DSIP (delta sleep-inducing peptide) is an endogenous nonapeptide, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, first characterised from rabbit brain by Schoenenberger and Monnier in 1977. Named for delta-EEG activity in early animal work, its receptor and physiological role remain unresolved in the literature. It is studied as a research-grade compound for laboratory use only.

What is DSIP researched for?

DSIP is studied across several research areas rather than one. The original and best-known is sleep and delta-EEG activity, first shown in rabbits (Schoenenberger and Monnier, 1977). Other documented themes include HPA-axis and stress-hormone modulation, antinociception in rodents, thermoregulation, antioxidant effects in rat tissue, and geroprotective signals in one mouse strain. Most of this work is old and animal-based, and the compound receptor and physiological role remain unresolved (Kovalzon and Strekalova, 2006). It is a research-use-only compound with no approved human indication.

What is the amino acid sequence and molecular weight of DSIP?

DSIP is a nonapeptide with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (one-letter code WAGGDASGE), reported in the 1977 characterisation by Schoenenberger and Monnier. Its molecular formula is C35H48N10O15 with a molecular weight of approximately 848.8 Da, and its CAS number is 62568-57-4 (PubChem CID 68816). It is a linear, unmodified peptide; the alpha-aspartyl form is the active one, while the beta-aspartyl isomer is markedly less active.

Does DSIP work as a sleep aid?

In research terms, no reliable human sleep benefit has been established. The delta-EEG effect DSIP is named for was seen in rabbits (Schoenenberger and Monnier, 1977), but the best controlled human study, a double-blind trial in chronic insomniacs, concluded DSIP is not likely to be of major therapeutic benefit (Bes and colleagues, 1992). Endogenous DSIP is also lower during sleep and tracks body temperature (Friedman and colleagues, 1994). A 2006 review calls the sleep link a still unresolved riddle (Kovalzon and Strekalova).

What are the reported side effects of DSIP?

No modern, controlled human safety or toxicology dataset for DSIP was located in the verified literature, so its human safety profile is undefined. One old, uncontrolled 1983 report noted no major side effects among 67 withdrawal patients (Dick, Grandjean and Tissot), but a small, uncontrolled study is not a safety demonstration and must not be read as one. DSIP should be treated as a research chemical of undefined human safety, handled strictly under research-use-only conditions.

Is DSIP approved for human use or available in Australia?

No. DSIP is not an approved therapeutic good and has no established human clinical indication. Substances not entered on the Australian Register of Therapeutic Goods are not approved for therapeutic use, and DSIP is handled strictly as a research-grade material for laboratory research only. It is not a RetaLABS product. For the Australian regulatory framework around research peptides, see the Research Peptides Legal Status in Australia guide.

DSIP Research Guide Australia 2026

Q: How quickly does DSIP act, and what is its half-life?

Because DSIP is a research-use-only compound, no human onset or subjective-effect timeline is described here. Pharmacokinetically, injected DSIP is degraded rapidly in blood by enzymatic cleavage, giving a short, minutes-scale plasma half-life (Graf, Saegesser and Schoenenberger, 1987). The frequently repeated figure of exactly 15 minutes is not tied to a verified primary source and should not be treated as established. DSIP reaches the brain through a saturable transport mechanism (Zlokovic and colleagues, 1989).

What Is DSIP?

Delta sleep-inducing peptide (DSIP) is an endogenous nonapeptide, a chain of nine amino acids with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (one-letter code WAGGDASGE). It was first isolated and sequenced from the cerebral venous blood of rabbits by G. A. Schoenenberger and M. Monnier at the University of Basel, and takes its name from the delta-wave (slow-wave) EEG activity observed in those early animal experiments.

Despite the descriptive name, DSIP is one of the least resolved neuropeptides in the literature. No receptor, gene or definitive physiological role has been isolated, and the best controlled human sleep study is negative. This guide summarises what the primary literature does and does not support, framed strictly as laboratory research on a research-use-only compound.

DSIP at a glanceSequence: Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (WAGGDASGE, 9 amino acids) · Molecular formula: C35H48N10O15 · MW: ~848.8 Da · CAS: 62568-57-4 · PubChem CID: 68816 · Class: endogenous neuropeptide · First characterised: Schoenenberger and Monnier, 1977 · Status: research-use-only, not an approved therapeutic

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Discovery and Background

DSIP research began with the humoral theory of sleep. Working at the University of Basel in Switzerland, Marcel Monnier and Guido Schoenenberger electrically stimulated the thalamus of rabbits to induce a sleep-like delta-EEG state, then collected cerebral venous blood and searched it for a transferable sleep-associated factor. The active principle was purified and identified as a nonapeptide, whose amino-acid analysis, sequence, chemical synthesis and delta-EEG activity were reported in 1977 and detailed further in the 1978 DSIP XI paper.

Some secondary sources date the discovery to 1974, referring to earlier work on the crude humoral factor. The peer-reviewed characterisation of the defined nonapeptide, the sequence researchers use today, is the 1977 report. Later reviews established DSIP as a linear, unmodified peptide that is unusually hydrophilic yet still crosses into the central nervous system, and catalogued a broad and inconsistent range of reported activities.

