Comparison
Oxytocin vs. Vasopressin
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
50-56-6
no data
Molecular weight
1007.19 g/mol
1084.23 g/mol
Half-life
0.05 h
no data
Sequence
Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2no data
Mechanism of action
Oxytocin
Oxytocin is synthesised in the hypothalamus and released via the posterior pituitary. Peripherally it binds the oxytocin receptor, a G-protein-coupled receptor, and through the phospholipase-C cascade and calcium release triggers contraction of uterine smooth muscle and milk ejection — the pharmacological basis of the obstetric approval. Centrally, oxytocin acts as a neuromodulator and has been linked to social bonding, trust and modulation of stress and anxiety circuits. Its central effects in humans are mechanistically incompletely understood, particularly because it is unclear to what extent peripherally or intranasally administered oxytocin crosses the blood-brain barrier.
Vasopressin
Vasopressin binds V1 receptors (vasoconstriction, raising vascular resistance) and V2 receptors (renal water reabsorption via aquaporin channels). This raises blood pressure and acts antidiuretically. Desmopressin is the V2-selective synthetic analog.
Evidence base
Highest evidence
Human RCT
Human RCT
Studies
4
0
of which in humans
4
0
Effects recorded
3
2
Open conflicts
1
0
Documented adverse events
0
1
Legal status
Full entries
Frequently asked questions
- What is the difference between Oxytocin and Vasopressin?
- Oxytocin is classified as "Research other", while Vasopressin is classified as "Research other". Oxytocin: Oxytocin is an endogenous nonapeptide hormone of the posterior pituitary. In synthetic form (Pitocin, Syntocinon) it has been approved for decades to induce and augment labour and to control postpartum uterine bleeding. Strictly separate from this is intranasal use to influence social behaviour, trust, anxiety or autism symptoms: this use is unapproved, purely experimental, and yields inconsistent and often negative results in controlled trials. Vasopressin: Vasopressin (arginine vasopressin, antidiuretic hormone/ADH) is a cyclic nonapeptide hormone that regulates water balance and vascular tone. As Vasostrict it is approved to raise blood pressure in vasodilatory shock. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Oxytocin or Vasopressin?
- The highest available evidence level is "Human RCT" for Oxytocin and "Human RCT" for Vasopressin. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of Oxytocin and Vasopressin in Germany and the United States?
- Germany: Oxytocin — Prescription, Vasopressin — Prescription. United States: Oxytocin — Prescription, Vasopressin — Prescription. These are factual summaries with source and review date on the individual pages.