Delta Sleep-Inducing Peptide (DSIP)
Discovered in 1977, DSIP remains one of the most enigmatic peptides in neurobiology: described for nearly fifty years, it still has no identified receptor.
- Research Use Only
- Molecule under study
- Living document
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- Current research state
- A historically established molecule, studied since 1977; data are predominantly preclinical and exploratory.
- Current clinical phase
- No FDA/EMA approval — strictly for research use
- Last update
- 20 July 2026 · Reference fact sheet v1.0
- Living document
- Updated regularly as research progresses.
What is Delta Sleep-Inducing Peptide (DSIP)?
DSIP is a small protein, more precisely a nonapeptide (9 amino acids) with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu.
It was first isolated in 1977 by Schoenenberger and Monnier's team from the cerebral venous blood of rabbits in which deep sleep had been induced by electrical stimulation of the thalamus.
The initial idea was that a circulating factor could “transfer” the state of deep sleep from one animal to another. Fifty years later, the picture is more nuanced: DSIP does exist, but its exact role remains debated.
Names you may come across
This molecule may appear under several names in the scientific, clinical or technical literature. Here are the main designations you may come across.
The full official name in English, as used in the scientific literature.
The abbreviation most commonly used in publications.
The one-letter code for the 9 amino acids that make up the molecule.
Understanding it simply
A few simple analogies help explain DSIP.
An unexpected discovery
DSIP was isolated while investigating whether deep sleep left a chemical trace in the blood. A Swiss team identified this small protein in the 1970s.
A peptide, not a sleeping pill
DSIP does not act like a conventional sleeping pill. Its effect, when described, is more subtle and concerns sleep architecture (particularly deep sleep stages) rather than rapid sleep onset.
A mechanism that remains uncertain
Despite decades of research, no specific DSIP receptor has been clearly identified. The reported effects on sleep are inconsistent from one study to another, and their mode of action remains debated.
What research shows today
Science advances step by step. We clearly distinguish what is firmly established from what remains under study.
- The peptide's structure and initial discovery are well documented. — established
- Effects on sleep, the stress response and opioid modulation described in preclinical studies. — established
- A specific receptor has not been clearly identified to date. — ongoing
- Limited modern, large-scale clinical data. — ongoing
- No approval by any major regulatory agency. — ongoing
A molecule known for nearly fifty years, but whose precise mechanism and clinical effects remain only partially characterised: most data come from preclinical research and small clinical studies.
What the research shows
- The structure of DSIP (nonapeptide WAGGDASGE) has been well characterised since 1977.
- DSIP-like immunoreactivity has been reported in several tissues and biological fluids; however, no gene or precursor encoding DSIP has been identified, leaving its endogenous origin uncertain.
- Preclinical studies describe effects on sleep, the stress response, thermoregulation and possible opioid modulation, with results that vary between models.
What still remains to be studied
- The specific receptor for DSIP has not been identified to date; its precise mechanisms remain only partially characterised.
- Modern, large randomised clinical studies are few in number.
- No major regulatory agency has evaluated it for approval.
- Some initially reported effects (particularly in opioid withdrawal) were not confirmed in subsequent research.
What we know today
Not all information carries the same weight of evidence. We therefore present it across three clearly distinct levels, from the most solid to the most indicative.
What scientific publications show
Scientific evidence- DSIP is often described as an endogenous peptide, but this origin remains debated: immunoreactive substances have been detected, notably in the brain, without an identified gene or precursor.
- Preclinical studies suggest modulation of sleep architecture (deep sleep stages) and the stress response.
- A possible influence on opioid modulation and withdrawal has been explored, with conflicting results.
What some professionals report
Documented- Review authors emphasize that, despite having been known for many years, DSIP remains incompletely characterized.
- The publications reiterate the need for modern clinical studies before any conclusions can be drawn.
What the community reports
Field observations- Users report subjective improvements in sleep quality and depth.