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Mechanism of Action: What Is Known and Unknown

Unlike most signalling peptides, DSIP has no identified molecular target. A 2006 review in the Journal of Neurochemistry attributes the weakness of the DSIP-as-sleep-factor hypothesis directly to the lack of an isolated DSIP gene, protein and receptor, and describes the peptide's natural occurrence and biological activity as still obscure. Any specific-receptor claim (for example GABA-B, NMDA or direct opioid-receptor action) should be treated as unproven.

1. A pleiotropic modulator, not a single-pathway agonist

Across the older literature DSIP behaves as a broad modulator with many weak, context-dependent effects rather than one strong action. Reviews by Graf and Kastin (1984) and Schoenenberger (1984) catalogue effects on sleep, stress hormones, thermoregulation, nociception and oxidative markers that do not resolve into a single mechanism.

2. Central nervous system access

Despite being hydrophilic, DSIP crosses the blood-brain and blood-CSF barriers. Banks and colleagues (1982) showed passage into CSF in dogs that correlated with protein binding, and Zlokovic and colleagues (1989) demonstrated a high-affinity saturable transport mechanism at the blood-brain barrier of the perfused guinea-pig brain, where unlabelled DSIP inhibited uptake of labelled DSIP.

3. Rapid degradation

Injected DSIP disappears quickly from blood through enzymatic degradation, with phosphorylated analogues degrading more slowly (Graf, Saegesser and Schoenenberger, 1987). A short, minutes-scale plasma half-life is reported consistently, though no single precise half-life value is well established.

4. A counterintuitive endogenous rhythm

In humans, plasma DSIP-like immunoreactivity follows a diurnal rhythm that tracks body temperature and is actually lower during REM and slow-wave sleep than during wakefulness (Friedman and colleagues, 1994). This observation complicates the simple picture of DSIP as a sleep-promoting hormone.

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Sleep and Delta-EEG Research

Sleep is the original and most-cited DSIP research theme, and also the one where human evidence is weakest.

Founding animal study: intraventricular infusion of the synthetic nonapeptide enhanced delta-EEG activity in the neocortex and archicortex of rabbits under double-blind conditions (Schoenenberger and Monnier, 1977). This is the result the compound is named for, and it is an animal finding.
Controlled human study, negative: in chronic insomniac patients, a double-blind study concluded that short-term treatment with DSIP is not likely to be of major therapeutic benefit, with any improvements weak and confounded by placebo (Bes and colleagues, 1992).
Human physiology, contradictory: endogenous plasma DSIP is lower during sleep and tracks temperature rather than sleep depth (Friedman and colleagues, 1994).

The 2006 Kovalzon and Strekalova review summarises the field by calling the DSIP-sleep link a still unresolved riddle. In research terms, delta-EEG effects are reproducible in some animal models, but a reliable human sleep benefit has not been established.

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Stress and HPA-Axis Research

A second research theme is DSIP's interaction with the hypothalamic-pituitary-adrenal (HPA) axis. The results are mixed and inconsistent in direction.

Animal, positive signal: DSIP reduced CRF-induced corticosterone release in rats, with no effect on ACTH-induced release, suggesting an action at the pituitary (Graf, Kastin, Coy and Fischman, 1985).
Human, partial: intravenous DSIP reduced plasma ACTH-like immunoreactivity for at least three hours in healthy men, but plasma cortisol was unchanged (Bjartell and colleagues, 1989).
Human, negative: DSIP did not affect CRH-stimulated or meal-induced ACTH and cortisol secretion in healthy men (Späth-Schwalbe and colleagues, 1995).

Taken together, there is some anti-CRF and anti-ACTH signal in animals and in one human study, but a reliable cortisol-lowering or anti-stress effect in humans is not supported by the verified literature.

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Other Researched Domains

Beyond sleep and the HPA axis, DSIP appears across several smaller and older research literatures. Each entry below is an accurate map of what was reported, not a suggestion of any human effect.

Domain	Reported finding	Evidence level
Analgesia / antinociception	Antinociceptive effect via the spinal noradrenergic system; DSIP evokes Met-enkephalin release from brain synaptosomes	Rodent and in-vitro; opioid and noradrenergic-linked
Thermoregulation	Modulates body-temperature responses to serotonergic agonists through a 5-HT1A mechanism	Rat; bidirectional, dose and context-dependent
Oxidative stress	Pre-treatment normalised antioxidant enzyme activity and reduced lipid-peroxidation markers under cold stress	Rat tissue only
Withdrawal (alcohol / opioid)	Open-label report of symptom improvement in withdrawal patients	Old, uncontrolled human report; not replicated
Geroprotection / oncostatic	A DSIP-containing preparation (Deltaran) increased lifespan and reduced spontaneous tumour incidence in one mouse strain	Animal; not pure DSIP; single inbred strain

None of these findings has been established in controlled human research. Several rest on a single old or uncontrolled study, and the geroprotective work used a DSIP-containing preparation rather than pure DSIP, so it does not generalise to the peptide alone or to humans.

