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ToolsCompareTesamorelin vs Pentapeptide-18

Tesamorelin vs Pentapeptide-18

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

Growth Hormone PeptidesFat Loss & Metabolic
Tesamorelin
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Tesamorelin is an FDA-approved synthetic GHRH analog specifically indicated for reduction of excess abdominal (visceral) fat in HIV patients with lipodystrophy. It is the only GHRH peptide with FDA approval for a fat-reduction indication and is studied off-label for metabolic syndrome and cognitive function.
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
~26 minutes
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
2 mg
0.005–0.05% in formulation
Frequency
Once daily
Twice daily
Key Benefits
  • FDA-approved for visceral fat reduction in HIV lipodystrophy
  • Significant reduction in trunk/visceral fat (average 15–20% in trials)
  • Improved triglyceride and lipid profiles
  • Potential cognitive benefits and memory improvement
  • Preserves lean mass while reducing fat
  • Natural pulsatile GH stimulation
  • 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
  • Injection site reactions (redness, irritation)
  • Arthralgia and joint pain
  • Peripheral edema
  • Carpal tunnel syndrome
  • +2 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