GHRP-6

GHRP-6 is a ghrelin-receptor (GHS-R1a) agonist. It was built by trial and error from enkephalin fragments; its receptor was cloned in 1996 and the natural ligand, ghrelin, was found in 1999. It stimulates GH directly at the pituitary and through the hypothalamus, and in people it also stimulates ACTH and cortisol and provokes hunger.

Sequence: His-D-Trp-Ala-Trp-D-Phe-Lys-NH₂A hexapeptide with two D-amino acids, so no one-letter form applies.

One claim per card, each with its own tier and source. Tiers 1 and 2 are human data. Tiers 3 and 4 are not yet.

• Raised overnight GH, ACTH and cortisol and increased stage 2 sleep in healthy men (placebo-controlled).

  T2Clinical
  [1]Frieboes et al., 1995 (Neuroendocrinology)(opens in a new tab)

• Given orally to short-statured children, produced a GH response comparable to intravenous GHRH.

  T2Clinical
  [2]Bellone et al., 1995 (Eur J Endocrinol)(opens in a new tab)

• Acts at the ghrelin receptor; its discovery led to the identification of GHS-R and of ghrelin itself.

  T3Preclinical
  [3]Bowers, 2001 (J Clin Endocrinol Metab review)(opens in a new tab)

1. [1]Frieboes et al., 1995 (Neuroendocrinology) (opens in a new tab)
2. [2]Bellone et al., 1995 (Eur J Endocrinol) (opens in a new tab)
3. [3]Bowers, 2001 (J Clin Endocrinol Metab review) (opens in a new tab)

• IpamorelinT2Clinical

  Ghrelin-receptor / GH secretagogue

  The selective GH pulse without the cortisol baggage.

  2 of 4 claims human-tested · 3 references · Research-only

• HexarelinT2Clinical

  Ghrelin-receptor / GH secretagogue

  The potent secretagogue with a heart story that never left the lab.

  2 of 3 claims human-tested · 3 references · Research-only

• GHRP-2T2Clinical

  Ghrelin-receptor / GH secretagogue

  The GH-releasing peptide that became a diagnostic test in Japan.

  2 of 2 claims human-tested · 2 references · Approved abroad

Compare every growth hormone axis peptide side by side