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Half-Life, Onset and What the Literature Reports

Because DSIP is a research-use-only compound, this guide does not describe subjective human effects, onset of any felt effect, or an experiential timeline. What the primary literature reports is pharmacokinetic and physiological, not experiential.

Half-life. Injected DSIP is degraded rapidly in blood by enzymatic cleavage, giving a short, minutes-scale plasma half-life (Graf, Saegesser and Schoenenberger, 1987). A single precise value, for example the 15 minutes often repeated online, is not tied to a verified primary source and should not be treated as established.

Central access. The peptide reaches the central nervous system through a saturable transport mechanism at the blood-brain barrier (Zlokovic and colleagues, 1989), so brain exposure is not simply proportional to the amount administered.

On how it makes you feel. There is no validated human dataset describing subjective effects, and the one controlled human sleep trial was negative (Bes and colleagues, 1992). The endogenous human rhythm is also counterintuitive, with DSIP lower during sleep (Friedman and colleagues, 1994). Any confident account of a felt effect is not supported by the verified evidence.

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Administration Routes in Research Protocols

DSIP has been studied by several routes across the animal and human literature. No standardised human dosing exists, and nothing here is a dosing or usage recommendation.

Route	Research context
Intracerebroventricular (ICV)	Used in the founding rabbit delta-EEG work to deliver peptide directly to the CNS
Intravenous (IV)	Route in the human ACTH, cortisol and withdrawal studies
Subcutaneous / intraperitoneal	Common in rodent pharmacology and stress-model studies

The short plasma half-life documented for DSIP is a central variable in research design, and is one reason more metabolically stable phosphorylated analogues were investigated in the degradation literature (Graf, Saegesser and Schoenenberger, 1987).

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DSIP vs Related Sleep and Recovery Peptides

Researchers interested in sleep, circadian and recovery peptides often compare DSIP with better-characterised compounds. The table contrasts research profiles only and does not rank the compounds or imply that any is interchangeable with another.

Compound	Primary research profile	Evidence maturity
DSIP	Delta-EEG and sleep, HPA-axis, broad modulation	Old, mostly animal; receptor unknown; human data weak
Epitalon	Pineal, circadian and telomere-related research	Mostly animal and small clinical; Russian literature
Selank	Anxiolytic and nootropic	Preclinical plus Russian clinical registration
Growth hormone (sleep axis)	Slow-wave sleep and GH secretion physiology	Well-characterised human physiology

Because deep (slow-wave) sleep and growth-hormone secretion are physiologically linked, the growth-hormone sleep axis is a useful point of comparison for sleep-related peptide research. This does not imply that DSIP alters growth-hormone secretion. For the circadian and pineal angle, see the Epitalon Research Guide. For the anxiolytic and nootropic profile of a better-characterised CNS peptide, see the Selank Research Guide and the Semax Research Guide. For the relationship between deep sleep and growth-hormone secretion, see the HGH and Sleep research guide.

Reconstitution and Storage (Research Handling)

DSIP intended for laboratory research is typically supplied as a lyophilised (freeze-dried) powder and reconstituted before use. General peptide handling practice applies.

Reconstitute by adding bacteriostatic or sterile water slowly down the vial wall, then swirl gently until dissolved; do not shake
Store lyophilised powder frozen and protected from light
Keep reconstituted solution refrigerated and minimise freeze-thaw cycles
DSIP is documented to degrade rapidly in plasma, so careful handling and prompt use of reconstituted material are consistent with its known instability

For step-by-step method and storage detail that applies across research peptides, see the Peptide Reconstitution and Storage Guide.

Research-Use and Regulatory Status

DSIP is not an approved therapeutic good and has no established human clinical indication. It is studied and supplied strictly as a research-grade material for laboratory use only, and nothing in this guide is medical, dosing or usage advice.

In Australia, substances that are not entered on the Australian Register of Therapeutic Goods (ARTG) are not approved for therapeutic use, and DSIP falls outside any approved-medicine framework. It is handled on a research-use-only basis. For how this applies to research peptides generally, see the Research Peptides Legal Status in Australia guide.

Sourcing and Documentation

All RetaLABS products are for laboratory research use only.

For related research reading, see the Epitalon Research Guide, the Selank Research Guide, the HGH and Sleep research guide, and the broader Nootropic Peptides Guide. Reconstitution method is covered in the Peptide Reconstitution and Storage Guide.

DSIP (Delta Sleep-Inducing Peptide) Sleep and Stress Research Guide: Mechanism, Evidence and Status

What Is DSIP?

Discovery and Background

Mechanism of Action: What Is Known and Unknown

Sleep and Delta-EEG Research

Stress and HPA-Axis Research

Other Researched Domains

Half-Life, Onset and What the Literature Reports

Administration Routes in Research Protocols

DSIP vs Related Sleep and Recovery Peptides

Reconstitution and Storage (Research Handling)

Research-Use and Regulatory Status

Sourcing and Documentation

Source Research-Grade DSIP 10mg in Australia

More Research Guides