Compare prices and buy Oxytocin from 25 research peptide vendors - also called suppliers or sources. Updated daily.
A cyclic nine-residue neurohypophyseal hormone (C43H66N12O12S2, CAS 50-56-6) with a disulfide bridge between Cys1 and Cys6. Made mainly in the paraventricular and supraoptic hypothalamic nuclei and released from the posterior pituitary, it acts on the oxytocin receptor (OXTR) to drive uterine contraction and milk ejection. FDA-approved as Pitocin and other oxytocin injections for medically indicated labor induction, labor stimulation and postpartum bleeding. Its links to social behavior rest mainly on animal studies.
For research purposes only. Not medical advice.
Oxytocin is a nine-residue peptide hormone, Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH2 (C43H66N12O12S2). A disulfide bond between the cysteines at positions 1 and 6 closes a six-residue ring, and the chain ends in glycinamide. Vincent du Vigneaud worked out its sequence in 1953 and also synthesized it, work his 1955 Nobel Prize in Chemistry cited as the first synthesis of a polypeptide hormone. Oxytocin differs from vasopressin at only two amino acid positions, which the Pitocin label offers as the likely reason it has some pressor and antidiuretic activity.
The hormone is made mainly in magnocellular neurons of the hypothalamic paraventricular and supraoptic nuclei and released from the posterior pituitary. Its receptor, OXTR, is a G protein-coupled receptor that signals mainly through Gq and phospholipase C-beta. The classical actions are uterine contraction during labor and milk ejection during lactation. Uterine receptor levels rise greatly during pregnancy and peak in early labor at term, and the label puts the plasma half-life at about 1 to 6 minutes.
As of October 2026, oxytocin injection is FDA-approved as Pitocin (Par Health, NDA 018261) and under its nonproprietary name from Fresenius Kabi, Hikma and Sagent. The Pitocin label lists four uses:
A boxed notice states that Pitocin is not indicated for elective induction because the available data are inadequate to weigh benefits against risks. The label also describes uterine rupture with excessive dosage and water intoxication from the antidiuretic effect, including reported maternal deaths.
Those approvals, and not the bulk-substance nominations that decide most research peptides, set oxytocin's regulatory status. Under section 503A, a bulk substance depends on FDA's bulks list only when it has no USP monograph and is not a component of an approved drug. Oxytocin appears in neither table of FDA's Category 2 page (updated April 2026). A nasal spray, Novartis's Syntocinon, also held a US approval until FDA withdrew its approval in 1997 at Novartis's request, after the product had left the market.
Animal studies, mostly in rodents, link central oxytocin signaling to parental behavior, social bonding and individual recognition. That preclinical work inspired a large, contested human literature on intranasal oxytocin. Walum, Waldman and Young (Biological Psychiatry, 2016) estimated average statistical power of 16% for intranasal studies in healthy people and 12% for clinical trials, and concluded that most published findings probably do not represent true effects. In children and adolescents with autism, the NIH-funded SOARS-B trial (NEJM, 2021) found no significant difference from placebo on its primary social-withdrawal measure over 24 weeks (modified intention-to-treat analysis).
Delivery to the brain is a separate question. Cerebrospinal fluid levels rose after intranasal administration in a small human study (Striepens, Scientific Reports, 2013), but its assay could not distinguish administered from endogenous oxytocin. In six rhesus macaques given deuterium-labeled oxytocin, Lee and colleagues (Molecular Psychiatry, 2018) detected the labeled peptide in cerebrospinal fluid after both nasal and intravenous dosing, with no advantage for the nasal route, a preclinical result.
Carbetocin (C45H69N11O12S) is an oxytocin analog whose PubChem synonym, deamino-2-O-methyltyrosine-1-carbaoxytocin, spells out three changes: the N-terminal amine is removed, a methylene replaces one sulfur of the disulfide bridge, and the tyrosine is O-methylated.
The CHAMPION trial (NEJM, 2018), run under WHO oversight with MSD for Mothers funding, randomized 29,645 women in 10 countries to heat-stable carbetocin or oxytocin immediately after vaginal birth. In the modified intention-to-treat analysis, blood loss of at least 500 ml or use of additional uterotonic drugs occurred in 14.5% versus 14.4% (relative risk 1.01), consistent with noninferiority. For blood loss of at least 1000 ml (1.51% versus 1.45%), noninferiority was not shown, a shortfall the authors link to low event rates. Carbetocin has no FDA approval as of October 2026.
