Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| Semax | TB-500 (Thymosin Beta-4) | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 200-600 mcg daily via intranasal administration (0.1% solution, 2-3 drops per nostril). | Research indicates 2-2.5 mg administered twice weekly via subcutaneous injection. |
| Timing | Morning and early afternoon dosing (avoid evening — may cause stimulation/insomnia). Intranasal preferred for rapid CNS delivery. | No strict timing requirements. Can be administered at any time of day. Systemic action means injection location is not critical. |
| Cycle Duration | 10-14 day cycles with equal rest periods. Some protocols use 3-5 day on / 2 day off patterns. | Loading phase: 4-6 weeks. Total cycle: 8-16 weeks. |
| Evidence Level | moderate_human | animal_plus_anecdotal |
Semax (Met-Glu-His-Phe-Pro-Gly-Pro) is a synthetic heptapeptide analog of the ACTH(4-10) fragment that rapidly upregulates brain-derived neurotrophic factor (BDNF) and its signaling receptor TrkB in the hippocampus (1.4-fold BDNF protein increase, 3-fold exon III BDNF mRNA increase). It activates dopaminergic and serotonergic brain systems, enhances neurotrophin gene expression (BDNF, NGF), and modulates intracellular calcium dynamics in brain neurons. Semax lacks ACTH's corticotropic activity, acting purely as a nootropic/neuroprotective agent.
Research indicates 200-600 mcg daily via intranasal administration (0.1% solution, 2-3 drops per nostril).
Morning and early afternoon dosing (avoid evening — may cause stimulation/insomnia). Intranasal preferred for rapid CNS delivery.
10-14 day cycles with equal rest periods. Some protocols use 3-5 day on / 2 day off patterns.
TB-500 is a synthetic fragment of Thymosin Beta-4, a 43-amino acid protein that sequesters G-actin monomers, preventing premature polymerization and facilitating cellular migration and morphological changes essential for wound healing. It upregulates actin to promote cell migration, proliferation, and differentiation of stem/progenitor cells at injury sites. TB-500 also enhances angiogenesis, reduces inflammation, and promotes tissue remodeling through increased re-epithelialization and vascular density.
Research indicates 2-2.5 mg administered twice weekly via subcutaneous injection.
No strict timing requirements. Can be administered at any time of day. Systemic action means injection location is not critical.
Loading phase: 4-6 weeks. Total cycle: 8-16 weeks.
Take our free assessment to get personalized recommendations based on your health goals, current stack, and biomarkers.
Get Your Free Protocol →or take the assessment →