GHK (Glycyl-L-Histidyl-L-Lysine)

Safety Profile

How It Works

Ghk is a tiny three-amino-acid peptide that your body naturally makes, found in blood, saliva, and urine. When you are young, you have plenty of it. By age 60, levels drop by about 60%. What makes GHK distinctive is that computational analysis suggests it affects over 4,000 genes, pushing them toward how they behaved when you were younger. It boosts collagen production, activates antioxidant defenses, reduces inflammation, helps remodel damaged tissue, and promotes blood vessel growth for better healing. When bound to copper (as GHK-Cu), it also delivers copper where cells need it for repair enzymes. The strongest real-world evidence is for skin applications: topical use at 1-2% concentration has shown improved skin thickness, firmness, elasticity, and wound healing in small human studies, though large-scale clinical trials are still limited.

Studied Dosages

4 dosing entries documented.

Studies

Tier 3 (Phase 2 RCT data or multiple smaller human studies). A completed small RCT demonstrated statistically significant skin thickness and density improvements with topical GHK-Cu (PMID 15931022). A Phase 2 RCT of topical GHK-Cu gel for acute wound healing is currently recruiting (NCT07437586). Multiple additional small human clinical studies (n=10-71) report skin improvements with topical GHK-Cu. However, important caveats apply: the clinical studies are predominantly small, often industry-affiliated, and not extensively independently replicated. Much foundational research comes from a small number of laboratories, particularly the work of Loren Pickart (GHK discoverer/patent holder). The gene expression modulation data (4,000+ genes) is computational analysis (Broad Institute cMap) rather than clinical trials (PMID 24704744). Systemic anti-aging effects from injectable GHK lack RCT data. The topical skin evidence base supports Tier 3; the systemic anti-aging claims are closer to Tier 4-5.

Legal Status

Not FDA-approved for any medical indication. FDA database searches return no approvals (Drugs@FDA), no drug labels, and no FAERS adverse event reports for GHK or GHK-Cu. Not a controlled substance under the Controlled Substances Act. Commercially treated as a cosmetic ingredient when used topically in OTC skincare products. Not nominated or designated on the 503A or 503B bulk drug substance lists for compounding. No new drug applications (NDAs) or biologics license applications (BLAs) have been approved.