Oxytocin is an endogenous cyclic nonapeptide hormone (Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2 with a disulfide bridge between Cys1 and Cys6, MW ~1007.2 g/mol) produced in the hypothalamus and released from the posterior pituitary. Synthetic oxytocin (Pitocin) is one of the most widely used medications in obstetrics, FDA-approved for labor induction and augmentation, and for control of postpartum hemorrhage. It acts on oxytocin receptors in the uterine myometrium to stimulate rhythmic contractions and on mammary myoepithelial cells to facilitate milk ejection.
10 vendors tracked by PeptideAtlas list Oxytocin, priced from $25.00 to $59.99. The lowest price per milligram is $2.80/mg at All Peptides USA (10mg). 1 independent Janoshik purity test cover Oxytocin across 1 vendor.
Category: Reproductive / Hormonal. Evidence rating: A (strong human clinical data).
Clinical status: FDA-approved (Pitocin for labor induction, augmentation of labor, and postpartum hemorrhage)
Oxytocin binds to the oxytocin receptor (OXTR), a Gq/11-coupled GPCR expressed in uterine myometrium, mammary tissue, and the central nervous system. Receptor activation triggers phospholipase C-mediated hydrolysis of PIP2 to IP3 and DAG, causing intracellular calcium release from the sarcoplasmic…
Research base: 0 registered clinical trials and 12 indexed publications reference Oxytocin.
Safety considerations: Uterine hyperstimulation/tachysystole: can cause excessive contractions leading to fetal distress; requires continuous fetal monitoring; Water intoxication and hyponatremia: oxytocin has antidiuretic properties at high doses; risk increases with prolonged infusion and hypotonic IV fluids; Uterine rupture: rare but life-threatening, especially in patients with prior uterine surgery.
Reviewed by the PeptideAtlas Editorial Team.
| Amino-acid sequence | Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2 (disulfide bridge Cys1-Cys6) |
|---|---|
| Molecular formula | C43H66N12O12S2 |
| Molecular weight | ~1007.2 g/mol |
| CAS number | 50-56-6 |
| Half-life | ~1-6 minutes (IV) |
| Bioavailability | ~2-5% intranasal |
| Production method | synthetic |
| Anti-doping status | not-listed |
| US regulatory status | FDA-approved (Pitocin). Used for labor induction, augmentation, and postpartum hemorrhage management. |
| Vendor | Size | Price | Price per mg |
|---|---|---|---|
| All Peptides USA | 10mg | $28.00 | $2.80/mg |
| PureRx Peptides | 10mg | $42.00 | $4.20/mg |
| Mammoth Muscle Peptides | 5MG | $25.00 | $5.00/mg |
| Peplogix Peptides | 10mg | $50.00 | $5.00/mg |
| Protide Health | 10mg | $55.00 | $5.50/mg |
| Ameano Peptides | 10mg | $58.00 | $5.80/mg |
| Compound Sciences | 10mg | $59.99 | $6.00/mg |
| Astra Peptides | 5MG | $34.99 | $7.00/mg |
| Wholesale Peptide | 2mg | $28.04 | $14.02/mg |
| Orbitrex Peptides | 2mg | $34.99 | $17.50/mg |
| Vendor | Best tested purity |
|---|---|
| Peptide Gurus | 97.5% |
Related peptides: Kisspeptin, Gonadorelin, Vasopressin.
Pitocin is the brand name for synthetic oxytocin given intravenously in hospitals. It is primarily used to induce labor when medically necessary (e.g., post-dates pregnancy, preeclampsia), to augment slow labor, and to prevent or treat postpartum hemorrhage by promoting uterine contraction after delivery.
Despite initial promising small studies, the largest randomized trial (SOAR, NEJM 2021, n=290) found no benefit of 24 weeks of intranasal oxytocin over placebo for social functioning in children and adolescents with autism. The evidence does not support routine use for social enhancement.
Intranasal oxytocin has been used off-label to facilitate the milk let-down reflex, but Cochrane reviews found insufficient evidence to recommend routine use. It may be considered in select cases of documented let-down difficulties under medical supervision.
The main risks include uterine hyperstimulation (excessive contractions that can compromise fetal oxygen supply), water intoxication with prolonged high-dose infusion, and rarely uterine rupture. Continuous fetal heart rate monitoring is required during oxytocin administration.
Vendors stocking it: Direct Peptides UK, Zztai Peptide, All Peptides USA, Grey Axis Research, Ultima Pharmaceuticals, Ameano Peptides, Mammoth Muscle Peptides, Compound Sciences, Wholesale Peptide, Peplogix Peptides, Modern Peptides, Charleston Peptide Supply, Astra Peptides, PureRx Peptides, Discovery Research USA, Grewo Peptide, Protide Health, utherpeptide, Uther, Disguised Alpha, Toronto Peptides, Montreal Peptides, Orbitrex Peptides, Wuhan HongyouJie HYJ, BPX Research.
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