Published · 5 references
DSIP vs Epitalon
DSIP and Epitalon are different molecules: DSIP is a nine-residue peptide first purified from rabbit blood, and Epitalon is a four-residue peptide designed from the composition of a bovine extract.
Structure at a glance
DSIP · 9 residues
Epitalon · 4 residues
Letters are one-letter amino acid codes.
Drawn from the product database. Each measure's bars share one scale.
| Property | DSIP | Epitalon |
|---|---|---|
| What it is | A nine-residue peptide. In the founding study, it was purified from a dialysate of cerebral venous blood from rabbits under electrical stimulation of the thalamus.[1] | A four-residue peptide, designed from the amino acid composition of Epithalamin, a bovine pineal gland extract.[2] Also written Epithalon. |
| How they relate | Different molecules. DSIP's founding study purified it from a dialysate of cerebral venous blood from rabbits under electrical stimulation of the thalamus.[1] Epitalon was designed from the amino acid composition of Epithalamin, a bovine extract.[2] | |
| CAS number | 62568-57-4 | 307297-39-8 |
| Molecular formula | C35H48N10O15 | C14H22N4O9 |
| Molecular weight | 848.81 g/mol | 390.35 g/mol |
| Sequence | WAGGDASGE | AEDG |
| Evidence base | Human studies. Also animal and in vitro research. Limits in the literature reviewed for DSIP: small samples, weak design by present standards and failed replication. | FDA's literature search found three human studies.[3] The strongest of them did not specify blinding.[3] Also animal and in vitro studies. One research group produced almost all of the literature. |
| Regulatory status | The FDA has not approved DSIP for human use. | The FDA has not approved Epitalon for human use. A US orphan drug designation was granted in 2010 and withdrawn or revoked in 2016.[3] Designation is not approval. |
| Compared head-to-head? | No direct comparison found in PubMed (searched October 2026).[4] | |
| Handling difference | Neither contains a cysteine or a methionine. DSIP's primary weak point is its tryptophan, which oxidizes on exposure to air and light. Epitalon's is an aspartate followed by glycine, which can rearrange to isoaspartate. | |
How DSIP and Epitalon differ
DSIP and Epitalon are different molecules. DSIP is a synthetic nine-residue peptide, and Epitalon is a synthetic four-residue peptide. DSIP stands for delta sleep-inducing peptide. That name records what its discoverers sought in the 1970s, not a replicated finding.
In the founding animal study, DSIP was purified from a dialysate of cerebral venous blood from rabbits under electrical stimulation of the thalamus.[1] Whether DSIP occurs as such in the human body is unresolved, with no gene or precursor identified. Epitalon was designed from the amino acid composition of Epithalamin, a bovine extract.[2]
Because Epithalamin is an undefined animal-tissue mixture and Epitalon one defined synthetic molecule, a result for one is not a result for the other. For DSIP, most human reports of the peptide in plasma, brain, gut or milk measure DSIP-like immunoreactivity. That is antibody binding, not identification of the peptide. A gene aliased DSIPI has the official symbol TSC22D3, and a structural study shows its product in pigs does not contain the DSIP sequence.[5] Evidence about that protein is not evidence about DSIP. In animal work, results obtained with protease-resistant analogs of DSIP are not DSIP results.
DSIP has been tested in human studies. In the literature reviewed for DSIP, the limits are small samples, weak design by present standards and failed replication. For Epitalon, FDA's literature search found three human studies, and the strongest of them did not specify blinding.[3] One research group produced almost all of the literature on Epitalon. Independent replication in other laboratories has been limited.
The FDA has not approved DSIP or Epitalon for human use.
Neither peptide contains a cysteine or a methionine, and both carry a net negative charge. DSIP's primary weak point is its single tryptophan, whose indole ring oxidizes readily on exposure to air and light. Epitalon contains no aromatic residue. Its weak point is an aspartate followed by glycine, which can close to a succinimide ring and reopen as isoaspartate at unchanged mass. Solid-phase synthesis delivers each as a salt, usually trifluoroacetate or acetate.
Have DSIP and Epitalon been compared directly?
No direct comparison of DSIP and Epitalon was found in a PubMed search run in October 2026.[4] That search covers PubMed only.
Read more on each compound
DSIP
Frequently Asked Questions
Is DSIP the same as Epitalon?+−
DSIP and Epitalon are different molecules: DSIP is a nine-residue peptide, and Epitalon is a four-residue peptide. In its founding animal study, DSIP was purified from rabbit blood. Epitalon was designed from the amino acid composition of Epithalamin, a bovine extract.
References
- 1Schoenenberger GA, Maier PF, Tobler HJ, Wilson K, Monnier M. Pflugers Arch. 1978;376(2):119-29. PMID 568769.
- 2Araj SK, Brzezik J, Madra-Gackowska K, Szeleszczuk L. International Journal of Molecular Sciences. 2025;26(6):2691. PMID 40141333.
- 3US Food and Drug Administration, Center for Drug Evaluation and Research. Briefing Document, Pharmacy Compounding Advisory Committee, July 2026. fda.gov
- 4PubMed search via NCBI E-utilities, run 3 October 2026; records entered to 2 October 2026. Query: ("DSIP"[tiab] OR "delta sleep-inducing peptide"[tiab] OR "emideltide"[tiab]) AND ("epitalon"[tiab] OR "epithalon"[tiab] OR "epithalone"[tiab] OR "epitalone"[tiab]) AND ("1800/01/01"[edat] : "2026/10/02"[edat]). 2 records; none was a direct comparison of the two compounds.
Related comparisons
Epitalon vs N-Acetyl Epitalon
N-Acetyl Epitalon is a chemically modified form of Epitalon: the same four residues, with an N-terminal acetyl group and a C-terminal amide.
Read ComparisonEpitalon vs Pinealon
Epitalon and Pinealon are different molecules: a synthetic four-residue peptide and a synthetic three-residue one.
Read ComparisonSelank vs Semax
Selank and Semax are different seven-residue peptides: the same three-residue C-terminal extension, on tuftsin and on an ACTH core.
Read Comparison