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ToolsCompareGHK vs Leuprolide

GHK vs Leuprolide

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

Skin & CosmeticAnti-Aging & Longevity
GHK
Sexual Health & Libido
Leuprolide
Summary
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.
Leuprolide is a synthetic GnRH superagonist that, with continuous administration, paradoxically suppresses LH and FSH through receptor desensitization — the opposite effect of pulsatile GnRH. Used medically for prostate cancer, endometriosis, and precocious puberty. In men's health, short-duration use for PCT and testosterone suppression rebound.
Half-Life
Extremely short as free peptide; tissue binding extends local effects
~3 hours (SC/IM), but depot formulations last 1–12 months
Admin Route
SubQ, Topical, Oral
SubQ, IM
Research
Typical Dose
100–500 mcg
7.5 mg monthly, 22.5 mg 3-monthly, or 45 mg 6-monthly
Frequency
Daily or 5x per week
Per depot schedule
Key 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
  • Medical: reduces testosterone in prostate cancer
  • Medical: suppresses estrogen in endometriosis and uterine fibroids
  • Medical: delays precocious puberty
  • Research: testosterone rebound effect after short course
  • Transgender care: hormone suppression in adolescents
  • Research: hormonal re-sensitization protocols
Side Effects
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
  • Hot flashes (with testosterone suppression)
  • Decreased libido and erectile dysfunction
  • Initial testosterone flare (first 1–2 weeks)
  • Bone density loss with long-term use
  • +3 more
Stacks With