What DSIP is
Delta sleep-inducing peptide is one of the odder stories in the catalog: discovered in 1977 from rabbit brain during slow-wave sleep, studied in small human trials in the 1980s with mixed results, then largely abandoned by mainstream research. Even its endogenous existence as a discrete peptide is debated. It persists in the community as a pre-bed injection for deeper sleep, with anecdote carrying most of the weight.
What we do not know
- The mechanism was never elucidated. Fifty years on, it is still unclear what receptor or pathway it acts through.
- The human literature is small, from the 1980s, and largely uncontrolled. Research essentially stopped in the 1990s and no modern trials exist.
- No published human pharmacokinetics, and no basis for any particular dose or route.
Reconstitution math
Concentration is everything: the same 5 mg vial gives a different draw for every amount of bacteriostatic water you add. The table uses the common 2 mL setup for each vial size, which puts every unit on a U-100 insulin syringe at 25 mcg for the default vial. Dashes mark draws too small to measure or larger than the syringe.
| Vial | BAC water | Concentration | 100 mcg | 250 mcg | 500 mcg |
|---|---|---|---|---|---|
| 2 mg | 2 mL | 1 mg/mL | 10 u | 25 u | 50 u |
| 5 mg | 2 mL | 2.5 mg/mL | 4 u | 10 u | 20 u |
Dosing and protocol
Community protocol: 100 to 500 mcg subcutaneously 30 to 60 minutes before bed, nightly or as needed.
Community dosing runs 100 to 500 mcg subcutaneously before bed. On a 5 mg vial with 2 mL of water, 250 mcg is a 10-unit draw. Some users dose nightly, others only on disrupted-sleep nights; there is no clinical schedule to anchor either pattern.
Pharmacokinetics
No curve is shown, on purpose.
DSIP was studied in humans in the 1980s by intravenous infusion, and those old studies suggest clearance within minutes. No subcutaneous pharmacokinetics were ever characterized, and the IV data is too old and too different in route to plot honestly.
How it is thought to work
A nonapeptide isolated in the 1970s from the cerebral venous blood of rabbits in induced sleep. Despite the name, a mechanism was never clearly established, and it is not a straightforward sedative.
What the evidence supports
This table grades how well each outcome has been studied in humans, not how well DSIP works. A strong grade means the question was asked properly, and the answer may still have been negative. Nothing here is inherited from a drug class, a close analog, or the parent molecule of a fragment.
| Outcome | Strongest published evidence |
|---|---|
| Chronic pain | Human, observational |
| Sleep onset in insomnia | Human, observational |
| Modern replication of any 1980s result | No data |
Storage and handling
Lyophilized vials keep best cold, dark, and dry; refrigeration is the community default and freezing lyophilized powder is common for long holds. After reconstitution, refrigerate at 2 to 8 C, do not freeze the solution, and date the vial. Bacteriostatic water's preservative keeps multi-dose use practical for about 28 days by USP convention, though our 120-day stability study found the preservative itself outlasts that window.
Got a certificate of analysis with your vial? Run it through our COA Reader: it reads the report in plain English, checks purity and mass against the label claim, and links the testing lab’s own verification page. Our guide to reading a COA explains what the numbers do and do not tell you.
Sources
- Graf and Kastin, Delta-sleep-inducing peptide (DSIP): a review, Neurosci Biobehav Rev 1984PMID 6145137 · DOI
- Schneider-Helmert, DSIP in sleep disturbances, Eur Neurol 1986PMID 3758119 · DOI