DSIP: The Peptide Named After an Effect Its Best Human Trial Could Not Find

DSIP (delta sleep-inducing peptide) has not produced a clinically meaningful improvement in human sleep in the two placebo-controlled insomnia trials run outside its discoverers' group, which enrolled 6 and 16 patients. The nine-amino-acid peptide, with a molecular weight of 848.8 Da (daltons, the unit of molecular mass), is named for the deep-sleep brain waves it produced in rabbits in 1977, and FDA documents call it emideltide. On 24 July 2026 an FDA advisory committee voted 6–7, with 1 abstention, against adding it to the list of substances US pharmacies may compound, the only rejection among the seven peptides it reviewed.

DSIP is still sold widely as a research chemical, and no lab certificate can say whether it does anything for sleep. The primary literature shows how a compound came to carry a mechanism in its name with so little human evidence behind it. DSIP is grouped with the other cognitive enhancement & neuroprotection peptides on the site's category page.

The short version

• DSIP is a nine-amino-acid peptide, called emideltide in FDA documents, that was named in 1977 for the deep-sleep brain waves it triggered when infused into rabbits' brains.

• Its human evidence is sparse: the human studies FDA reviewed in 2026 were all intravenous (given into a vein) and all published between 1981 and 1998, none of the placebo-controlled ones enrolled more than 16 patients, and the two run by independent teams found no meaningful benefit.

• No trial has tested the under-the-skin injections sold on the research market, which are community-reported at about 100–500 mcg a dose, and FDA has found no safety information for that route.

• A purity percentage cannot tell DSIP from another small peptide, so the check that matters is a mass reading near 848.8 Da on the batch's lab report; Peptigrity holds 242 shop-published lab reports for DSIP (verified September 2026).

• As of September 2026 DSIP is not FDA-approved and not on the list US pharmacies may compound from, an FDA advisory committee voted 6–7 against adding it in July 2026, and the World Anti-Doping Agency's rule on unapproved substances may cover it in sport.

Does DSIP improve sleep in humans?

DSIP has not been shown to improve human sleep in trials run outside the research group that first tested it in people. In a randomised, double-blind, placebo-controlled trial of 6 patients with chronic insomnia (Monti, 1987), no sleep measure differed significantly from placebo. In a double-blind, placebo-controlled trial of 16 patients (Bes, 1992), the small gains on DSIP were judged weak and partly due to a chance change in the placebo group.

The 1992 paper, Effects of delta sleep-inducing peptide on sleep of chronic insomniac patients. A double-blind study (Bes et al.), gave 25 nmol/kg (nanomoles per kilogram of body weight) of DSIP or a glucose placebo intravenously on three afternoons and recorded each night's sleep by polysomnography. Polysomnography is an overnight recording of brain waves, breathing and movement. Sleep efficiency, the share of time in bed spent asleep, rose slightly. Sleep latency, the time taken to fall asleep, fell slightly. One measure of tiredness fell within the DSIP group, but no further measure changed, including the patients' own ratings of their sleep, and the authors concluded that short-term treatment "is not likely to be of major therapeutic benefit."

The 1987 trial, Study of delta sleep-inducing peptide efficacy in improving sleep on short-term administration to chronic insomniacs (Monti et al.), was a crossover: each patient received both DSIP at 25 nmol/kg and placebo, on randomised nights in two four-night blocks, and it was double-blind, so neither patients nor researchers knew which night was which. Sleep latency shortened slightly and total sleep rose by about 20 minutes, but none of the changes was significant, and the authors judged the effects of little clinical significance.

The positive results come from Schneider-Helmert's group, whose early papers were co-written with DSIP's co-discoverer, Guido Schoenenberger. In a 1987 study of 14 patients given 30 nmol/kg for seven nights, with placebo nights before and after, the average time to fall asleep fell from 58.4 minutes at baseline to 27.6 minutes by the last injection, according to FDA's summary. FDA's reviewers weighed all of it for the committee in the FDA Briefing Document Pharmacy Compounding Advisory Committee (PCAC) Meeting July 23-24, 2026, concluding that the clinical studies for chronic insomnia "appear to be inconclusive and at best preliminary."

The table below sets out the main human studies in that briefing document, with the rabbit experiment that named the peptide; RCT stands for randomised controlled trial, and open-label means everyone knew who received the peptide.

