DSIP

DSIP (delta sleep-inducing peptide) is a nonapeptide (Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu) first isolated in 1977 by the Schoenenberger-Monnier group in Basel from the cerebral venous blood of rabbits during electrically induced slow-wave (delta) sleep. It was named for the early observation that infusing the peptide could increase delta-wave EEG activity in recipient animals, and it has since been studied for possible roles in sleep, stress regulation, pain, and modulation of various endocrine and autonomic functions. Despite nearly five decades of research, DSIP remains one of the more enigmatic neuropeptides: the gene, a definitive receptor, and a clear physiological pathway have not been firmly established, and findings across studies have been inconsistent. Some early small human studies reported benefits for insomnia, chronic pain, and withdrawal symptoms, but these were small, often uncontrolled, and have not been convincingly replicated in modern controlled trials. A frequently cited 2006 review described DSIP as a "still unresolved riddle." DSIP is not approved as a drug by the FDA, EMA, or other major regulators. It is sold online as a research chemical, typically labeled "for research use only." This entry summarizes the available science and community-reported practice for reference only; it is not medical advice and does not endorse human use.