P21 vs Semax

Overview

P21 and Semax are both studied in the peptide research space.

P21: A hexapeptide (Ac-DGGLAG-NH2) derived from ciliary neurotrophic factor (CNTF) that is claimed to mimic BDNF effects and promote neurogenesis.

Semax: A synthetic heptapeptide analogue of ACTH(4-7) with a C-terminal Pro-Gly-Pro extension, developed by Russian researchers and approved in Russia since ~1997 for stroke, cognitive impairment, and optic nerve disorders.

Evidence Comparison

Aspect	P21	Semax
Evidence Level	Very Low	Moderate
Human Studies	0	8
Preclinical Studies	15	24
Total Sources	15	32

Key Differences

Aspect	P21	Semax
Category	Cognitive	Cognitive
Evidence Strength	Very Low	Moderate
Total Sources	15	32
Human Studies	0	8

Summary

• P21: Very Low evidence with 15 total sources (0 human)
• Semax: Moderate evidence with 32 total sources (8 human)

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This comparison is for educational purposes only and is not medical advice. Consult a healthcare professional before making any decisions about peptide use.