Three patterns run through the table. The positive sleep studies share one group and small numbers; the two trials from other groups found little or nothing; and every human study in the table gave DSIP intravenously, by a route and at doses the research market does not use. Four decades on, the disagreement has not been resolved: the issue is not an empty literature awaiting its first study, but a literature that was written, disagreed with itself, and then stopped.

Where did the name "delta sleep-inducing peptide" come from?

DSIP's name comes from a 1977 rabbit experiment by the Swiss group of Guido Schoenenberger and Marcel Monnier. Infused into the fluid-filled spaces of the rabbits' brains, the peptide increased delta waves, the slow brain waves of deep sleep. Of 9 synthetic peptides tested double-blind in 58 rabbits, including controls, only DSIP enhanced the deep-sleep patterns recorded on the electroencephalogram (EEG), a trace of the brain's electrical activity.

The paper, published in PNAS (Proceedings of the National Academy of Sciences) as Characterization of a delta-electroencephalogram (-sleep)-inducing peptide (Schoenenberger & Monnier, 1977), describes an observation that was real. The compound was named for what it did to rabbit EEG traces, and every later claim inherited that name.

This is the mechanism by which a marketing asset gets built into a molecule's identity. A compound called "delta sleep-inducing peptide" arrives pre-loaded with a claim, and the claim is restated every time the name is written, including in articles that never assert it directly.

Nothing about the 1977 result was overstated by the people who produced it. A rabbit EEG finding was reported as a rabbit EEG finding. What followed is that the name outlived the evidence supporting it.

What is DSIP, and why do FDA documents call it emideltide?

DSIP is a nine-amino-acid peptide, Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu (WAGGDASGE), with CAS registry number 62568-57-4, the chemical's catalogue identifier, and a molecular weight of 848.8 Da. Emideltide is its international nonproprietary name (INN), the generic name assigned under the World Health Organization's naming system. FDA uses emideltide but keeps the old name in brackets: the agency's page July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee lists "Emideltide (also referred to as delta sleeping inducing peptide (DSIP))."

The PubChem record, Delta Sleep-Inducing Peptide | C35H48N10O15 | CID 68816, gives the formula and the mass and describes a nine-amino-acid peptide found in neurons, peripheral organs and plasma. The naming split has one practical consequence: FDA spells the long form "delta sleeping inducing peptide", so a search of its records for the correct spelling can miss them, while "DSIP" and "emideltide" both find them.

Nine amino acids is short, and every amino acid in the sequence is a common one. That combination creates DSIP's specific verification problem: its composition overlaps other small peptides, so a mass measurement, not a purity figure, shows which peptide is in a vial, and the certificates collected on the DSIP lab tests page show how often sellers' vials match their labels.

Does DSIP have a receptor, and has anyone studied it since the 1980s?

DSIP has no identified receptor, the molecule a signal acts on: a 2019 handbook chapter noted that, 40 years after its isolation, neither a receptor nor a precursor peptide, the larger protein it would be cut from, had been found, and the mechanism by which it promotes sleep remained unknown. Human research on it has also stopped. The newest human study in FDA's 2026 review, a seven-patient open study of opioid detoxification, was published in 1998, and FDA's reviewers found nothing newer.

The observation appears in Sleep, Immunity, and Stress: Novel Insights From Drosophila (Williams, 2019), a chapter in the Handbook of Behavioral Neuroscience that traces the history of sleep research. Without a known precursor, it is not even clear how the body makes DSIP.

Take those two absences together and the shape of the problem is clear. A missing receptor is not by itself disqualifying, since plenty of peptides were studied for years before their targets were found. What makes it load-bearing here is the second absence: there has been no sustained modern effort that might have located one.

The compound is therefore not so much unproven as unexamined-since. Its file was opened, worked on intensively through the 1980s, and all but abandoned after 1998.

Why did the FDA advisory committee reject DSIP when it backed six other peptides?

The FDA advisory committee rejected DSIP, listed as emideltide, by 7 votes to 6 with 1 abstention on 24 July 2026, after FDA's reviewers found the evidence for every proposed use insufficient; it recommended the other six peptides it reviewed. One member who voted no cited "low-quality evidence around efficacy, the poor characterization of the bulk drug substance and the fact that there are approved medical therapies for all proposed uses."

