Thymosin Alpha-1 vs Pentapeptide-18
Side-by-side comparison of key properties, dosing, and research.
Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18- Summary
- Thymosin Alpha-1 is a naturally occurring 28-amino acid peptide derived from the thymus gland. It is a powerful immune modulator approved in many countries for treating chronic hepatitis B, hepatitis C, and as an adjunct in cancer immunotherapy.
- 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
- 2–3 hours
- Not applicable (topical)
- Admin Route
- SubQ
- Topical
- Research
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- Typical Dose
- 0.8–1.6 mg
- 0.005–0.05% in formulation
- Frequency
- Twice weekly
- Twice daily
- Key Benefits
- Enhances T-cell and NK cell activity
- Supports recovery from viral and bacterial infections
- May reduce inflammation systemically
- Supports healthy aging and immune resilience
- Improves vaccine response
- Supports liver health
- May help with chronic fatigue syndrome and post-viral conditions
- Approved in multiple countries for hepatitis B and C treatment
- 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 irritation
- Mild flu-like symptoms initially (immune activation)
- Fatigue (rare)
- 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
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