Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| LL-37 (Cathelicidin) | Selank | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 50-100 mcg daily via subcutaneous injection for immune support. | Research indicates 250-500 mcg daily via intranasal administration (0.15% solution, 2-3 drops per nostril). |
| Timing | Morning administration preferred for immune support. Topical application directly to wound sites. | Can be dosed morning through evening. Unlike Semax, Selank is calming and can be used at night. |
| Cycle Duration | 4-8 week cycles. Short-term use preferred due to limited long-term safety data. | 14-21 day cycles with equal rest periods. |
| Evidence Level | animal_plus_anecdotal | moderate_human |
LL-37 is a 37-residue amphipathic helical antimicrobial peptide, the only human cathelicidin, that kills bacteria by forming tetrameric channels that perforate cytoplasmic membranes. Beyond direct antimicrobial activity, it modulates innate immunity through formyl-peptide receptor 2 (FPR2), induces chemotaxis of neutrophils and monocytes, upregulates CXCR4 and IL-8, and neutralizes bacterial endotoxins (LPS). It also promotes wound healing through keratinocyte migration and angiogenesis.
Research indicates 50-100 mcg daily via subcutaneous injection for immune support.
Morning administration preferred for immune support. Topical application directly to wound sites.
4-8 week cycles. Short-term use preferred due to limited long-term safety data.
Selank (Thr-Lys-Pro-Arg-Pro-Gly-Pro) is a synthetic heptapeptide analog of the immunomodulatory peptide tuftsin (from IgG heavy chain) with a Pro-Gly-Pro extension for metabolic stability. It allosterically modulates GABA-A receptors, enhancing GABA binding and GABAergic neurotransmission. Selank modifies mRNA levels of 84 genes involved in GABAergic neurotransmission in the frontal cortex, enhances enkephalinase inhibition (increasing endogenous enkephalin levels), and modulates serotonergic and noradrenergic systems to produce anxiolytic and nootropic effects.
Research indicates 250-500 mcg daily via intranasal administration (0.15% solution, 2-3 drops per nostril).
Can be dosed morning through evening. Unlike Semax, Selank is calming and can be used at night.
14-21 day cycles with equal rest periods.
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