Adverse effect · Hexarelin

How common is safety in humans with Hexarelin?

C
Grade C — weak human evidenceEarly-phase · effect size: small · adverse
Short answerWeak human evidence. Early-phase: enough to be interesting, not enough to count on. Where an effect is seen it is a small effect. Short-term dosing is generally well tolerated in the small studies; transient flushing and mild cortisol/prolactin rises are described. No long-term safety data.

What the studies show

Short-term dosing is generally well tolerated in the small studies; transient flushing and mild cortisol/prolactin rises are described. No long-term safety data.

A few small or poorly-controlled human studies. Enough to be interesting; not enough to count on. Most of what gets called “clinically proven” online lives here.

  1. 1
    Rahim A, et al. Growth hormone status during long-term hexarelin therapy.J Clin Endocrinol Metab, 1998;83:1644–164916 weeks; GH response attenuates, IGF-1 and body composition unchanged.

In context

Hexarelin is a synthetic six-amino-acid growth-hormone-releasing peptide. Single doses cause a strong, well-documented growth-hormone spike in humans, but the one study of continued use showed the response fades within weeks and that IGF-1 and body composition did not meaningfully change. It was never developed into an approved medicine, and the muscle, fat-loss and cardiac claims made for it have no controlled human evidence.

Hexarelin is not approved. Legal status differs by country — see the regulation section or the jurisdiction pages.

Questions

Is Hexarelin proven to cause safety in humans?
No. The human evidence is weak (Early-phase); LYO grades it C.
What studies are behind the grade?
Short-term dosing is generally well tolerated in the small studies; transient flushing and mild cortisol/prolactin rises are described. No long-term safety data.
Is Hexarelin approved for this?
No. Hexarelin is not approved; it is not an approved medicine for any indication in the jurisdictions LYO covers.

Other outcomes for Hexarelin

Written and maintained by LYO Research — how pages are written and checked. Reviewed 3 September 2026. Grades count human evidence only; see how LYO grades. Not medical advice. Correct this page →