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ToolsCompareHexarelin vs GHK

Hexarelin vs GHK

Side-by-side comparison of key properties, dosing, and research.

Growth Hormone Peptides
Hexarelin
Skin & CosmeticAnti-Aging & Longevity
GHK
Summary
Hexarelin is a potent synthetic GHRP and the strongest GH secretagogue in its class per unit dose. It also exhibits unique cardioprotective properties through direct binding to cardiac CD36 receptors, independent of GH release. Its potency is balanced by a tendency to desensitize GH release with prolonged use, making cycling important.
GHK is the natural tripeptide (Gly-His-Lys) released from human albumin that activates tissue remodeling, collagen synthesis, and anti-aging gene expression. The copper-free form is the biological signaling molecule; it chelates copper in tissue to form GHK-Cu but also has independent biological activity.
Half-Life
~70 minutes
Extremely short as free peptide; tissue binding extends local effects
Admin Route
SubQ
SubQ, Topical, Oral
Research
Typical Dose
100–200 mcg
100–500 mcg
Frequency
2–3 times daily
Daily or 5x per week
Key Benefits
  • Strongest GH pulse per mcg among GHRPs
  • Unique direct cardioprotective effects via CD36
  • Increased IGF-1 and muscle anabolism
  • Accelerated recovery from training
  • Bone density support
  • Anti-aging via GH axis
  • Potential cardiac rehabilitation benefits
  • Stimulates collagen and extracellular matrix synthesis
  • Activates tissue repair gene expression programs
  • Anti-aging: reverses 57% of age-related gene changes
  • Antioxidant and anti-inflammatory
  • Wound healing and skin barrier repair
  • Improves skin laxity, texture, and radiance
  • Neuroprotective (stimulates NGF, BDNF)
  • Anti-fibrotic in liver and lung models
Side Effects
  • Water retention
  • Elevated cortisol
  • Elevated prolactin (more pronounced than other GHRPs)
  • Receptor desensitization with continuous use
  • +1 more
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
Stacks With