What does DSIP stand for?

Delta sleep-inducing peptide. The name comes from the circumstances of its discovery in the 1970s, when it was isolated from the blood of rabbits in which sleep had been induced and early work associated it with delta-wave sleep activity. It is worth treating the name as a historical label rather than a description of established function, because the research that followed did not confirm it as cleanly as the name suggests.

What is DSIP chemically?

A nonapeptide, nine residues, with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu. It is an unremarkable molecule structurally: all natural L-amino acids, no modified residues, no unusual end groups, and three glycines giving the backbone a good deal of flexibility. Nothing about the structure is exotic, which makes it straightforward to synthesise and to characterise analytically.

Does DSIP actually induce sleep?

The honest answer is that the literature has not settled this. The original rabbit experiments reported an association with delta-wave sleep, which is where the name came from, but attempts to reproduce and characterise a consistent effect have given mixed results across different models and protocols. A compound named for one function that has been studied for several unrelated ones, without a clear mechanism established for any of them, is a compound whose function is still genuinely open.

What else has DSIP been studied for?

The published literature covers a notably scattered range of contexts beyond sleep. That breadth is sometimes presented as versatility; it is more honestly read as a sign that no single well-characterised mechanism has been pinned down. A molecule with one clear function tends to accumulate a focused literature, not a diffuse one.

Is DSIP an approved medicine?

No. It holds no marketing authorisation in the UK and is not a licensed medicine here, despite having been known for around fifty years. That longevity without approval is itself informative: compounds that work reliably and safely for a defined indication generally do not remain in research limbo for five decades. Material sold under this name is supplied for in-vitro laboratory research only.

No. We do not stock DSIP and there is no Certificate of Analysis for it in our library. It is covered here because it draws steady search interest and most available information repeats the promise embedded in its name without noting how unsettled the evidence is.

What is DSIP?

5 min read · Updated October 2026 · MY PEPTIDES Research Team

Key facts

DSIP stands for delta sleep-inducing peptide, a nonapeptide with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu. It was first isolated in the 1970s from the blood of rabbits in which sleep had been induced, and it was named for the delta-wave sleep activity that early work associated with it. That name has proved considerably more confident than the subsequent literature. Attempts to reproduce and characterise a consistent sleep-related effect have produced mixed results across models, and the peptide has also been studied in a range of unrelated contexts, which is not the pattern of a molecule with one well-defined function. It holds no marketing authorisation in the UK and is not an approved medicine. MY PEPTIDES does not stock it. General information for laboratory context only, not medical advice.

The short answer

DSIP is a nine-residue peptide, sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu, isolated in the 1970s from the blood of rabbits in which sleep had been induced. The name, delta sleep-inducing peptide, records what the earliest work thought it had found.

Fifty years later that name remains the most confident claim anyone has made about the molecule. The literature since has been mixed, and the compound has been studied across a scattered range of contexts without a clear mechanism being established for any of them.

A name doing more work than the evidence

There is a specific hazard in compounds named for an early observation, and DSIP is close to the textbook case.

The name asserts a function. It was coined from experiments associating the peptide with delta-wave sleep activity in rabbits, at a time when the methods for isolating and characterising such molecules were far less refined than they are now. Every subsequent search for information about the compound starts from that assertion, and product copy understandably leans on it, because a peptide called "delta sleep-inducing peptide" markets itself.

What followed is less tidy. Efforts to reproduce and characterise a consistent sleep-related effect have produced mixed results depending on the model and the protocol, and the peptide has also been examined in a number of unrelated contexts. That scattered pattern is the opposite of what a well-understood molecule looks like. When a compound has a defined mechanism, research concentrates around it; when it does not, the literature disperses.

Fifty years is also a long time for a compound to remain unresolved. That is not proof it does nothing, but it is a reasonable prior.

Structurally, it is ordinary

Nothing about the chemistry explains the attention. Nine residues, all natural L-amino acids, no modified or D-form residues, no unusual end groups, and three glycines which make the backbone notably flexible. There is no secondary structure to speak of at this length.

Practically this makes it easy to synthesise and unambiguous to characterise: a nonapeptide gives a clean chromatographic peak and an exact mass, so a competent certificate of analysis should leave no doubt what is in the vial. The usual handling constraints apply, and our guide on storing research peptides covers them.

The flexibility is worth one note for anyone designing work with it. A highly flexible short peptide has no single preferred conformation, which is one plausible reason why establishing a specific receptor interaction has proved difficult.

What the research does not establish

No regulator has authorised DSIP for any human use, and it is not a licensed medicine in the UK. Supplying an unlicensed product for human medicinal use is unlawful under the Human Medicines Regulations 2012 however a listing describes it, and our guide on whether peptides are legal in the UK sets out the framework.

For anyone reading the marketing: claims about sleep in humans rest on the name and on early animal work, not on a settled evidence base. That gap between a confident label and an unsettled literature is the single most useful thing to know about this compound.

Where MY PEPTIDES stands

We do not stock DSIP. There is no Certificate of Analysis for it in our library and no product page for it on this site, and this guide is not an offer to supply it. What we do supply, and the documentation standard we hold it to, is set out in our guide on certificates of analysis.

The bottom line

DSIP is a structurally ordinary nonapeptide carrying an unusually confident name. The sleep association comes from 1970s rabbit experiments and has not been cleanly confirmed since, and the scattered literature suggests no single mechanism has been established. It is easy to make and characterise, it is not an approved medicine, and we do not supply it.

All compounds referenced on this site are discussed strictly in the context of in-vitro laboratory research. Nothing here is a medicine, a supplement or a therapeutic product, nothing here describes administration to humans or animals, and this guide is general information rather than medical, legal or research advice.

Frequently asked questions

What does DSIP stand for?: Delta sleep-inducing peptide. The name comes from the circumstances of its discovery in the 1970s, when it was isolated from the blood of rabbits in which sleep had been induced and early work associated it with delta-wave sleep activity. It is worth treating the name as a historical label rather than a description of established function, because the research that followed did not confirm it as cleanly as the name suggests.
What is DSIP chemically?: A nonapeptide, nine residues, with the sequence Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu. It is an unremarkable molecule structurally: all natural L-amino acids, no modified residues, no unusual end groups, and three glycines giving the backbone a good deal of flexibility. Nothing about the structure is exotic, which makes it straightforward to synthesise and to characterise analytically.
Does DSIP actually induce sleep?: The honest answer is that the literature has not settled this. The original rabbit experiments reported an association with delta-wave sleep, which is where the name came from, but attempts to reproduce and characterise a consistent effect have given mixed results across different models and protocols. A compound named for one function that has been studied for several unrelated ones, without a clear mechanism established for any of them, is a compound whose function is still genuinely open.
What else has DSIP been studied for?: The published literature covers a notably scattered range of contexts beyond sleep. That breadth is sometimes presented as versatility; it is more honestly read as a sign that no single well-characterised mechanism has been pinned down. A molecule with one clear function tends to accumulate a focused literature, not a diffuse one.
Is DSIP an approved medicine?: No. It holds no marketing authorisation in the UK and is not a licensed medicine here, despite having been known for around fifty years. That longevity without approval is itself informative: compounds that work reliably and safely for a defined indication generally do not remain in research limbo for five decades. Material sold under this name is supplied for in-vitro laboratory research only.
Do you sell DSIP?: No. We do not stock DSIP and there is no Certificate of Analysis for it in our library. It is covered here because it draws steady search interest and most available information repeats the promise embedded in its name without noting how unsettled the evidence is.