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Lexicon
Sleep

Sleep Blend SZ352

A ready-made sleep stack to promote falling and staying asleep, several components in one product.

1 min read 9 sources

To the product To the sources
Vial with clear liquid, blue cap and the black TPD label of Sleep Blend SZ352 on a white podium with a blue light ring, lab glassware and glass spheres behind it
No study of its own · not approved

Summary

At a glance

Sources checked on 26 Oct 2026

On the stack itself
0 studies

neither in the trial registry nor in PubMed, as of 26 Oct 20267

DSIP duration up to
20 hours

after one dose into a vein, sleepiness after about one hour2

7 nights, double-blind
14 people

DSIP in chronic insomnia: sleep and daytime function better3

Double-blind placebo trial
16 people

chronic insomnia: weak effects, no major benefit expected4

  • Sleep Blend SZ352 is a ready-made sleep stack meant to help with falling and staying asleep. The lexicon does not name its components.
  • There is no study on the stack itself, neither in the trial registry nor in PubMed. DSIP, the example from the entry, has no registered trial either.78
  • DSIP is a nonapeptide that mainly promoted deep sleep in rabbits, rats and mice. No receptor for it is known to this day.16
  • In humans there are only small studies from the 1980s and 1990s: 14 people slept better in one double-blind study, 16 people in another barely did.34
  • Neither the stack nor DSIP is approved. Sleep hygiene remains the base, everything here is the state of research, not a recommendation.9
Profile

Updated May 2026

Class
Sleep blend
Use
Evening

ready to use

Goal
Falling and staying asleep
Status
Component-based

blend not study-proven

Sizes
10 ml

1 size in the shop

Contents 13 sections
  1. At a glance
  2. What is Sleep Blend SZ352?
  3. How it works
  4. Use
  5. Dosing
  6. What the research shows
  7. Research status
  8. Side effects
  9. Storage
  10. Related compounds
  11. FAQ
  12. Glossary
  13. Sources

What is Sleep Blend SZ352?

Sleep Blend SZ352 is a ready-made sleep stack that combines several components to promote falling and staying asleep. Like Relaxation PM, it is a combination product aimed at better sleep.

Comparison

Stack or single peptide

Sleep products in the TPD lexicon, as described there. Tap a card to open its entry.

Ready-made evening stack Relaxation PM
Ready-made sleep stack Sleep Blend SZ352
Single peptide with older studies DSIP

The two stacks do not name their composition in the lexicon. Neither has a study of its own. 7

How it works

Sleep stacks calm the nervous system and are meant to ease the transition into sleep and support staying asleep. The exact effect depends on the composition.

Where it acts

Where DSIP acted in studies

Grey = seen in studies on DSIP, not on the stack.

  1. Brain

    DSIP: sleepiness after about one hour, mainly more deep sleep in animal studies2

    Observed in trials
Network of glassy, glowing blue nerve cells with fine points of light
Sleep stacks are meant to calm the nervous system and support staying asleep. Symbolic image.

Use

Dosing. Loading the dosing information …
Sleep Blend SZ352 vial with the black TPD label and a disposable syringe on a white tray
Ready to use, in the evening before sleep per product instructions. Symbolic image.

Dosing

Dosing

Dosing, titration and syringe

Loading the dosing information …

  • Getting started and stepping up, drawn as a staircase
  • Units on the U-100 syringe for every step
  • How long one vial lasts

What the research shows

For sleep-promoting peptides the data is mixed (DSIP overview: Graf & Kastin, 1984). For the ready-made stack there is no separate study. Stay realistic: sleep hygiene is the base, a stack at most an add-on.

Study results

What the trials measured

Interactive: switch tabs, tap points, show or hide arms. Arms are named relative to each other, no dosing advice.

When DSIP acted in studies2

Hours after a slow injection into a vein, five small double-blind studies by one research group

Until sleepiness2 Latency of sleep induction
DSIP into a vein (human studies) 1 h
Duration up to2 longest duration observed
DSIP into a vein (human studies) 20 h

Values for DSIP alone, given into a vein. Whether Sleep Blend SZ352 contains DSIP is not stated in the lexicon. There are no measurements for the stack.

Petri dish under a microscope holding a glass brain next to a glass crescent moon
There is no study on the ready-made stack, only DSIP has been studied. Symbolic image.

Research status

Where the research stands

There is no registered trial on the stack itself. The registry also finds none on DSIP, the example from the entry. As of 26 Oct 2026.

  1. Preclinical DSIP: sleep studies in rabbits, rats and mice
  2. Phase 1 no registered trial
  3. Phase 2 no registered trial
  4. Phase 3 no registered trial
  5. Approval not yet
Not approved, neither the stack nor DSIP. ChEMBL lists DSIP (emideltide) with phase 2 as the highest phase, without an approval year.7

So far there is no registered trial in humans.

Side effects

  • Possible daytime drowsiness if dosed too late or too high.
  • Varies between individuals.

Storage

Store cool, dry and protected from light, out of reach of children. Keep the original packaging closed and mind the expiry date.

Four glass vials with golden contents on a white shelf, next to a folded light blue cloth
Cool, dry and protected from light, original packaging closed. Symbolic image.

Related

Related compounds

Same goals or a different path: all in the TPD lexicon.

