hGHRH(1-40)OH vs Modified GRF(1-29)

Head-to-head comparison of hGHRH(1-40)OH (Human growth hormone-releasing factor (1-40) hydroxyl) and Modified GRF(1-29) ([D-Ala2, Nle27]-human growth hormone-releasing hormone (1-29) amide) — benefits, dosing, side effects, research data, and where to buy.

PropertyhGHRH(1-40)OHModified GRF(1-29)
CategoryGrowth HormoneGrowth Hormone
Full NameHuman growth hormone-releasing factor (1-40) hydroxyl[D-Ala2, Nle27]-human growth hormone-releasing hormone (1-29) amide
Molecular WeightN/AN/A
Half-Life5-20 minutes10-30 minutes
Amino Acids4029
Typical Dose1-2 mcg/kg50-300 mcg
RouteSubcutaneous/IVSubcutaneous
Purity≥98%≥98%
Studies Count85150
Research StatusClinical ResearchInvestigational

hGHRH(1-40)OH Benefits

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

Modified GRF(1-29) Benefits

  • enhanced GH release
  • greater peptide stability
  • IGF-1 support research
  • longer receptor engagement

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

Modified GRF(1-29) Dosing

50-100 mcg SC for acute GH-response studies|100-300 mcg SC in monitored research protocols|repeat dosing in short investigative cycles with GH/IGF-1 tracking

hGHRH(1-40)OH Side Effects

  • flushing
  • headache
  • lightheadedness

Modified GRF(1-29) Side Effects

  • headache
  • water retention
  • injection-site irritation

Research Overview

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.

Modified GRF(1-29)

Modified GRF(1-29) has been studied as a practical GHRH analog for boosting GH release while improving peptide stability versus the native fragment. It is a standard reference compound in experimental work on growth hormone pulsatility and analog design.

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Common Stacking Partners

hGHRH(1-40)OH stacks with:

L-arginineL-ornithineglycine

Modified GRF(1-29) stacks with:

L-arginineL-ornithineglycine
ghrhfragmentpituitaryresearch-peptideghrh-analogsynthetic-peptidegrowth-hormoneresearch-compound