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ToolsCompareSemaglutide vs Pentapeptide-18

Semaglutide vs Pentapeptide-18

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

GLP-1 / Weight Loss Agonists
Semaglutide
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Semaglutide is an FDA-approved GLP-1 receptor agonist originally developed for type 2 diabetes that has proven remarkably effective for weight loss. Clinical trials show average 15–20% body weight reduction. It is marketed as Ozempic (diabetes) and Wegovy (weight management).
Pentapeptide-18 (Leuphasyl) is a synthetic pentapeptide that mimics the sequence of enkephalin, an endogenous neuropeptide. It acts on neuronal pain receptors in facial muscles to reduce muscle contraction intensity and depth of expression lines, functioning similarly to Argireline (Acetyl Hexapeptide-3) but via a different receptor mechanism.
Half-Life
~7 days
Not applicable (topical)
Admin Route
SubQ, Oral
Topical
Research
Typical Dose
0.25 mg → 0.5 mg → 1 mg → 1.7 mg → 2.4 mg
0.005–0.05% in formulation
Frequency
Once weekly, subcutaneous
Twice daily
Key Benefits
  • Average 15–20% body weight reduction in clinical trials (STEP trials)
  • Significant reduction in appetite and food cravings
  • Improvement in blood sugar control and insulin sensitivity
  • Reduces cardiovascular risk (SELECT trial: 20% reduction in MACE)
  • May reduce risk of kidney disease
  • Improves metabolic markers (cholesterol, blood pressure)
  • FDA-approved — extensively studied with robust safety data
  • Weekly dosing convenience
  • Reduces depth of expression lines (forehead, crow's feet, glabellar)
  • Inhibits acetylcholine release for muscle-relaxing effect
  • Complementary mechanism to Argireline for enhanced anti-wrinkle activity
  • Reversible and well-tolerated
  • No risk of systemic paralysis at cosmetic concentrations
  • Suitable for daily use in serums and creams
Side Effects
  • Nausea (most common, especially during titration)
  • Vomiting
  • Diarrhea or constipation
  • Abdominal discomfort
  • +4 more
  • Generally very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
Stacks With