Hexarelin
A simple guide to one of the strongest growth-hormone-releasing peptides studied so far — what it does, what the science says, and what we still don’t know.
Based on emerging research. These findings are promising but require further validation.
Hexarelin is a synthetic peptide that tells your pituitary gland to release more growth hormone. It is one of the most potent compounds in its class. Research also suggests it may protect heart tissue. It is not FDA-approved and is available only as a research chemical.
Hexarelin is a man-made peptide — a short chain of six amino acids. Scientists created it in the 1990s to study growth hormone release. Its full chemical name is His-D-2-methyl-Trp-Ala-Trp-D-Phe-Lys-NH₂.
It belongs to a family called GHRPs (growth-hormone-releasing peptides). Other members include GHRP-2, GHRP-6, and ipamorelin. Among these, hexarelin causes the strongest burst of growth hormone in studies.
Hexarelin is given by injection under the skin. It is not a steroid or a hormone itself — it is a signal that tells your body to make more of its own growth hormone.
Your brain has a receptor called GHS-R1a (the “ghrelin receptor”). Hexarelin plugs into this receptor and triggers your pituitary gland to release a pulse of growth hormone into your blood.
Unlike the hormone ghrelin, hexarelin does not make you very hungry. It also acts on a second receptor called CD36, which sits on heart muscle cells. This is why researchers have studied hexarelin for possible heart-protective effects, separate from its growth hormone action.
The growth hormone spike from a single hexarelin dose typically peaks within 15–30 minutes and returns to baseline within 2–4 hours. With repeated daily use over several weeks, the response gets smaller — a process called desensitization.
Growth Hormone Release
In healthy adults, a single subcutaneous dose of hexarelin (1–2 mcg/kg) raised peak growth hormone levels by roughly 5–20 fold in multiple clinical studies. The response was dose-dependent and larger than other GHRPs at the same dose. After about 4–16 weeks of daily use, the GH response decreased but did not disappear entirely.
Heart Protection
Animal studies showed hexarelin reduced scar tissue after a heart attack and improved heart function in models of heart failure. These effects appear tied to CD36 signaling, not growth hormone. Small human studies in patients with heart failure also showed improved cardiac output, though large clinical trials have not been done.
Other Findings
Some studies noted modest effects on cortisol and prolactin levels (both rose slightly after dosing). Unlike GHRP-6, hexarelin does not appear to significantly raise appetite. Early research into bone density and lean body mass changes is limited and inconclusive.
Hexarelin has never been approved by the FDA for any medical use. It is not a controlled substance in the United States. It can be legally sold for laboratory research but cannot be marketed for human consumption.
As of May 2026, hexarelin is not on the FDA’s Category 2 restricted list (the list that blocked compounding of certain other peptides in 2024). However, its regulatory status could change. Check our regulatory tracker for live updates.
If you are thinking about hexarelin, bring these questions to a qualified healthcare provider:
- Is my IGF-1 or growth hormone level actually low? What does my bloodwork say?
- Would an FDA-approved growth hormone therapy be a better option for me?
- How would hexarelin interact with my current medications?
- What monitoring (blood tests, imaging) would I need while using it?
- What are the risks for someone with my health history?
- Are there compounding pharmacies in my area that you trust?
There is still a lot we don’t know about hexarelin. Key gaps in the research include:
- No large, long-term human safety trials exist.
- The heart-protective effects seen in animals have not been confirmed in controlled human trials.
- Optimal cycling schedules to avoid desensitization are not established.
- Interactions with other GH secretagogues or hormonal therapies are poorly studied.
- Effects in women have barely been researched — most studies used male subjects.
Want more detail?
Read the technical analysis
An in-depth technical breakdown of the research on Hexarelin.
Frequently Asked Questions
What is hexarelin used for?
Hexarelin is a research peptide studied for its ability to trigger growth hormone release. It has also been investigated for cardioprotective effects. It is not approved by the FDA for any medical use.
Is hexarelin the same as GHRP-6?
No. Both are growth-hormone-releasing peptides, but hexarelin binds more strongly to the ghrelin receptor and does not increase appetite as much as GHRP-6. Their side-effect profiles also differ.
Does hexarelin stop working over time?
Studies show the growth hormone response to hexarelin decreases with repeated use over several weeks. Researchers call this desensitization. Cycling protocols are often discussed to manage this effect.
What are the most common side effects?
In clinical studies, the most commonly reported side effects were mild — flushing, dizziness, and brief increases in cortisol and prolactin. Serious side effects were rare at standard research doses.
Is hexarelin legal to buy?
In the United States, hexarelin is not FDA-approved and is not a controlled substance. It can be sold as a research chemical but cannot be marketed for human consumption. Rules vary by country.
How is hexarelin different from CJC-1295 or ipamorelin?
CJC-1295 acts on a different receptor (GHRH-R) and increases growth hormone through a separate pathway. Ipamorelin is another GHRP but is more selective with fewer effects on cortisol and prolactin. Hexarelin is the most potent GHRP at stimulating GH release.
Ghigo E et al. “Growth hormone-releasing activity of hexarelin, a new synthetic hexapeptide, after intravenous, subcutaneous, intranasal, and oral administration.” J Clin Endocrinol Metab. 1994;78(3):693–698.
Broglio F et al. “Effects of acute hexarelin administration on cardiac performance in patients with coronary artery disease.” Eur J Pharmacol. 2002;448(2-3):193–200.
Locatelli V, Bhechini S. “Growth hormone secretagogues: focus on the growth hormone-releasing peptides.” Pharmacol Res. 1999;39(3):165–172.
Muccioli G et al. “Growth hormone-releasing peptides and the cardiovascular system.” Ann Endocrinol (Paris). 2000;61(1):27–31.
Ong H et al. “Discovery of a CD36-binding peptide, hexarelin, with cardioprotective activities.” Cardiovasc Drug Rev. 2006;24(1):18–32.