The tally and that quotation, from Todd Durham of the Foundation Fighting Blindness, are reported in Peptide adcomm Day 2: Emideltide voted down in panel's 1st pushback; FDA had posted no minutes or vote record for the meeting as of September 2026. The uses under review were opioid withdrawal, chronic insomnia and narcolepsy, for a subcutaneous injection, one given under the skin, at 1 mg/mL. The original nominators had withdrawn their nomination, and FDA brought the substance to the committee regardless.

That withdrawal is also why DSIP left Category 2, FDA's list of bulk substances that may present significant safety risks, in April 2026. FDA's page Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks, current as of 22 April 2026, now lists "Emideltide (DSIP)" among substances "previously in category 2" whose nominations "were withdrawn by the nominators." The same entry states that FDA "has not identified safety-related information regarding emideltide for the proposed route of administration." Leaving Category 2 did not make DSIP compoundable: it is not on the 503A bulks list, the list of bulk ingredients US pharmacies may compound from, and the committee has now advised against adding it.

The same day, the committee recommended epithalon, spelled epitalon in FDA documents, which was also nominated for insomnia; its own evidence is examined in Epithalon, where the telomere findings come from cultured cells rather than people. The vote on DSIP is advisory. As of September 2026 FDA had published no proposed rule adding any of the six recommended peptides to the 503A bulks list, so nothing had changed in law for them either, and FDA Peptide Regulation 2025-2026 lays out the dated sequence. Outside a pharmacy, DSIP is sold as a research-use-only chemical, part of the grey market for peptides in which nobody upstream is answerable for a batch.

In sport, DSIP is not named in the World Anti-Doping Code International Standard Prohibited List 2026, which the World Anti-Doping Agency (WADA) publishes each year, but section S0 of that list prohibits at all times "any pharmacological substance which is not addressed by any of the subsequent sections of the List and with no current approval by any governmental regulatory health authority for human therapeutic use." FDA's reviewers found no country where emideltide is a registered drug in the database they searched, so an athlete subject to testing has no basis for assuming it is permitted; the anti-doping organisation that tests them can confirm its status.

What dose of DSIP has actually been tested in humans?

DSIP has been tested in humans only intravenously, at 25–35 nmol/kg, and has no established human dose. The two independent placebo-controlled insomnia trials used 25 nmol/kg (Monti 1987, n = 6; Bes 1992, n = 16), and the 35 nmol/kg figure comes from a seven-patient opioid-detoxification study (1998). That works out at about 1.5 mg a dose for a 70 kg adult at 25 nmol/kg, our arithmetic from PubChem's molecular weight. No trial has tested a subcutaneous dose.

The research market sells DSIP as vials for subcutaneous injection, and community-reported amounts run from about 100 to 500 mcg a dose, taken at night; no trial has tested any of them. Those amounts are roughly a third to a fifteenth of the 25 nmol/kg trial dose for a 70 kg adult, given by a different route. The community regimen is therefore not a scaled-down version of something that worked: the independent trials of the intravenous dose did not produce a meaningful result either.

The DSIP Reconstitution Calculator converts a vial's milligrams and the water added into syringe units. It does arithmetic on a figure the reader already has, and no published source says which figure to put into it.

Stop and seek care: swelling of the face or throat, difficulty breathing or hives after an injection are signs of a serious allergic reaction; spreading redness, warmth or pus at an injection site with fever is an infection; severe or persistent abdominal pain with vomiting on a GLP-1 drug can be pancreatitis; confusion, sweating or shaking on an IGF-1 or insulin-adjacent compound can be hypoglycaemia. Call your local emergency number (911 in the US, 112 in the EU, 999 in the UK, 000 in Australia) or go to an emergency department, and bring the vial and its label. Research-use vials are not approved products in any jurisdiction, even where a prescription product of the same molecule exists; no article on this site replaces a clinician who knows your history.

Why do community reports on DSIP disagree?

Community reports on DSIP disagree in the way a weak effect on a placebo-sensitive outcome predicts: accounts range from markedly deeper sleep within the first nights to no change at all (community-reported). Sleep responds strongly to placebo. In the meta-analysis Effect of Placebo Conditions on Polysomnographic Parameters in Primary Insomnia: A Meta-Analysis (Winkler & Rief, 2015), covering 32 studies and 3,969 participants, placebo groups achieved 63.56% of the drug response, on polysomnography as well as in self-report.

Neither group is lying. Both are reporting an experience accurately, and the evidence simply does not support treating either experience as generalisable to a third person.

