Retatrutide vs GHK
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss Agonists
RetatrutideSkin & CosmeticAnti-Aging & Longevity
GHK- Summary
- Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
- 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
- ~10–12 days
- Extremely short as free peptide; tissue binding extends local effects
- Admin Route
- SubQ
- SubQ, Topical, Oral
- Research
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- Typical Dose
- 0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
- 100–500 mcg
- Frequency
- Once weekly
- Daily or 5x per week
- Key Benefits
- ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
- Superior to both semaglutide and tirzepatide in early trial comparisons
- Triple receptor mechanism addresses multiple obesity pathways
- Significant reduction in liver fat (MASH/NAFLD indication being studied)
- Improved cardiovascular and metabolic markers
- Once-weekly dosing
- Potential for greatest weight loss of any currently investigated compound
- 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
- Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
- Diarrhea
- Constipation
- Heart rate increase (from glucagon receptor agonism)
- +2 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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