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Hexarelin

Growth hormone releasing peptide · No brand name. Sometimes written Examorelin

UK status
Unlicensed medicine
Availability
Research use only
Evidence base
Early human studies, never approved
Controlled drug
No

Sequence

A hexapeptide of the GHRP family.

The short version

What it does

Sold to raise your own growth hormone, for muscle and recovery. It belongs to the generation of peptides that ipamorelin was designed to improve on.

How it does it

Presses the same button on the pituitary gland as ipamorelin does, prompting a growth hormone release. It is less fussy about which other buttons it presses at the same time.

The catch

Two specific problems. It also raises cortisol, your main stress hormone, which works against what people take it for. And the response fades with repeated use, so it stops working.

Everything below goes into the detail, with sources.

Hexarelin is worth a record because it shows what the newer growth hormone peptides were trying to fix. It works, in the narrow sense that it raises growth hormone. It also raises cortisol, and it stops working, and those two facts explain the entire direction of travel in this class.

At a glance

Compound type
Peptide, 6 amino acids
Drug class
Growth hormone releasing peptide, GHRP family
Family relatives
GHRP-2, GHRP-6, and ipamorelin
Route
Injection under the skin
Marketed for
Muscle, recovery, heart tissue protection
Known limitation
Desensitisation. The response falls with repeated use.
Also raises
Cortisol and prolactin, unlike ipamorelin
UK status
Unlicensed medicine. Supply for human use prohibited.
In sport
Named on the WADA Prohibited List, S2.2.4. Prohibited at all times.

01What it is

The growth hormone releasing peptides, GHRPs, are a family of small synthetic peptides that trigger growth hormone release through the ghrelin receptor. GHRP-6 came first, then GHRP-2, then hexarelin, and each was an attempt at more effect with fewer side effects.

Ipamorelin was the end point of that effort: selective for growth hormone release without appreciably raising cortisol or prolactin. Hexarelin is what came before, and the difference is the whole reason ipamorelin was developed.

02How it came about

Hexarelin was studied from the early 1990s, including in humans, both as a growth hormone secretagogue and separately for possible effects on heart tissue. It never reached approval for any indication.

It persists in grey-market selling, usually among people who want a cheaper alternative to ipamorelin or who have read about the cardiac research.

Legal position

No MHRA authorisation. Supplying it for human use in the UK is prohibited under the Human Medicines Regulations 2012. Not a controlled drug. Sold as a research chemical.

Athletes: WADA names hexarelin explicitly under S2.2.4, among growth hormone releasing peptides, alongside GHRP-1, GHRP-2, GHRP-4, GHRP-5 and GHRP-6. Prohibited at all times.

04How it works

It binds the growth hormone secretagogue receptor on the pituitary, prompting growth hormone release. Unlike ipamorelin it also stimulates release of cortisol and prolactin, because it is less selective across the receptor's downstream effects.

Why the cortisol matters

Cortisol is catabolic: it breaks tissue down. Raising it alongside growth hormone works against the muscle and recovery effects people are taking the compound for. It is not a minor side effect, it is arguably self-defeating.

Separately, hexarelin shows marked desensitisation: the growth hormone response falls with repeated administration, apparently through receptor downregulation. A compound that stops working the more you use it is a poor basis for anything.

05What it is not

Claims that attach themselves to this compound and do not hold up.

  • Not an approved medicine anywhere.
  • Not a selective growth hormone secretagogue. It raises cortisol and prolactin too.
  • Not reliable over time. Desensitisation is well described for this compound.
  • Not a proven cardioprotective agent. There is interesting animal and early human research on heart tissue, and no clinical programme that concluded anything.

06What the evidence shows

Early human studies confirm it raises growth hormone. There is also a genuinely interesting body of research on effects on cardiac tissue, independent of growth hormone, which attracted attention and never became a drug.

Interesting is not the same as established

The cardiac research is the part most often cited by sellers, and it is mostly animal work and small early human studies. No completed clinical programme supports any cardiac use, and nobody should be self-administering an unlicensed peptide for a heart problem.

There is no controlled human trial evidence for the muscle, recovery or body composition claims made for it.

What is not known

Long-term safety, any established dose, and whether the desensitisation can be avoided. Effects of chronically raised cortisol alongside growth hormone are not characterised.

07Reported harms

No regulated frequency table. Effects consistent with the pharmacology would include those of raised cortisol and prolactin, water retention, effects on glucose handling, and increased appetite through ghrelin receptor activity.

Standard unregulated supply risks apply in full.

08Interactions and cautions

No interaction data. Raised cortisol matters for anyone on corticosteroids or with adrenal problems, and the glucose effects matter for anyone on diabetes medication. Nobody can quantify either for this compound.

09Stopping

Growth hormone, cortisol and prolactin return to baseline. Nothing else documented.

10Monitoring

Nothing formal exists. Given the pharmacology, cortisol and prolactin would be the markers worth watching, which is not something any seller mentions.

11Questions worth asking

Take these to a doctor or pharmacist. A good clinician will not mind being asked, and the answers are specific to you in a way nothing on this page can be.

  1. Do I know this raises cortisol, which works against what I want from it?
  2. Do I understand the response fades with repeated use?
  3. Have I ever actually been tested for growth hormone deficiency?

12Common questions

How is hexarelin different from ipamorelin?

Both act on the same receptor to release growth hormone. Hexarelin also raises cortisol and prolactin, and shows marked desensitisation with repeated use. Ipamorelin was specifically developed to avoid both problems.

Does hexarelin protect the heart?

There is genuinely interesting animal and early human research on cardiac tissue effects, independent of growth hormone. No completed clinical programme supports a cardiac use, and nobody should be treating a heart condition with an unlicensed peptide.

Why does it stop working?

Desensitisation. Repeated exposure appears to downregulate the receptor, so the growth hormone response falls. It is well described for this compound and is one reason development moved on.

Is it banned in sport?

Yes. WADA names hexarelin explicitly among the growth hormone releasing peptides, prohibited at all times, in and out of competition.

13Sources

Links go to the authoritative source. Where a document sits behind a paywall or moves around, the full citation is given so you can find it yourself.

  1. Prohibited List, S2.2.4 growth hormone releasing peptidesWADA
  2. Hexarelin human studiesPubMed
  3. Hexarelin and cardiac tissue researchPubMed
  4. Ipamorelin record/compounds/ipamorelin/
  5. Unlicensed medicines guidanceMHRA

14Change history

Every substantive change to this record is logged here with its date. Corrections are made openly, not quietly.

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