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ToolsCompareGHK vs Semax

GHK vs Semax

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

Skin & CosmeticAnti-Aging & Longevity
GHK
Cognitive Enhancement
Semax
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.
Semax is a synthetic heptapeptide derived from ACTH developed in Russia. It is a potent nootropic that enhances memory, focus, and provides neuroprotection. Approved in Russia for cognitive disorders, stroke recovery, and traumatic brain injury.
Half-Life
Extremely short as free peptide; tissue binding extends local effects
Minutes (but effects persist for hours via BDNF induction)
Admin Route
SubQ, Topical, Oral
Intranasal, SubQ
Research
Typical Dose
100–500 mcg
0.25–1 mg (250–1000 mcg)
Frequency
Daily or 5x per week
1–2 times daily
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
  • Enhances memory and learning
  • Improves focus and concentration
  • Increases mental energy and motivation
  • Provides neuroprotection via BDNF and NGF upregulation
  • Reduces cognitive decline
  • May alleviate ADHD symptoms
  • Supports recovery from brain injury and stroke
  • Fast-acting — effects within 30–60 minutes
  • Approved in Russia for cognitive disorders and stroke recovery
Side Effects
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
  • Headache (rare, often from higher doses)
  • Anxiety or overstimulation at high doses
  • Sleep disruption if dosed too late
  • Irritability (uncommon)
Stacks With