Delta sleep-inducing peptide (DSIP) is one of the older molecules in the research-peptide catalogue, and one of the most frequently over-sold. It is marketed today for sleep, recovery and stress, yet the published human record behind it is small, largely from the 1980s, and decidedly mixed. This article documents what studies have actually investigated, separating human clinical work from animal research and from the unverified protocols that circulate online. Nothing here is guidance; it is a description of the literature. PepSource supplies DSIP strictly as a research reagent.
What DSIP is
DSIP is a naturally occurring nonapeptide with the amino-acid sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu and a molecular weight of roughly 849 daltons. It was first isolated from the cerebral venous blood of rabbits during induced sleep in the 1970s by the Swiss researchers Monnier and Schoenenberger, which is where its name comes from. In regulatory documents it appears under the name emideltide.
Despite roughly half a century of study, DSIP has no single, well-characterised receptor, and its mechanism of action remains unresolved. That matters for interpreting the literature: without an agreed target, much of the research is observational rather than mechanistic, and effects reported in one setting have often failed to replicate in another.
Human clinical data: what trials investigated
Sleep and insomnia
The best-known human work dates from the 1980s, when Schneider-Helmert, Schoenenberger and colleagues investigated DSIP in patients with chronic insomnia. A detail routinely lost in modern marketing is the route: these studies administered DSIP by slow intravenous infusion, commonly reported at around 25 nmol/kg, not by the nasal sprays or subcutaneous injections sold today. Some early open studies described normalised sleep after a short series of infusions, but later placebo-controlled work found the objective effects on sleep architecture to be modest and inconsistent, and some authors concluded the changes could not be reliably separated from placebo. Reported protocols and outcomes varied between studies.
Withdrawal syndromes
A second, smaller body of human work investigated DSIP in alcohol and opioid withdrawal, again mostly in the 1980s. These reports described reductions in withdrawal symptoms following administration, with occasional headaches noted. The studies were small, largely open-label, and have not been followed by modern controlled replication.
Taken together, the human literature is thin. It is old, the sample sizes are small, the administration route in the controlled trials differs from what is marketed now, and the two areas with any human signal, insomnia and withdrawal, are exactly the two where the effect sizes were most disputed.
Animal and preclinical work
Most DSIP research is preclinical. In animal models the peptide has been investigated for effects on sleep and EEG activity, stress resistance, thermoregulation, seizure thresholds and oxidative-stress markers, and several groups have reported stress-protective, so-called adaptogenic effects. These findings are biologically interesting, but they do not translate into conclusions about humans and should not be read as evidence of any effect in people.
Unverified online protocols
A great deal of what is written about DSIP "dosing" online has no basis in the controlled literature. Vendor pages and forums typically describe low-microgram amounts given subcutaneously or intranasally before sleep, a route and quantity that do not correspond to the intravenous protocols used in the published trials. These figures are not supported by human clinical evidence, are not standardised, and are mentioned here only to be labelled clearly for what they are: unverified. PepSource does not provide administration protocols, and none should be inferred from this article.
Regulatory status: where accuracy matters
DSIP is not an approved medicine in the United Kingdom, the United States or, to our knowledge, anywhere else. Under its regulatory name emideltide it was placed on the FDA's Category 2 list of bulk drug substances, substances that may not be used in compounding, in 2023.
In July 2026 the FDA's Pharmacy Compounding Advisory Committee reviewed seven peptides, including emideltide (DSIP), for possible addition to the 503A bulk-substances list. Emideltide was the only one of the seven the committee voted against recommending. It is worth being precise about what this means, because competitors frequently are not: an advisory-committee vote is non-binding, it is not FDA approval, and it does not change the law. In DSIP's case the committee did not even recommend it. We set out the wider decision in our explainer on the July 2026 compounding vote.
Summary of the evidence
| Research area | Type of evidence | What studies investigated or found |
|---|---|---|
| Chronic insomnia | Human, 1980s, small; mostly intravenous | Modest, inconsistent effects on sleep; some findings not separable from placebo |
| Alcohol and opioid withdrawal | Human, 1980s, small, largely open-label | Reported symptom reduction; occasional headaches; no modern replication |
| Sleep/EEG, stress, thermoregulation, seizures, oxidative stress | Animal/preclinical | Various reported effects; not translatable to humans |
| Online "dosing" protocols | Not clinical evidence | Low-microgram subcutaneous or intranasal figures; unverified, not derived from trials |
Research handling
Because DSIP is supplied as a lyophilised powder, reconstitution and cold-chain handling determine whether a reagent is usable; our note on reconstitution solvents covers the basics. Independent purity and identity data for our material are published on the lab results page, and the same compound is also catalogued as a DSIP nasal spray research format.
The honest summary is that DSIP has been studied for half a century and still lacks the kind of large, modern, controlled human trials that would settle what, if anything, it does. Where the literature is thin, saying so is more useful than filling the gap with confidence it has not earned.
Sources
- Graf MV, Kastin AJ. Delta-sleep-inducing peptide (DSIP): an update. Peptides, 1986 (PubMed 3550726)
- Schneider-Helmert D et al. Effects of DSIP on 24-hour sleep-wake behaviour in severe chronic insomnia (PubMed 3622582)
- DSIP in the treatment of withdrawal syndromes from alcohol and opiates (PubMed 6548969)
- Delta sleep-inducing peptide. European Journal of Anaesthesiology, 2001
- FDA Pharmacy Compounding Advisory Committee briefing document (2026)
- AJMC: FDA panel backs 6 peptides for compounding (emideltide not recommended)
Research use only. All products referenced are supplied strictly as research reagents for laboratory and in-vitro use, and are not for human or veterinary consumption.