Semax vs Selank half-life
Semax has an elimination half-life of about 6 min; Selank has about 6 min. Both were developed in Russia as intranasal neuropeptides. Semax is derived from ACTH (4-10) and Selank from tuftsin. Both are degraded within minutes in blood.
Side by side
| Semax | Selank | |
|---|---|---|
| Half-life | 6 min | 6 min |
| Route | Intranasal / SC | Intranasal / SC |
| Category | Nootropic & neuro | Nootropic & neuro |
| Evidence | Limited | Limited |
| Remaining after 24 hours | <0.01% | <0.01% |
| Remaining after 7 days | <0.01% | <0.01% |
| ~97% cleared (5 half-lives) | 30 min | 30 min |
| Steady state (4-5 half-lives) | 24 min to 30 min | 24 min to 30 min |
Single-dose decay
Share of one dose remaining over time, assuming first-order elimination. Dashed lines mark each half-life.
Semax (t½ 6 min) Selank (t½ 6 min)
Semax: Rodent data: minutes in plasma; effects outlast plasma levels. Selank: Rodent data: minutes in plasma; effects outlast plasma levels.
FAQ
Which lasts longer, Semax or Selank?
Semax and Selank have similar half-lives: about 6 min and 6 min.
How long do Semax and Selank stay in your system?
With first-order elimination, about 97% of a single dose is cleared after five half-lives: roughly 30 min for Semax and 30 min for Selank. Individual clearance varies.
How long until Semax and Selank reach steady state?
With consistent repeated dosing, levels approach steady state after 4 to 5 half-lives: about 24 min to 30 min for Semax, and 24 min to 30 min for Selank.
How reliable are these half-lives?
Semax: Limited evidence. Selank: Limited evidence. Anecdotal values are community estimates and may be far off.