What Is DSIP?
DSIP (delta sleep-inducing peptide) is a naturally occurring nine-amino-acid peptide, first isolated from rabbit brain venous blood in the 1970s and named for its apparent ability to promote slow-wave (“delta”) sleep. It has since been investigated for roles in sleep regulation, stress, and neuroendocrine signalling, and is sold in nootropic/peptide circles as a sleep aid. It is not an approved medicine or dietary supplement. Despite decades of interest, its biology remains poorly defined — no DSIP gene, precursor, or dedicated receptor has been conclusively identified, which is a major reason the “sleep peptide” hypothesis stayed unresolved.
Evidence
The DSIP evidence base is old, small, and inconclusive. A 2006 review in the Journal of Neurochemistry characterised DSIP as a “still unresolved riddle,” noting that the link between DSIP and sleep has never been firmly established and that the sleep-factor hypothesis is poorly documented, partly because the peptide’s gene, precursor, and receptor have not been isolated 1Reference 1ReviewDelta sleep-inducing peptide (DSIP): a still unresolved riddle — reviewView study →. Early human work is limited to small studies: a double-blind crossover study in six healthy volunteers reported that intravenous DSIP increased sleep and shortened sleep onset without producing classic pharmacologic sedation 2Reference 2Clinical trialAcute and delayed effects of DSIP (delta sleep-inducing peptide) on human sleep behavior — human studyView study → — an interesting but very small and dated finding. No modern, adequately powered randomised trial establishing DSIP as an effective sleep aid was found in this pass, so claims that DSIP reliably improves sleep in people should be regarded as unproven.
Dosage & Safety
There is no established human therapeutic dose for DSIP; the small historical studies used intravenous infusions in research settings (e.g. on the order of 25 nmol/kg) that are not a consumer regimen, and this page makes no dosing recommendation 2Reference 2Clinical trialAcute and delayed effects of DSIP (delta sleep-inducing peptide) on human sleep behavior — human studyView study →. DSIP is not FDA-approved and is not an approved dietary supplement. Human safety in the small early studies appeared unremarkable, but modern, repeat-dose, and long-term safety data, drug interactions, and pregnancy/lactation safety are not established and were not assessed in this pass. This entry is informational only and is not an endorsement of use.
References
- Kovalzon VM, Strekalova TV. (2006). Delta sleep-inducing peptide (DSIP): a still unresolved riddle — review. J Neurochem. https://pubmed.ncbi.nlm.nih.gov/16539679/
- Schneider-Helmert D, Gnirss F, Monnier M, et al. (1981). Acute and delayed effects of DSIP (delta sleep-inducing peptide) on human sleep behavior — human study. Int J Clin Pharmacol Ther Toxicol. https://pubmed.ncbi.nlm.nih.gov/6895513/