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Tools›Compare›Thymosin Beta-4 vs Semax

Thymosin Beta-4 vs Semax

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

Recovery & RepairAnti-Aging & Longevity
Thymosin Beta-4
Cognitive Enhancement
Semax
Summary
Thymosin Beta-4 is an endogenous 43-amino acid peptide that is the primary intracellular actin sequestering peptide. It promotes tissue repair, reduces inflammation, regenerates hair follicles, and protects cardiac tissue. Closely related to TB-500 (the active fragment), it is used for systemic tissue recovery and anti-aging.
Semax is a synthetic heptapeptide derived from ACTH developed in Russia. It is a potent nootropic that enhances memory, focus, and provides neuroprotection. Approved in Russia for cognitive disorders, stroke recovery, and traumatic brain injury.
Half-Life
Not well characterized; likely similar to TB-500 (~1–2 hours)
Minutes (but effects persist for hours via BDNF induction)
Admin Route
SubQ, IM
Intranasal, SubQ
Research
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Typical Dose
5–10 mg
0.25–1 mg (250–1000 mcg)
Frequency
2x per week (loading), then 1x per week (maintenance)
1–2 times daily
Key Benefits
  • Systemic tissue repair and regeneration
  • Promotes cardiac recovery after myocardial infarction
  • Hair follicle regeneration and anti-hair-loss
  • Anti-inflammatory (systemic)
  • Wound healing acceleration
  • Neuroprotection after brain injury
  • Protects against ischemia-reperfusion injury
  • Anti-aging at cellular level
  • Synergizes powerfully with BPC-157
  • Enhances memory and learning
  • Improves focus and concentration
  • Increases mental energy and motivation
  • Provides neuroprotection via BDNF and NGF upregulation
  • Reduces cognitive decline
  • May alleviate ADHD symptoms
  • Supports recovery from brain injury and stroke
  • Fast-acting — effects within 30–60 minutes
  • Approved in Russia for cognitive disorders and stroke recovery
Side Effects
  • Generally very well tolerated
  • Injection site reactions
  • Mild fatigue at initiation (repair signaling)
  • Rare: mild inflammatory response
  • +1 more
  • Headache (rare, often from higher doses)
  • Anxiety or overstimulation at high doses
  • Sleep disruption if dosed too late
  • Irritability (uncommon)
Stacks With
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