Hexarelin
The biggest growth hormone pulse a peptide can give, for two to four weeks. Then it fades, and it costs you cortisol and prolactin.
What it is
Hexarelin fires the biggest growth hormone pulse of any peptide in its class, which makes it a short, hard push for recovery or the end of a cut. It is not a cycle you run for months: your pituitary stops answering after a few weeks, and it nudges cortisol and prolactin more than the gentler options.
This is for someone who has already run ipamorelin or a CJC blend, knows how growth hormone peptides feel, and wants a brief, forceful push: two to four weeks of harder recovery during a brutal training block, the last stretch of a cut, or coming back from a layoff. It is not a first growth hormone peptide, it is not a sleep aid, and it is not for anyone who cares about prolactin or cortisol staying put. If you want a steady, long-run GH peptide, this is the wrong tool.
You feel this one. Within half an hour of the shot there is often a flush and warmth, sometimes a mild hunger, and that night sleep is heavier. Recovery between sessions feels noticeably better inside the first week, and water comes on fast: puffier face, a tighter ring, tingly hands by day five to ten. Then the key event: somewhere in weeks three to four the effect fades. The sleep gets lighter, the recovery edge dulls. That is receptor desensitization, not a bad vial, and it is the cue to stop, not to raise the dose.
Dose 100 mcg subQ (just under the skin with an insulin needle), fasted, once a day, or twice a day with at least four to eight hours between for the harder version; 50 mcg is a fine first week. Run it two to four weeks, stop when the sleep and recovery gains fade, then take about four weeks off so your pituitary answers again. More than 150 to 200 mcg per shot buys almost no extra growth hormone and clearly more cortisol and prolactin, so there is no top tier above 100 twice daily. Keep food, especially carbs and fat, an hour away from each shot. A 5 mg vial is 50 shots at 100 mcg: a full four weeks once a day, or about three and a half weeks at twice a day. The mistakes: running it for months, chasing 200 mcg shots, and not noticing that libido dropped or nipples got tender, which is the prolactin talking.
The human evidence for the growth hormone pulse is clear: hexarelin gives one of the largest GH pulses of the class in human studies, about twice what the same dose of GHRH gives, and the fade with repeated dosing is also documented in people. Beyond that it is thin. There is early animal and small human work on the heart (it binds a receptor in heart tissue and protected heart muscle after injury in animals) and on bone, which is interesting and not a reason anyone should run it. No trial has looked at body composition or recovery in healthy adults. Not approved, and banned in tested sport.
Most people are better served elsewhere. For a longer, cleaner run with the same mechanism, ipamorelin keeps cortisol and prolactin quiet and does not fade; CJC-1295 + Ipamorelin is the standard pairing. For a stronger but still runnable GHRP, GHRP-2 sits between the two. Skip hexarelin entirely if you have blood pressure or heart issues, any cancer history, or if your prolactin already runs high.
What people use it for
Growth hormone release
Some evidenceHuman studies show hexarelin produces a larger growth hormone pulse than GHRP-6 and GHRP-2 at matched doses, and that response shrinks with repeated dosing over weeks. This is the best-documented thing it does. Whether the pulse turns into muscle or fat loss has not been measured in anyone.
Heart and bone
Early daysHexarelin binds a receptor on heart muscle (CD36) and protected heart tissue after injury in animal studies, with a small amount of human work on heart function and early animal data on bone density. This is mechanistic research, not a treatment, and it is not a reason to run it.
Fading response
Some evidenceThe drop in growth hormone response after two to four weeks of daily hexarelin is documented in human studies, more clearly than for any other GHRP. In practice it sets a hard limit on cycle length and makes raising the dose to compensate pointless.
How people use it
Safety, in brief
Things people sometimes notice
- A flush, warmth, or mild headache in the half hour after a shot
- Water retention within the first week: puffy face, tight ring, tingling hands
- A moderate hunger bump an hour after dosing, less than GHRP-6
- Heavier sleep and daytime sleepiness in the first week
The full picture — stop signs and who should talk to a doctor first — is on the dosing guide.
Sources
The labels and studies behind this page. Each link opens the original on PubMed, DailyMed or ClinicalTrials.gov.