Vendor titles use "Oxytocin", "Oxytocin Acetate" and short codes such as OXTCN and Oxy. The acetate is a salt of the same peptide with its own CAS number (6233-83-6), and PeptideScouter lists both names on this page. The approved injections are standardized by oxytocic activity in USP units, while research vials are sold by the milligram, so the two are not labeled on the same scale. Nasal spray listings show a package price but no per-milligram figure, which PeptideScouter computes only for vials. Related endocrine peptides are on the hormonal category page.
Not as a product. Pitocin and the oxytocin injections sold under the drug's nonproprietary name are FDA-approved sterile solutions, standardized in USP units of oxytocic activity and labeled for medically indicated labor induction, labor stimulation and the control of postpartum bleeding. The Pitocin label notes that the hormone is prepared synthetically to avoid contamination with vasopressin. Research-grade oxytocin sold by peptide vendors is a separate material that the FDA has not approved. It is sold by the milligram and offered for laboratory research only, not for human consumption.
Yes. Novartis's Syntocinon nasal spray held new drug application 012285. The FDA withdrew that approval effective September 8, 1997, after Novartis told the agency the product was no longer marketed and asked for the withdrawal. As of October 2026, every oxytocin product with a current US marketing status in the FDA's Drugs@FDA database is an injection. Nasal sprays sold by research vendors are not Syntocinon. PeptideScouter computes a per-milligram price only for vials, so spray listings show a package price but are left out of per-milligram comparisons.
SOARS-B, published in the New England Journal of Medicine in 2021 and funded by the National Institute of Child Health and Human Development, randomly assigned 290 children and adolescents aged 3 to 17 with autism spectrum disorder to intranasal oxytocin or placebo for 24 weeks. In the modified intention-to-treat analysis of 277 participants, the primary outcome, a social withdrawal subscale of the Aberrant Behavior Checklist, fell by 3.7 points with oxytocin and 3.5 points with placebo. The difference of 0.2 points was not statistically significant (P = 0.61). Secondary measures of social function and an abbreviated IQ measure generally did not differ, and adverse events were similar in the two groups.
It is a salt form of the same peptide. PubChem lists oxytocin under CAS 50-56-6 (C43H66N12O12S2, molecular weight 1007.2) and oxytocin acetate, a 1:1 salt with acetic acid, under CAS 6233-83-6 (C45H70N12O14S2, molecular weight 1067.2). In that salt the peptide makes up about 94% of the mass, so a quantity stated for the acetate refers to the salt unless the vendor says it is the free peptide. The CAS number shown for this page is the free peptide's, and PeptideScouter lists both names here.
Carbetocin is a synthetic oxytocin analog. Compared with oxytocin, its N-terminal amine is removed, a methylene group replaces one sulfur of the disulfide bridge, and its tyrosine is O-methylated, giving the formula C45H69N11O12S. In the CHAMPION trial (New England Journal of Medicine, 2018) of 29,645 women, a heat-stable carbetocin formulation was noninferior to oxytocin for preventing blood loss of at least 500 ml or the use of additional uterotonic drugs after vaginal birth, in both its modified intention-to-treat and per-protocol analyses. Noninferiority was not shown for blood loss of at least 1000 ml. Carbetocin has no FDA approval as of October 2026, and Health Canada's drug product database lists Ferring's Duratocin as a marketed carbetocin product.
Oxytocin is sold by 25 research peptide vendors indexed on PeptideScouter, with 43 tracked listings compared per vendor in the table above. Pricing is normalized and refreshed daily.
22 of the 25 indexed vendors currently have Oxytocin in stock. The comparison table marks out-of-stock listings, and stock state is refreshed daily.
Peptide Titans currently lists Oxytocin at $3.50/mg, the lowest listed price across 25 tracked research peptide vendors. With current vendor discount codes applied, the lowest effective price is $2.97/mg.
Discount codes are issued per vendor rather than per peptide, so any code applies across that vendor's whole catalog. All 25 vendors listing Oxytocin publish a PeptideScouter code, worth 5% to 50% off. Applied, the lowest effective price falls from $3.30/mg listed to $2.97/mg at Studz Peptides. Each vendor's code is shown beside its price in the table above.
Oxytocin ranges from $3.30/mg to $22.00/mg across 43 listings from 25 research peptide vendors, normalized to USD per milligram and refreshed daily.
25 research peptide vendors currently list Oxytocin on PeptideScouter, with 22 in stock right now. We track 43 listings across size and kit variants.
Oxytocin's CAS Registry Number is 50-56-6. It is also sold as OXTCN, Oxytocin Acetate.
