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ToolsCompareThymosin 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
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