Sleep Blend SZ352
DSIP Example peptide from the entry, single entry in the lexicon Relaxation PM Ready-made evening stack for winding down Epitalon Linked to the sleep and melatonin rhythm Selank Peptide for inner restlessness, without sedation

FAQ

Common questions about Sleep Blend SZ352

Short answers, each backed by the sources below.

Are there studies on Sleep Blend SZ352?

No. As of 26 October 2026 there is no study on the ready-made stack, neither on ClinicalTrials.gov nor in PubMed. The entry places it via single sleep-promoting peptides and names DSIP as an example.78

What is in Sleep Blend SZ352?

According to the lexicon several components to promote falling and staying asleep in one ready-to-use product. The entry does not name which compounds are included or in what amounts. That is why no study on a single component can be safely applied to the stack.

What is DSIP?

The delta sleep-inducing peptide is a nonapeptide of nine amino acids. It was isolated from rabbit blood in 1977 and named for its ability to induce deep sleep. In rabbits, rats and mice it mainly promoted delta sleep. Its own gene, a precursor protein or a receptor have not been found to this day.16

Does DSIP help with sleep in studies?

The data are mixed. One research group found better sleep in small double-blind studies, for example in 14 people with chronic insomnia over 7 nights. An independent double-blind study with 16 people saw only weak effects, partly explained by chance changes in the placebo group. The authors expected no major benefit. The effect also followed a U-shaped curve: more was not better.341

How fast and how long did DSIP act?

In the human studies DSIP was given slowly into a vein. Sleepiness began after about one hour and the effect lasted up to 20 hours. After four doses in a row sleep normalised in these studies. There are no such measurements for Sleep Blend SZ352.2

Does age matter in the DSIP studies?

In a study with 18 people with chronic insomnia the younger ones (29 to 59 years) slept normally by the end of the dosing week. In the older ones (60 to 83 years) the disturbance was twice as severe at the start and the immediate effect larger, but sleep was normal only after another week. The stronger the disturbance, the stronger the effect.5

Which side effects are known?

There are no study data for the stack. The entry names possible daytime drowsiness when given too late or too much. In the early DSIP studies tolerability was rated as good, there are no frequencies or long-term data.2

Is Sleep Blend SZ352 approved?

No. Neither the stack nor DSIP is approved as a medicine. ChEMBL lists DSIP under the name emideltide with phase 2 as the highest phase. Everything here is the state of research, not a recommendation.9

Glossary

Terms explained briefly

Dotted words in the text open these explanations directly.

Deep sleep
The sleep stage with slow delta waves in the EEG. It is the hardest stage to wake from.
Double-blind
Neither participants nor researchers know who gets the compound or placebo. That way expectations influence the result less.
DSIP
Delta sleep-inducing peptide, a nonapeptide. In animal studies it mainly promoted deep sleep, in humans the data are mixed.
Nervous system
Brain, spinal cord and nerves. Calming agents dampen its activity.
Nonapeptide
A peptide made of exactly nine amino acids.
Placebo
Dummy preparation without active substance. Comparing against it shows what is due to the substance itself.
Sedating
Dampening and making drowsy. Two sedating agents together add up.
Sleep hygiene
Habits around good sleep: fixed times, a dark and cool room, little caffeine and alcohol in the evening.
Sleeping pill
Medicine that deliberately induces sleep. Many act strongly and can cause dependence.
Stack
Several compounds combined in one product. The proportions are fixed.

Evidence

Sources

Show all 9 sourcesHide sources 6 Studies1 Trial registry2 Database checked 26 Oct 2026

Studies

  1. Review of DSIP: sleep and other effects

    Graf & Kastin, Neuroscience & Biobehavioral Reviews, 1984

    DOI 10.1016/0149-7634(84)90022-8 PMID 6145137
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  2. Five double-blind studies of DSIP in humans

    Schneider-Helmert & Schoenenberger, Neuropsychobiology, 1983

    DOI 10.1159/000117964 PMID 6689058
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  3. DSIP in severe chronic insomnia, 7 nights

    Schneider-Helmert, European Neurology, 1987

    DOI 10.1159/000116143 PMID 3622582
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  4. Double-blind study of DSIP in chronic insomnia

    Bes et al., Neuropsychobiology, 1992

    DOI 10.1159/000118919 PMID 1299794
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  5. DSIP in chronic insomnia, middle-aged and elderly

    Schneider-Helmert, European Neurology, 1986

    DOI 10.1159/000116050 PMID 3792404
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed
  6. DSIP, a still unresolved riddle (review)

    Kovalzon & Strekalova, Journal of Neurochemistry, 2006

    DOI 10.1111/j.1471-4159.2006.03693.x PMID 16539679
    Checked 26 Oct 2026 via doi.org, Crossref, PubMed

Trial registry

  1. Registry search for the stack and for DSIP (0 results)

    ClinicalTrials.gov, U.S. National Library of Medicine

    Checked 26 Oct 2026 via ClinicalTrials.gov API v2

Database

  1. PubMed search for the stack (0 results)

    PubMed, U.S. National Library of Medicine

    Checked 26 Oct 2026 via PubMed E-utilities
  2. DSIP (emideltide) in ChEMBL

    ChEMBL, EMBL-EBI (CHEMBL2104403)

    Checked 26 Oct 2026 via ChEMBL

In the shop

Sleep Blend SZ352 in the catalog

Sizes, prices and shipping times are on the product page.

To the product