Retatrutide vs Somatropin (HGH)
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss Agonists
RetatrutideGrowth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)- 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.
- 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.
- Half-Life
- ~10–12 days
- 2-3 hours (subcutaneous); 20-30 minutes (intravenous)
- Admin Route
- SubQ
- Subcutaneous, Intramuscular (less common)
- Research
- —
- —
- Typical Dose
- 0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
- 0.15-0.3 mg/day (adults); titrated to IGF-1 levels
- Frequency
- Once weekly
- Once daily
- 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
- 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
- Side Effects
- Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
- Diarrhea
- Constipation
- Heart rate increase (from glucagon receptor agonism)
- +2 more
- Fluid retention and edema (common, dose-dependent)
- Carpal tunnel syndrome
- Joint and muscle pain
- Insulin resistance and elevated blood glucose
- +3 more
- Stacks With
- —
- —