Ipamorelin — Growth Hormone Secretagogue

What Is Ipamorelin?

Ipamorelin is a selective growth hormone secretagogue that stimulates GH release through the ghrelin/GHS receptor. It is considered one of the most selective GH-releasing peptides — primarily stimulating GH without significantly affecting cortisol, prolactin, or aldosterone, a notable advantage over GHRP-6 and GHRP-2.

Mechanism of Action

Ipamorelin acts as a ghrelin mimetic, binding to GHS-R in the pituitary gland and triggering calcium-dependent GH release. Unlike GHRP-6, it does not significantly stimulate appetite, and unlike GHRP-2, it has minimal effects on cortisol and prolactin. It is frequently combined with CJC-1295 (no DAC) for synergistic GH pulsing.

Key Research Findings

• GH release — Clinical studies confirm dose-dependent increases in plasma GH following SubQ injection
• Selectivity — GH release without concomitant cortisol, ACTH, or prolactin increases at therapeutic doses
• Bone density — Animal studies show increased bone mineral content and formation markers
• Body composition — Preclinical data suggests improved lean mass and reduced adiposity with CJC-1295
• Sleep quality — Anecdotal reports of improved deep sleep, consistent with GH's role in sleep architecture

Known Side Effects

Generally well-tolerated. Reported effects include transient headache, flushing, dizziness, and injection site reactions. Water retention and joint stiffness may occur with sustained use.

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