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ToolsCompareGlutathione vs Pentapeptide-18

Glutathione vs Pentapeptide-18

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

Anti-Aging & LongevityImmune Support
Glutathione
Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Summary
Glutathione is the body's master endogenous antioxidant tripeptide, composed of glutamate, cysteine, and glycine. It neutralizes reactive oxygen species, supports detoxification in the liver, recycles other antioxidants (vitamins C and E), and plays a central role in immune function, DNA repair, and cellular redox balance.
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
Minutes to hours depending on route; IV half-life approximately 10-30 minutes
Not applicable (topical)
Admin Route
Oral (liposomal preferred), Sublingual, Intravenous, Nebulized/inhaled, Topical
Topical
Research
Typical Dose
250-1000 mg per day
0.005–0.05% in formulation
Frequency
Once or twice daily
Twice daily
Key Benefits
  • Primary endogenous antioxidant and free radical scavenger
  • Supports hepatic detoxification of xenobiotics and heavy metals
  • Recycles vitamins C and E to maintain antioxidant network
  • Modulates immune function and T-cell activity
  • Skin brightening via inhibition of tyrosinase (IV/topical routes)
  • Neuroprotective in oxidative stress-related conditions
  • Mitochondrial protection and energy metabolism support
  • 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
  • Oral bioavailability is limited (largely hydrolyzed in gut); liposomal or sublingual forms preferred
  • IV administration: rare allergic reactions, vein irritation
  • High-dose supplementation may cause zinc depletion over time
  • Inhaled glutathione may trigger bronchoconstriction in asthmatics
  • 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