DSIP (Delta Sleep-Inducing Peptide)
DSIP Regulatory Status
DSIP holds no marketing authorisation from the MHRA, EMA or FDA and has not been through regulatory review in any jurisdiction. It carries an International Nonproprietary Name, emideltide, which reflects a WHO naming decision rather than any assessment of safety or efficacy.
Key facts
- MHRA status
- Not authorised
- EMA status
- Not authorised
- FDA status
- Not approved
- INN
- Emideltide — a naming decision only
- UK supply basis
- Laboratory research only
- Claimed indication
- None may be claimed
What an INN is and is not
An International Nonproprietary Name is assigned by the WHO so a substance has one unambiguous generic name worldwide. Assignment happens on request and reflects a need to identify the compound consistently. It says nothing whatsoever about safety, efficacy or approval, and a compound can hold an INN indefinitely without ever being authorised anywhere. DSIP's INN is emideltide.
Why this compound needs the point made clearly
DSIP is unusual among research peptides in carrying a name that asserts a therapeutic effect. A compound called delta sleep-inducing peptide, holding an INN, reads as though it were a medicine at some stage of development. It is not. The name records a 1977 hypothesis, the INN records a naming request, and neither records an assessment by anyone.
Research material referenced
DSIP 5mg — third-party HPLC tested
The claim we do not make
We do not say DSIP induces sleep, improves sleep, or affects sleep in any person. The published basis for such a claim is an EEG observation in rabbits from 1977, with no receptor, no gene and no confirmed mechanism behind it. Making the claim would be inaccurate on the science before it was a problem under the UK framework — where a therapeutic claim about material supplied for research converts it into an unlicensed medicine.
The enforcement context
The MHRA opened investigations into UK retailers making therapeutic claims about unregulated peptide products in April 2026. Sleep claims about a compound literally named for sleep are close to the top of the list of things that framework is concerned with, which is why this category is written the way it is.
What would change the position
A marketing authorisation following an application and assessment. For DSIP specifically that would first require the mechanistic groundwork the field never completed — a receptor, a mechanism, and controlled trials in humans. None of that exists.
Extended research context
The DSIP (Delta Sleep-Inducing Peptide) deep dive
Deep dive: a name that was a hypothesis, not a finding
In 1977 the Schoenenberger-Monnier group in Basel electrically stimulated the thalamus of a sleeping rabbit, collected blood draining from its brain, isolated a peptide fraction, and reported that administering it into the ventricles of awake rabbits produced delta-wave EEG activity. They named it delta sleep-inducing peptide. By the standards of the time this was careful, imaginative work, and they followed it properly - the 1978 Pflugers Archiv paper reported sequence, synthesis and activity of the synthetic nonapeptide rather than stopping at a suggestive fraction. The problem is not the original research. It is that a name recording a hypothesis has been read ever since as a summary of established pharmacology, and almost nobody checks whether it was earned.
Deep dive: the three things that are missing
A proposed endogenous peptide becomes accepted biology by a recognisable route. The gene is located. The precursor protein is characterised. A receptor is identified, giving a mechanism and a testable target. DSIP has completed none of these in nearly fifty years. The receptor gap is the most disabling - without one there is no mechanism to test, no dose-response to build, no antagonist to design, and no way to establish that an observed effect runs through the proposed pathway at all. The gene gap is the hardest to explain away: modern genomics located MOTS-c inside a short open reading frame nested within the mitochondrial 12S rRNA gene, sequence already annotated as something else. That a peptide described in 1977 still has no identified gene in any genome is a substantive observation, not an accident of effort.
Deep dive: why 519 papers is not 519 confirmations
DSIP has roughly 519 indexed PubMed records - more than Selank's 135 or Semax's 231. Publication volume tracks how interesting a question is, not how well it has been answered. A tractable question generates a burst of work and then stops; a question that resists resolution generates papers indefinitely, each a further attempt rather than a further confirmation. Kovalzon's 2006 review in the Journal of Neurochemistry states the field's own assessment in its title: a still unresolved riddle. Reading any individual DSIP paper without that context invites mistaking activity for consensus.
Research applications
- ▸Historical study of humoral sleep-factor hypotheses
- ▸Electroencephalography and delta-wave research methodology
- ▸Structure-activity work on flexible, acidic short peptides
- ▸Comparative work on peptides lacking identified receptors
- ▸Analytical method development for tryptophan-containing peptides
Handling checklist
- ✓Store lyophilised material cold, dry and protected from light
- ✓No reducing agent needed — the sequence contains no cysteine
- ✓No methionine oxidation to expect; a +16 Da satellite warrants explanation
- ✓Protect from prolonged light — the single tryptophan is mildly photosensitive
- ✓Expect pH-dependent solubility; the peptide is strongly acidic with no basic residue
- ✓Aliquot to avoid repeated freeze-thaw cycles
Common research-handling mistakes
Learnt from thousands of researcher orders across our UK labs.
