Sermorelin & GHRP-2 & GHRP-6 vs P21
A detailed comparison to help you understand the differences and choose the right peptide for your research goals.
Sermorelin & GHRP-2 & GHRP-6
A powerful tri-blend combining Sermorelin (a GHRH analog) with two growth hormone releasing peptides. This combination produces significantly greater GH release than any single peptide, with studies showing up to 54-fold increases in pulsatile GH secretion.
Full details →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 →Side-by-Side Comparison
| Aspect | Sermorelin & GHRP-2 & GHRP-6 | P21 |
|---|---|---|
| Mechanism | Sermorelin stimulates the pituitary via GHRH receptors, while GHRP-2 and GHRP-6 act as ghrelin mimetics on different receptor subtypes. The combination creates synergistic GH release through multiple complementary pathways. GHRP-6 also strongly stimulates appetite. | Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity. |
| Typical Dosage | Typical protocols: Sermorelin 100-300mcg, GHRP-2 100-300mcg, GHRP-6 100-300mcg. Often administered 2-3 times daily, 30 minutes before meals or at bedtime. | Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks. |
| Administration | Subcutaneous injection. Best administered fasted or before sleep to maximize natural GH cycle. The three peptides can be mixed together or administered separately. | Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously. |
| Side Effects | Increased hunger (especially from GHRP-6), water retention, facial flushing, nausea, tingling, potential increases in cortisol and prolactin levels. | Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue. |
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