The 1992 trial shows the gap from the other side: sleep efficiency and latency moved slightly on DSIP while the patients' own ratings of their sleep did not change. Self-report cannot measure the one thing DSIP is named for, which is why any trial able to settle the question has to record sleep architecture, the pattern of sleep stages through the night, directly. Readers who want to add their own account can post it on the grey market peptide forum, where it is read as anecdote rather than data.

Which DSIP claims survive the evidence?

None of the seven common DSIP claims is established in humans. The delta-sleep claim rests on a 1977 rabbit experiment and did not appear in the 16-patient placebo-controlled trial; faster sleep onset is inconsistent across trials; lower cortisol did not appear in a 1995 placebo-controlled study; withdrawal relief rests on open, uncontrolled studies; the antioxidant claims are animal and cell data; the mechanism is unknown; and FDA has found no safety information for the route people use.

The cortisol result comes from Delta-sleep-inducing peptide does not affect CRH and meal-induced ACTH and cortisol secretion (Späth-Schwalbe et al., 1995), in which intravenous DSIP at total doses of 3–4 mg left the hormone responses of 20 healthy men "almost identical" to placebo. ACTH is the pituitary hormone that drives cortisol release.

How does DSIP compare with other sleep peptides?

Of the three research peptides sold for sleep, DSIP is the only one tested in placebo-controlled human sleep trials, and the only one an FDA advisory committee has voted against. Epithalon, nominated for insomnia, was recommended by the same committee on 24 July 2026, and its human data are non-blinded cohorts from its developers' group. Pinealon rests on rodent studies and developer-group reports, and melatonin, the over-the-counter comparator, has a modest effect on sleep onset.

Median prices are per milligram across all vial sizes, read from each compound's price page on 25 September 2026 (verified September 2026). They exclude shipping, taxes and customs, the lowest offers are often large vials, and the DSIP price comparison lists every DSIP offer with its vial size. Readers weighing the three research compounds against each other will find them in Peptides for Sleep, which sets out the evidence behind each.

How do you verify a DSIP vial before you buy it?

A DSIP vial is verified above all by a mass measurement, matched to the batch, showing a mass near 848.8 Da, because DSIP's short sequence is its specific sourcing risk. Nine amino acids, all common, mean that a purity figure says almost nothing about identity: a vial can be 99% pure and contain a different small peptide entirely. The CAS number, the net peptide content and a test for bacterial contamination cover what mass cannot.

The purity figure comes from HPLC (high-performance liquid chromatography), which measures what share of the peptide material in a sample is one compound. The mass comes from mass spectrometry, which weighs the molecules and so shows whether the main compound has the right mass. Net peptide content is how many milligrams of peptide a vial actually holds, as against salts and water. A certificate of analysis (COA) is the lab report for one batch. Endotoxin is bacterial debris that causes fever when injected. It is measured by the LAL test, which uses an extract of horseshoe-crab blood cells that clots in its presence.

Identity is the subject of Mass Spectrometry for Peptides, which shows what a spectrum must read before it counts as confirmation. Purity and quantity are separate axes, which is why Peptide Net Content explains how a 10 mg vial can hold less than 10 mg of peptide. Reading a certificate line by line is covered in How to Read Peptide Lab Test Results, from the chromatogram to the mass spectrum.

The site's guide how to test your peptides explains how to get a vial tested independently. The peptide shops directory lists each shop's published certificates and reviews.

What do Peptigrity's lab records show for DSIP?

Peptigrity holds 242 certificates of analysis for DSIP from 21 laboratories and 156 shops (verified September 2026), all for single vials, with a recency-weighted purity index of 99.23, a mean that counts recent tests more, and a median measured content of 105% of the label claim. The records show what was in the vials shops chose to have tested. They say nothing about whether DSIP works or is safe.

HPLC purity is tightly grouped: the median is 99.34%, 85% of results reach 99% or higher, and 10 fall below 98%. Measured content is not: of the 238 vials with a measured content, 17 held less than 90% of the labelled amount and 43 held more than 120%, so the amount in a dose drawn from a labelled vial can be well off in either direction. Endotoxin was reported on 52 of the 242 certificates (21%), and 56 (23%) have been confirmed on the issuing lab's own portal. The most-tested vial sizes are 5 mg (135 certificates) and 10 mg (85).

How each compound's index is weighted, with tests from the last 90 days counting fully and older ones less, is explained on the site-wide Purity Index, where DSIP sits alongside 63 other compounds.

