Understand the source comparison
Hexarelin for Growth Hormone Release: Secretagogue Comparison
Hexarelin Ghrelin receptor (GHS-R1a) agonist at pituitary somatotrophs 7–15× baseline, peak at 20–30 min Moderate (prolactin and cortisol elevation at high doses) Subcutaneous or IV injection Highest potency among GHRPs; produces consistent, robust GH pulses i
No winner is assigned.
This page preserves a source comparison for education. It does not add a rating, recommendation or clinical judgment.
- Hexarelin
- Ghrelin receptor (GHS-R1a) agonist at pituitary somatotrophs
- 7–15× baseline, peak at 20–30 min
- Moderate (prolactin and cortisol elevation at high doses)
- Subcutaneous or IV injection
- Highest potency among GHRPs; produces consistent, robust GH pulses independent of somatostatin tone; preferred for acute GH secretion studies
- GHRP-2
- Ghrelin receptor agonist
- 5–10× baseline
- Moderate (similar side effect profile to hexarelin)
- 40–50% less potent than hexarelin at equivalent doses; still effective but requires higher dosing for comparable GH release
- GHRP-6
- 4–7× baseline
- Low (stimulates appetite significantly via ghrelin pathways)
- Lowest potency in the GHRP class; strong appetite stimulation limits utility in metabolic studies
- Ipamorelin
- Selective ghrelin receptor agonist
- 4–6× baseline
- High (minimal prolactin/cortisol effects)
- Subcutaneous injection
- Selective profile reduces off-target effects; lower potency than hexarelin but cleaner pharmacology for chronic dosing models
- Sermorelin (GHRH 1-29)
- GHRH receptor agonist at pituitary
- 3–6× baseline (variable, somatostatin-dependent)
- High (pure GHRH pathway)
- Requires intact hypothalamic-pituitary axis; blunted by somatostatin; synergistic when combined with ghrelin agonists
- CJC-1295
- GHRH receptor agonist with extended half-life
- 2–4× baseline sustained over days
- High
- Produces sustained baseline elevation rather than acute pulses; useful for chronic GH elevation models
- MK-677 (Ibutamoren)
- Oral ghrelin receptor agonist
- 2–3× baseline sustained
- Moderate
- Oral administration
- Convenient dosing; lower peak amplitude but sustained elevation; increases baseline GH and IGF-1 without discrete pulses