hGHRH(1-37)OH vs hGHRH(1-40)OH

Head-to-head comparison of hGHRH(1-37)OH (Human growth hormone-releasing factor (1-37) hydroxyl) and hGHRH(1-40)OH (Human growth hormone-releasing factor (1-40) hydroxyl) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyhGHRH(1-37)OHhGHRH(1-40)OH
CategoryGrowth HormoneGrowth Hormone
Full NameHuman growth hormone-releasing factor (1-37) hydroxylHuman growth hormone-releasing factor (1-40) hydroxyl
Molecular WeightN/AN/A
Half-Life5-20 minutes5-20 minutes
Amino Acids3740
Typical Dose1-2 mcg/kg1-2 mcg/kg
RouteSubcutaneous/IVSubcutaneous/IV
Purity≥98%≥98%
Studies Count6085
Research StatusClinical ResearchClinical Research

hGHRH(1-37)OH Benefits

  • GH release studies
  • minimal-sequence mapping
  • receptor pharmacology
  • peptide stability research

hGHRH(1-40)OH Benefits

  • GH secretion research
  • fragment-activity comparison
  • receptor binding studies
  • axis physiology modeling

hGHRH(1-37)OH Dosing

1-2 mcg/kg SC or IV bolus|acute stimulation with serial GH assays|short-course research administration with biomarker monitoring

hGHRH(1-40)OH Dosing

1-2 mcg/kg SC or IV in acute research settings|single-bolus GH stimulation protocols|repeated low-dose administration in comparative studies

hGHRH(1-37)OH Side Effects

  • flushing
  • headache
  • transient fatigue

hGHRH(1-40)OH Side Effects

  • flushing
  • headache
  • lightheadedness

Research Overview

hGHRH(1-37)OH

Human GHRF(1-37)OH has appeared in studies examining how loss of C-terminal residues affects biological activity at the GHRH receptor. It is often used alongside other fragments to define structure-activity relationships within the GHRH family.

hGHRH(1-40)OH

Human GHRF(1-40)OH has been studied to understand how truncation of the native hormone changes biological potency and half-life. It is a common research tool for mapping minimal active sequences within the GHRH family.

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Common Stacking Partners

hGHRH(1-37)OH stacks with:

L-arginineL-lysineglycine

hGHRH(1-40)OH stacks with:

L-arginineL-ornithineglycine
ghrhfragmentstructure-activityendocrinologypituitaryresearch-peptide