• How Long Does a Reconstituted Vial Last?

Tools and supplies

• peptide calculator
• Bacteriostatic Water 30 ml
• Gansulin Metal Reusable Pen
• 3 ml Glass Cartridges (10-pack)
• Complete Starter Kit

Reminder: research and educational reference only. Preppin Peppers sells hardware and materials, not peptides. Not medical, dosing, or health advice, not evaluated by the FDA, and not intended for human or animal use.

Frequently asked questions

What receptor does hexarelin bind to?

Hexarelin acts as an agonist at the ghrelin receptor (GHS-R1a), activating it the way a key turns a lock. It belongs to the GHRP subgroup alongside GHRP-2 and GHRP-6.

Is hexarelin banned in competitive sports?

Yes. Hexarelin is prohibited at all times under the WADA Prohibited List, class S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics), both in and out of competition.

How do you reconstitute a hexarelin vial for laboratory use?

Add bacteriostatic water to the lyophilized powder, e.g., 2 mL into a 5 mg vial yields 2.5 mg/mL. Use a reconstitution calculator to confirm the water volume for your target concentration.

What the research community gets wrong about hexarelin

Hexarelin shows up in a lot of bench discussions, and a few ideas about it get repeated even though the literature tells a more careful story. Here are points worth keeping straight when you label and handle a vial.

• It is not the same as ghrelin. Hexarelin is a synthetic six amino acid peptide (PubChem CID 6918297). Natural ghrelin is a different, larger molecule. Both bind the same receptor (GHS-R1a), but they are not interchangeable materials on your bench.
• The GHRPs are not one interchangeable group. Hexarelin, GHRP-2, and GHRP-6 are separate compounds with different molecular weights. A reconstitution ratio that gives a tidy concentration for one will not give the same concentration for another, so recheck the math per compound.
• "Growth hormone secretagogue" does not describe everything it does. Published work reports binding sites for these compounds in heart tissue and interactions with the CD36 receptor that appear separate from growth hormone. Filing it under growth hormone alone leaves out part of what the literature studies.
• The receptor response is not steady over time. In vitro work has shown rapid desensitisation of the receptor to hexarelin within a few minutes of the first dose. If you compare readings taken minutes apart in an assay, that timing can change the result on its own.
• Clear and dissolved does not mean it keeps forever. Hexarelin goes into a clear solution easily, which can make it feel more stable than it is. Cold storage, light protection, and a dated label still matter, and cloudiness or particles means discard.

From our bench: When you reconstitute a hexarelin vial, tell us how it behaved for you. Roughly how long, in gentle swirls or minutes, did the powder take to go fully clear at your chosen water volume, and did you see any foam, cloudiness, or particles before it settled? Real notes on time to clear and appearance help other researchers know what a normal prep looks like at the bench.

Sources

1. Bacteriostatic Water for Injection, USP , FDA/DailyMed label (0.9% benzyl alcohol)
2. Duerkop et al., Biotechnol J 2018 , Impact of Cavitation, High Shear Stress and Air/Liquid Interfaces on Protein Aggregation
3. Sigma-Aldrich (Merck) , Handling and Storage Guidelines for Peptides and Proteins
4. PubChem, Hexarelin (CID 6918297): molecular formula and growth hormone secretagogue classification
5. Orkin et al., J Endocrinol Invest 2003, Rapid desensitisation of the GH secretagogue (ghrelin) receptor to hexarelin in vitro (PubMed)
6. Mao et al., Endocrine 2015, Implications of ghrelin and hexarelin in diabetes and diabetes-associated heart diseases (PubMed)