SLEEP & RECOVERY / MATRIX
DSIP and Selank, Side by Side
Where the two sleep-and-recovery peptides converge, where they diverge, and — most importantly — how far the evidence behind each one actually reaches.
The short version
This page lines up DSIP and Selank on the dimensions that matter most when reading research peptides: what kind of molecule each one is, where it has been studied most, how strong that evidence is, how it has been administered in studies, its regulatory standing, and its single biggest caution. The headline: both are studied for effects relevant to sleep, recovery, and anxiety, but they sit at different stages of mechanistic understanding. DSIP has no identified receptor after forty-plus years; Selank has two characterized pathways. DSIP has a thin and inconsistent human record; Selank has a narrow but more positive Russian clinical record. Neither is an FDA-approved medicine. Neither is presented here with a human dose.
The comparison matrix
| Dimension | DSIP | Selank |
|---|---|---|
| Peptide class | Endogenous nonapeptide (9 aa); INN Emideltide | Synthetic heptapeptide (7 aa); tuftsin analog |
| Most-studied in | Sleep regulation, HPA axis, stress response | Anxiety, GABAergic signaling, nootropic effects |
| Evidence base (model) | Rabbit EEG [6]; one 6-person human insomnia pilot [5]; small HPA study in men [4] | Rat anxiety/UCMS models [9][10]; human cytokine study [12]; gene-expression data [10] |
| Administration studied | IV (human studies) [4][5]; intraventricular (rabbit) [6]; intranasal (rat stroke) [7] | Intranasal (rodent, community) [11]; oral/IV implied in Russian clinical work [8] |
| Regulatory / WADA status | Not approved anywhere; no WADA specific listing (S0 catch-all may apply) | Russia-registered Rx anxiolytic; not FDA/EMA-approved; research chemical in the US |
| Key caution | No receptor identified; sleep evidence "extremely poorly documented and still weak" [2] | Single-region (Russian) evidence base; multi-system interaction unknowns [8] |
Peptide class
DSIP is a naturally occurring nonapeptide — nine amino acids, found in the brain, with an INN (Emideltide) that was registered but never used commercially. Selank is a fully synthetic heptapeptide — seven amino acids — engineered by extending the endogenous immune peptide tuftsin with a metabolic stabilizer. One is a molecule the body appears to make; the other is a designed optimization of a natural scaffold. Neither class confers approval or established safety [2][8].
Most-studied in
DSIP's research history centers on sleep physiology — specifically the enhancement of slow-wave, delta EEG activity [6] — and on HPA-axis modulation (ACTH suppression) [4]. The recovery angle includes a neuroprotection finding after stroke in rats [7] and a lifespan/tumor-suppression result in mice that comes from a small cluster of Russian studies [3]. Selank's research lives almost entirely in anxiety: animal models of chronic stress, GABAergic gene expression, enkephalin stabilization, and a human cytokine study in anxious patients [8][10][12]. The sleep connection for Selank is indirect — anxiety relief as a route to better sleep — while for DSIP it is the explicit founding claim.
Evidence base (model)
Neither compound has a convincing body of well-powered human trials. DSIP's best human data come from a 1981 single-session intravenous trial in six insomniacs [5] and a 1989 neuroendocrine study in men [4]. Both are small, old, and largely unreplicated. Selank's human-subject data are a single study of cytokine modulation in patients with anxiety-asthenic disorders [12], conducted in a supervised Russian clinical context. The deeper preclinical record for Selank — multiple mechanisms, gene-expression data, stress models — makes its evidence architecture more solid, but it shares with DSIP the same gap: no large, independent, randomized human trials [8].
Administration studied
DSIP's human studies used intravenous administration [4][5]; animal mechanistic work used intraventricular infusion (rabbit) and intranasal delivery (rat stroke) [6][7]. Selank has been studied intranasally in rodents [11] and by unspecified routes in Russian clinical work; community use is predominantly intranasal drops or spray [8]. Neither peptide has validated oral bioavailability data in humans, and both are small enough to degrade rapidly in biological fluids without targeted delivery.
Regulatory status
Neither peptide has FDA or EMA approval for any indication. DSIP has no approval from any major regulator; its INN (Emideltide) was registered but never resulted in a marketed product. WADA does not list it by name, but the catch-all S0 category for non-approved pharmacological agents may apply [2]. Selank is registered as a prescription anxiolytic in Russia and has been discussed in some neighboring markets; everywhere else it is an unregulated research chemical [8]. For anyone in competitive sport, both should be treated with caution under the S0 non-approved-substances rule.
Key caution
For DSIP, the defining problem is stated bluntly in its own literature: "an unresolved riddle" with sleep evidence that is "extremely poorly documented and still weak," no receptor, no gene, no precursor, and a dose-response that is parabolic and hard to predict [2]. It may do nothing — and for many people, it does. For Selank, the most important caution is geographic: the great majority of its clinical evidence originates from a small set of Russian research groups, with minimal independent Western replication [8]. Both compounds carry the further cautions common to all research-chemical peptides — unregulated supply, unknown long-term safety, and multi-system pharmacological activity that makes combination risks hard to assess. The lesson they share: promising signals in early or geographically narrow research do not translate automatically to predictable effects in unsupervised people.