Somatropin (HGH) vs GHK
Side-by-side comparison of key properties, dosing, and research.
Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)Skin & CosmeticAnti-Aging & Longevity
GHK- Summary
- Somatropin is recombinant human growth hormone (rhGH), identical in structure to the 191-amino acid pituitary-derived growth hormone. It is FDA-approved for growth hormone deficiency, short stature, and wasting conditions. Off-label, it is widely explored for body composition, anti-aging, and performance enhancement, though significant risks accompany unsupervised use.
- 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
- 2-3 hours (subcutaneous); 20-30 minutes (intravenous)
- Extremely short as free peptide; tissue binding extends local effects
- Admin Route
- Subcutaneous, Intramuscular (less common)
- SubQ, Topical, Oral
- Research
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- Typical Dose
- 0.15-0.3 mg/day (adults); titrated to IGF-1 levels
- 100–500 mcg
- Frequency
- Once daily
- Daily or 5x per week
- Key Benefits
- Increases lean muscle mass and reduces body fat (particularly visceral)
- Restores growth hormone deficiency (FDA-approved)
- Improves bone mineral density
- Enhances exercise capacity and recovery
- Supports skin thickness and collagen synthesis
- Improves lipid profile in GHD patients
- Explored for anti-aging and cellular regeneration
- 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
- Fluid retention and edema (common, dose-dependent)
- Carpal tunnel syndrome
- Joint and muscle pain
- Insulin resistance and elevated blood glucose
- +3 more
- Excellent safety profile (naturally occurring peptide)
- Rare: mild injection site reaction (SC)
- No significant adverse effects identified in research
- Stacks With
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