✗ Treating the name as evidence of the effect
Fix: The name records a 1977 hypothesis from a single rabbit EEG study. It is not a summary of established pharmacology.
✗ Citing the 1977 paper as proof DSIP induces sleep
Fix: It reports delta-wave EEG activity in rabbits after intraventricular administration — a narrower claim than inducing sleep, in one species, by a route that bypasses every normal barrier.
✗ Assuming DSIP is an established endogenous human peptide
Fix: No gene has been identified in any species, no precursor characterised and no receptor found.
✗ Reading 519 papers as 519 confirmations
Fix: Volume reflects an unresolved question attracting sustained attempts, not accumulated confirmation.
✗ Making any sleep claim about supplied material
Fix: The evidence does not support it and a therapeutic claim about research material is what MHRA enforcement targets.
Continue researching
Peer-reviewed guides, comparators and matched reference materials.
Related questions researchers ask
- What is DSIP?
- Does DSIP actually induce sleep?
- How was DSIP discovered?
- Does DSIP have a receptor?
- What are delta waves?
- Is DSIP approved anywhere?
Frequently asked questions
- Is DSIP legal in the UK?
- It is supplied as a material for laboratory research. It is not a licensed medicine and cannot be prescribed or dispensed.
- Does having an INN mean DSIP is a drug?
- No. An INN is a naming decision by the WHO. It carries no assessment of safety or efficacy and no approval.
- Why will you not describe DSIP's effects on sleep?
- Because the evidence is a 1977 rabbit EEG observation with no established mechanism, and because a therapeutic claim about research material is what MHRA enforcement targets.
Primary sources & clinical trials
Peer-reviewed research and registered trials from PubMed, ClinicalTrials.gov, PubChem, FDA and NIH. All links open in a new tab and point to the primary source, so every claim can be verified at origin.
- RefMHRA — Medicines and Healthcare products Regulatory Agencygov.uk
- EMAEuropean Medicines Agencyema.europa.eu
- FDAFDA Drug Approval Searchaccessdata.fda.gov
- PubMedKovalzon VM, DSIP: a still unresolved riddle — J Neurochem 2006 (PMID 16539679)pubmed.ncbi.nlm.nih.gov
- PubMedSchoenenberger GA et al., Characterization of a delta-EEG (sleep)-inducing peptide — PNAS 1977 (PMID 265572)pubmed.ncbi.nlm.nih.gov
- PubMedSchoenenberger GA et al., DSIP XI: amino-acid analysis, sequence, synthesis and activity — Pflugers Arch 1978 (PMID 568769)pubmed.ncbi.nlm.nih.gov
- PubChemPubChem · Delta sleep-inducing peptide (CID 68816)pubchem.ncbi.nlm.nih.gov
- PubMedPubMed — DSIP literaturepubmed.ncbi.nlm.nih.gov
- GuidelineGoogle — Creating helpful, reliable, people-first contentdevelopers.google.com
Written and reviewed by
Jack Muncaster · Founder, UK Peptides
Jack founded UK Peptides in Manchester after repeatedly receiving research compounds with missing or recycled paperwork. He is responsible for supplier selection, batch release decisions and the content published in this research library. Every article here is sourced to primary literature and every product page to a signed third-party certificate.
More DSIP (Delta Sleep-Inducing Peptide) articles
- What Is DSIP? A Research OverviewDSIP is a nonapeptide isolated from rabbit blood in 1977 and named for an observed EEG effect. No gene, precursor or receptor has ever been identified.
- Does DSIP Actually Induce Sleep? What the Evidence ShowsDSIP is named for a sleep effect. The evidence has never firmed up: no gene, no receptor, and a literature its own reviewers call an unresolved riddle.
- How DSIP Was DiscoveredSchoenenberger and Monnier stimulated a sleeping rabbit's thalamus, collected the blood draining from its brain, and isolated a peptide from it. The 1977 method.
- The Missing Biology: No Gene, No Precursor, No ReceptorFor an endogenous signalling peptide, DSIP is missing all three of the things that normally establish one. Why that absence matters more than any single study.
- What Delta Waves Are, and Why DSIP Is Named for ThemDelta waves are high-amplitude, low-frequency EEG activity below about 4 Hz, characteristic of deep non-REM sleep. What they measure and what they do not.
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