Ipamorelin is a short man-made peptide of five amino acids that nudges the pituitary gland to release growth hormone. Researchers value it for its selectivity: it barely raises stress hormones.
5 aa: Aib-His-D-2-Nal-D-Phe-Lys-NH₂. Synthetic GHRP. Aib = α-aminoisobutyric acid (protection against DPP-IV). ~711 Da.
The most selective GH secretagogue: stimulates GH without a significant rise in cortisol, ACTH, or prolactin (unlike GHRP-2 and GHRP-6). Phase II RCT (n=117, 2014): well tolerated in postoperative ileus. The classic partner of Mod-GRF.
GHS-R1a on somatotrophs → ↑IP₃/DAG → ↑intracellular Ca²⁺ → exocytosis of GH granules. At the same time ↓somatostatin → potentiation. The most selective GHRP: minimal effect on ACTH/cortisol (9849822: even a ×200 dose did not ↑cortisol).
Studies used 200-300 mcg SC 1-3 times/day (morning, post-workout, bedtime) for a course of 3-6 months; in combination with Mod-GRF, both peptides were administered at the same time.
Level A-B Human clinical trials. There are randomized controlled trials (RCTs), or the compound has been approved by a regulatory agency. The most reliable level. Phase II human RCT. Extensive preclinical data.
⚠️ Not FDA-approved as a standalone drug. Banned by WADA (S2). Less desensitization than GHRP-6/hexarelin. Research only.
Research peptides are laboratory reagents (Research Use Only). They are not medicines and are not intended for use in humans or animals.