Side-by-side comparison of mechanisms, dosing, interactions, and stacking potential.
| DSIP (Delta Sleep-Inducing Peptide) | Selank | |
|---|---|---|
| Category | Peptides | Peptides |
| Standard Dose | Research indicates 100-300 mcg administered before bedtime via subcutaneous injection or intranasal. | Research indicates 250-500 mcg daily via intranasal administration (0.15% solution, 2-3 drops per nostril). |
| Timing | 30-60 minutes before desired sleep onset. Evening only. | Can be dosed morning through evening. Unlike Semax, Selank is calming and can be used at night. |
| Cycle Duration | 2-4 week cycles with equal rest periods to prevent tolerance. | 14-21 day cycles with equal rest periods. |
| Evidence Level | animal_plus_anecdotal | moderate_human |
DSIP is a naturally occurring nonapeptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) originally isolated from rabbit brain hypothalamus in 1977. It modulates GABAergic neurotransmission by potentiating GABA-activated currents in hippocampal and cerebellar neurons while blocking NMDA-activated potentiation in cortical neurons. It also interacts with opioid-associated receptors, modulates serotonin and dopamine systems (increasing serotonin levels), and promotes delta wave (slow-wave) sleep through mechanisms that remain incompletely characterized.
Research indicates 100-300 mcg administered before bedtime via subcutaneous injection or intranasal.
30-60 minutes before desired sleep onset. Evening only.
2-4 week cycles with equal rest periods to prevent tolerance.
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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