DSIP
Also referenced as: Delta sleep-inducing peptide
A nonapeptide isolated from rabbit brain in the 1970s, still discussed for sleep despite inconsistent evidence.
- Evidence grade
- DPreclinical Research
Preclinical Research
- Regulatory status
- Not FDA Approved
- Human data
- Limited
No registered clinical trials identified
- Last reviewed
- September 1, 2026
Overview
DSIP was isolated from the cerebral venous blood of sleeping rabbits and named for its apparent ability to induce delta-wave sleep.
Subsequent human work produced inconsistent results, and the compound never entered clinical use. It remains a good case study in how an evocative name outlives the evidence.
Why It's Being Studied
- Sleep architecture and delta-wave activity.
- Chronic pain and withdrawal syndromes in older clinical reports.
- Stress hormone and circadian regulation.
Mechanism of Action
It was found in the blood of sleeping animals and appeared to promote deep sleep, though later studies did not confirm a reliable effect.
Mechanistic proposals include modulation of somatostatin and corticotropin-releasing hormone signalling, effects on delta-wave EEG activity, and interaction with opioid and stress-axis pathways. No receptor has been definitively identified.
Research Areas & Routes Studied
- Sleep architecture
- Stress hormones
- Pain
- Subcutaneous injection (research)
- Intravenous (older clinical studies)
Evidence Summary
Older human studies exist but are small, inconsistent and decades old; the bulk of the literature is animal and mechanistic.
Human clinical evidence
- Small studies from the 1980s and 1990s reported effects on sleep latency and chronic pain; results were inconsistent and not replicated in modern trials.
Animal studies
- EEG and behavioural studies in rodents and rabbits.
Anecdotal / community information
- Community sleep reports are uncontrolled and subject to strong placebo effects.
Reported Adverse Events in Research
- Limited safety data; older studies reported few adverse events in small samples.
Limitations of Current Evidence
- Evidence is old, small and inconsistent.
- No established human dosing protocol exists.
Why It Is Used
- Sleep
Sleep Onset and Sleep Depth
Delta sleep-inducing peptide has the most promising name and some of the thinnest evidence on this site. That contrast is instructive.
Read the case study
Research References
- Narrative review
Delta sleep-inducing peptide: physiological and clinical studies