P21 vs Thymalin
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
P21
P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.
Full details →Thymalin
Thymalin is a polypeptide preparation derived from calf thymus. Developed in Russia, it has been used for decades to support immune function and has shown potential anti-aging effects in long-term studies.
Full details →Side-by-Side Comparison
| Aspect | P21 | Thymalin |
|---|---|---|
| Mechanism | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. | Regulates the ratio of T-cell subpopulations, stimulates cellular immunity, and enhances phagocytosis. Also affects neuroendocrine regulation and may influence melatonin production. |
| Typical Dosage | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. | Clinical protocols: 5-20mg daily intramuscularly for 3-10 days. Often cycled 1-2 times per year for maintenance. |
| Administration | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. | Intramuscular injection. Usually administered in short courses rather than continuously. Often combined with Epithalamin for anti-aging protocols. |
| Side Effects | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. | Generally well-tolerated. May cause injection site reactions or temporary flu-like symptoms as immune function is modulated. |
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