- These observations vary from person to person and do not constitute scientific evidence.
Observations reported by the community do not constitute scientific evidence. DSIP remains incompletely characterized, making caution all the more essential.
How does Delta Sleep-Inducing Peptide (DSIP) work?
DSIP is a special case: it is a peptide that has been known for nearly fifty years, yet its specific receptor has not been formally identified to date.
- Sleep architecture
- Effects on deep sleep stages described in several preclinical studies.
- Stress axis
- Modulation of the hormonal stress response (hypothalamic–pituitary–adrenal axis) reported in preclinical research.
- Opioid system
- Interactions with the opioid system investigated in earlier research, with conflicting results.
- Specific receptor
- Not identified to date — this is one of the major limitations in the characterization of DSIP.
The lack of a clearly identified receptor is one reason why DSIP remains only partially characterized, despite having been known for many years.
Clinical trials timeline
A molecule under study progresses step by step. Here, simply, is where the research currently stands.
- Discovery· 1977Completed
Isolation of DSIP by Schoenenberger and Monnier
The peptide is isolated in Basel from the cerebral venous blood of rabbits in which deep sleep has been induced by electrical stimulation of the thalamus.
- Preclinical· 1980sCompleted
Initial characterization
Several preclinical studies describe effects on sleep, the stress response, and thermoregulation.
- Exploratory clinical research· 1980-1990Completed
Small clinical studies
Exploratory clinical studies (chronic insomnia, opioid withdrawal, pain) are published, with heterogeneous results.
- Critical review· 2000sCompleted
Critical reassessment of the literature
Several reviews highlight the difficulty of identifying a specific receptor and the heterogeneity of the available data.
- Modern research· OngoingOngoing
Occasional research studies
DSIP continues to be the subject of occasional research studies, with no large-scale program of randomized clinical trials to date.
Available analyses
No analytical document has been published for this molecule to date.
Open the analysis libraryFrequently asked questions
Is DSIP a sleeping pill?
No. Established: it does not induce rapid sleep onset like a conventional sleeping pill. Instead, studies describe effects on sleep architecture (deep sleep stages) in certain models.
Is there a DSIP receptor?
Requires further study: to date, no specific DSIP receptor has been clearly identified in the scientific literature. This is one of the major limitations in its characterization, despite nearly fifty years of research.
Is it approved as a medicine?
No. No major regulatory agency (FDA, EMA, etc.) has approved DSIP. It is presented here for educational and reference purposes (Research Use Only).
Why is a molecule that has been known for so long so rarely used?
Established: DSIP has been known since 1977. Requires further study: the lack of a clearly identified receptor and of large, modern clinical trials explains why it has remained confined to research.
What side effects have been reported?
Established: publications report generally good tolerability in small studies. Requires further study: the long-term tolerability profile in large populations has not been firmly established.
Can it be used for a sleep problem?
No — DSIP is not an approved medicine. The available data do not allow conclusions about its clinical efficacy. A sleep disorder requires care from a qualified healthcare professional.
Scientific publications
A selection of historical publications and recent reviews on DSIP. All are genuine and verifiable. An evolving bibliography.
Glossary
- Peptide
- A short chain of amino acids.
- Nonapeptide
- A peptide composed of 9 amino acids.
- Endogenous
- Produced naturally by the body.
- Deep sleep (delta)
- A stage of sleep characterized by slow waves on EEG, associated with recovery.
- Receptor
- A protein that receives a biological signal; no specific DSIP receptor has been clearly identified.
- Thalamus
- A deep brain structure involved in regulating wakefulness and sleep.
- HPA axis
- The hypothalamic–pituitary–adrenal axis, the main hormonal pathway of the stress response.
Continue your discovery
Read next
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Reference fact sheet — version 1.0, updated on 20 July 2026. The full regulatory and scientific framework is gathered in the “Important information” box at the top of the fact sheet.
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