Page data last changed: . Chemistry registry snapshot: . Registry refreshes and identity assessments are separate from scientific content review.
Cyclic nonapeptide with a disulfide bridge — classic neurohormone.
Part of the Neuropeptides & signaling cluster
Overview
Oxytocin is a nine-amino-acid neuropeptide and hormone involved in labor, lactation, and social behavior. It is a classic model of cyclic peptide structure.
Source & context
Biological / chemical source: Hypothalamus
Primary research or clinical context: Childbirth induction (clinical)
Sequence and ring
Oxytocin (CYIQNCPLG) forms a disulfide bridge between the two cysteine residues, creating a cyclic N-terminal region that is essential for receptor recognition.
Sequence
One-letter sequence commonly cited for Oxytocin (educational; isoforms and modifications may differ):
CYIQNCPLG
Residues plotted ~100° apart around an α-helix — clustering of one color reveals an amphipathic face.
Structure & chemistry
Molecular identity & reference confidence
Source-supported reference
Reference values are taken from the cited molecular record or curated profile. A database match is not independent laboratory verification; modifications, counter-ions, and formulations can change the measured mass.
- Molecular form
- Oxytocin (source record; form not independently established)
- Species
- Not established by this molecular identity audit
- Termini (N / C)
- Not specified / Not specified
Average reference mass
Reference policy updated: 2026-10-05
- IUPHAR/BPS source snapshot · 2026-10-01
- PubChem molecular record · 2026-10-01
- Molecular formula
- C43H66N12O12S2
- Average reference mass
- ≈ 1,007.2
- Status
- Approved medicine in at least one jurisdiction (IUPHAR record)
- PubChem CID: 439302
- IUPHAR ligand: 2174
- ChEMBL: CHEMBL395429
- DrugBank: DB00107
- CAS RN: 50-56-6
- UNII: 1JQS135EYN
Chemistry values: PubChem, IUPHAR/BPS Guide to Pharmacology · fetched 2026-10-01.
Clinical development snapshot
ClinicalTrials.gov lists 929 registered studies with “Oxytocin” as an intervention (snapshot 2026-10-01). A registry footprint is not evidence of efficacy or approval.
| NCT | Title | Phase | Status | Updated |
|---|---|---|---|---|
| NCT06757517 | Effects of Intranasal Oxytocin in the Treatment of Benzodiazepine Withdrawal: A Pilot RCT | Phase 2 | completed | 2026-09-28 |
| NCT04306354 | Use of Intranasal Oxytocin During Detoxification of Crack Cocaine | Phase 2 | completed | 2026-09-28 |
| NCT04373902 | Physiological-based Cord Clamping in Congenital Diaphragmatic Hernia | Not applicable | completed | 2026-09-25 |
| NCT07838493 | Oromucosal Oxytocin and Vasopressin Modulation of Emotional Face Attention | Not applicable | recruiting | 2026-09-24 |
| NCT07430228 | Efficacy of Intravenous Oxytocin to Speed Recovery After THA | Phase 2 | enrolling by invitation | 2026-09-24 |
| NCT06892977 | Mapping Stress and Pain Interactions (G072323N) | — | enrolling by invitation | 2026-09-21 |
Oxytocin — reconstitution calculator
Enter how much peptide is in the vial and how much diluent (e.g. bacteriostatic water) is added. The tool returns the resulting solution concentration — and, for any amount you type, the volume it corresponds to. This is educational arithmetic, not a dosing recommendation.
Reference form: Oxytocin (source record; form not independently established)Average reference mass: 1,007.2 Da
Enter an amount to see the volume it corresponds to.
Educational concentration mathematics only. This tool does not recommend a dose, amount, or protocol, and nothing here is medical advice. Many peptides are not authorized by Health Canada for human use — see our reconstitution and bacteriostatic-water guides for context.
Change log
Dated observations from the data pipeline (registry flags, trial footprints, identifiers) and editorial reviews of this profile.
- Trials4 registered studies added on ClinicalTrials.gov (now 929).
FAQ about Oxytocin
What is Oxytocin?+
Oxytocin is a nine-amino-acid neuropeptide and hormone involved in labor, lactation, and social behavior. It is a classic model of cyclic peptide structure.
What Canadian product status is recorded for Oxytocin?+
Health Canada lists OXYTOCIN INJECTION USP (DIN 00497398) as marketed (verified 2026-10-05). This status applies to those specific products and does not extend to every reagent, formulation or use of Oxytocin.
What is the typical length of Oxytocin?+
Oxytocin is commonly described as approximately 9 amino acids (Neuropeptide).
Related peptides
References & further reading
- 1.Uvnäs-Moberg (2024). The physiology and pharmacology of oxytocin in labor and in the peripartum period. Am J Obstet Gynecol
- 2.Carter et al. (2020). Is Oxytocin "Nature's Medicine"?. Pharmacol Rev
- 3.Uvnäs Moberg et al. (2020). Maternal plasma levels of oxytocin during breastfeeding-A systematic review. PLoS One
- 4.Valtcheva et al. (2023). Neural circuitry for maternal oxytocin release induced by infant cries. Nature
- 5.Zelmanoff et al. (2025). Oxytocin signaling regulates maternally directed behavior during early life. Science
- 6.Leng et al. (2008). Oxytocin and appetite. Prog Brain Res
- 7.Josselsohn et al. (2024). Oxytocin in neurodevelopmental disorders: Autism spectrum disorder and Prader-Willi syndrome. Pharmacol Ther
- 8.Marlin et al. (2015). Oxytocin enables maternal behaviour by balancing cortical inhibition. Nature
- 9.PubChem — compound summary for Oxytocin (CID 439302)
- 10.Wikipedia — Oxytocin