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Hexarelin: What the Evidence Actually Shows

Grade CNo US approval

The short version

A synthetic hexapeptide secretagogue, among the most potent in its class.
Raises cortisol and prolactin substantially, more than ipamorelin.
Desensitisation is well documented. Response drops with continued use.
Has been studied for cardiac effects independent of growth hormone.
No US approval.

The tolerance problem

This is the detail that matters most and gets left out. Hexarelin produces a large initial growth hormone release, and that response attenuates with continued administration, in some studies substantially within weeks. Whatever your view of the underlying idea, a compound whose effect fades while its cortisol effect does not is a poor trade.

The cortisol issue

Hexarelin stimulates ACTH and cortisol alongside growth hormone. For most people using secretagogues, the goals are recovery, sleep and body composition, all of which chronic cortisol elevation works directly against. This is the pharmacological reason more selective compounds were developed.

The cardiac research

One genuinely interesting thread: hexarelin appears to have cardioprotective effects in animal models that are independent of growth hormone, acting through CD36. That work is real but preclinical, and it is not the reason anyone buys it.

What this will not do

It will not keep working at the same intensity. Desensitisation is expected.
It will not act selectively. Cortisol and prolactin come with it.
It will not be legally available.

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