One caveat applies across the whole dataset: published certificates are the ones vendors chose to publish, which makes the sample selection-biased rather than a random market survey. The caveat has extra force for a nine-amino-acid peptide, because a certificate reporting only HPLC purity does not establish that the vial contains DSIP at all.

What trial would settle whether DSIP works?

A trial that would settle whether DSIP works would measure slow-wave sleep by polysomnography in a randomised, double-blind, placebo-controlled study of a defined insomnia group, dosing under the skin, the route people use, with blood sampling for drug levels. Every trial in FDA's 2026 review gave DSIP intravenously, at doses roughly 3 to 20 times the community-reported amounts, and no placebo-controlled trial enrolled more than 16 patients.

No trial of that design has been published, and FDA's 2026 review found no human study newer than 1998. No sponsor has an obvious commercial reason to run one after the committee's vote against a pharmacy route, which after nearly fifty years is itself informative.

Where does this leave DSIP?

DSIP is left as a compound whose reputation rests almost entirely on its name. The underlying biology may still be real, since a nine-amino-acid peptide tied to sleep in animals is a reasonable object of study, but nearly fifty years on the human evidence remains thin, inconsistent and old, and the most recent expert review of it, the July 2026 committee vote, went against it.

The two small placebo-controlled trials from 1987 and 1992 are still the best tests anyone has run on it. DSIP is not currently a sleep intervention with an evidence base. The honest framing is an unresolved question rather than a working tool, for anyone researching the compound itself. The gap between those two positions is exactly the width of the word "inducing" in its name.

A reader who already holds a vial can check its lot number against the certificates on file before anything else.

Frequently Asked Questions

Does DSIP work for sleep?

DSIP has not been shown to work for sleep in trials run outside the group that first tested it in people. The two independent placebo-controlled insomnia trials, with 6 and 16 patients, found, respectively, no significant difference from placebo and only weak changes of no major therapeutic benefit. The positive results come from small studies by one research group and were not reproduced by the independent trials.

Why is it called delta sleep-inducing peptide if it may not induce sleep?

DSIP's name comes from a 1977 experiment in which the peptide, infused into rabbits' brains, increased delta-wave EEG activity. It describes an animal EEG observation, not a demonstrated human clinical effect.

What happened at the FDA meeting in July 2026?

On 24 July 2026 FDA's Pharmacy Compounding Advisory Committee voted 6–7, with 1 abstention, against adding DSIP, listed as emideltide, to the 503A bulks list for opioid withdrawal, chronic insomnia and narcolepsy. It was the only one of seven peptides the committee declined to recommend, after FDA's reviewers found the evidence for each use insufficient. The vote is advisory; FDA makes the final decision.

Can a US pharmacy compound DSIP now?

No. As of September 2026 DSIP is not on the 503A bulks list, the list of bulk ingredients US pharmacies may compound from, and the advisory committee voted against adding it in July 2026. Its April 2026 removal from FDA's Category 2 list followed the withdrawal of its nomination and did not make it compoundable.

Is DSIP banned in sport?

DSIP is not named on WADA's 2026 Prohibited List, but that does not mean it is permitted. Section S0 prohibits at all times any substance without a current approval for human therapeutic use from a government health regulator, and FDA's reviewers found no country where emideltide is a registered drug in the database they searched. Athletes subject to testing can confirm its status with their anti-doping organisation.

How do I know my vial is really DSIP?

A batch-matched mass-spectrometry result showing a mass near 848.8 Da is the essential check that a vial contains DSIP. HPLC purity alone cannot establish identity for a nine-amino-acid peptide made of common amino acids.

Is DSIP safe?

DSIP's safety is unknown beyond small, short studies. Those studies reported good tolerability, apart from headaches in a few patients in the 1984 withdrawal study, but FDA has no safety information for the subcutaneous route the market uses, and long-term human safety has never been studied. Talk to a clinician before using DSIP if you have insomnia that has lasted for months or are going through opioid or alcohol withdrawal: both have approved treatments, and withdrawal can need medical supervision.

This article is for educational and informational purposes only and does not constitute medical advice. Peptides discussed may be investigational compounds not approved by the FDA (or equivalent regulators in your jurisdiction) for human use. Peptigrity does not recommend doses; any dose figure above is an approved-label value, a published-trial value or a community report, and is labelled as such. Always consult a qualified healthcare provider before using any peptide or research compound. Peptigrity is an independent review platform and does not sell, endorse, or recommend specific products or vendors.