Oxytocin

FDA-approved (prescription) Evidence grade A — regulator-approved with pivotal randomised trials Updated 2026-10-20

This page describes published research and public regulatory records. It is not medical advice. SoluneFit does not sell, supply, or recommend any compound. The SoluneFit app includes a private, on-device tracker for people who want a record of what they and their clinician have already decided — the app neither suggests compounds nor doses.

Also known as: Pitocin, Syntocinon, OT.

Regulatory status

FDA-approved injection (Pitocin) for medically indicated induction/augmentation of labour, incomplete abortion and postpartum haemorrhage; not indicated for elective induction [1]. No intranasal oxytocin product is approved in the US; intranasal use is off-label/research [2][3].

What it is

Nonapeptide posterior-pituitary hormone (synthetic).

The hormone that drives uterine contraction and milk let-down. In the US it is approved only as an injection (Pitocin) for medically indicated labour induction and postpartum bleeding; intranasal use for social or psychiatric effects is off-label and experimental.

What the published research shows

Grade A for the obstetric label uses. Intranasal use is grade B at best: the largest RCT (290 children/adolescents with autism) was null.

Published human studies and reports (these describe trial populations, not SoluneFit claims):

Labour induction or augmentation (Pitocin label): IV infusion only, in hospital: start 0.5-1 mU/min, increase by 1-2 mU/min every 30-60 min; rates above 9-10 mU/min are rarely needed at term.
Postpartum bleeding (Pitocin label): IV: 10-40 units in up to 1000 mL of diluent (maximum 40 units per 1000 mL); or IM 10 units after delivery of the placenta.
Autism spectrum disorder, ages 3-17 (Sikich et al. 2021 NEJM RCT): Intranasal oxytocin, target total 48 IU/day, versus placebo for 24 weeks in 290 randomised participants; no difference in the primary social-withdrawal score (difference -0.2, P=0.61).
Intranasal pharmacokinetics (Striepens et al. 2013): Single 24 IU intranasal dose in 11 healthy adults (4 placebo): plasma peak at about 15 min; CSF rise took up to 75 min; plasma and CSF levels were not correlated.

Mechanism, as reported

Binds oxytocin receptors on uterine smooth muscle to increase the strength and frequency of contractions, and on breast myoepithelial cells to eject milk; central effects on social behaviour are studied but not established as a treatment.

Practical record

Elimination half-life: 0.05 h (confidence: high). Label: plasma half-life about 1-6 minutes (IV), shorter in late pregnancy and during lactation; 0.05 h (3 min) used here. After 24 IU intranasal, plasma peaked at about 15 min and fell by 75 min (n=11).
Studied routes: intravenous, intramuscular, intranasal.
Typical supply: Rx: 10 units/mL solution for injection (Pitocin). Intranasal sprays used in trials are not marketed in the US.
Reconstitution: Injection is diluted in IV fluid per label; not reconstituted.
Storage: Pitocin label: 20-25 °C.

Safety signals on record

Reported adverse events: Label: uterine hypertonicity, tetanic contraction and rupture; water intoxication (convulsions, coma, rarely death) with prolonged high-dose infusion; anaphylaxis, arrhythmia, hypertensive episodes, nausea/vomiting, postpartum haemorrhage; fetal bradycardia, low Apgar score, neonatal seizures and retinal haemorrhage.
Contraindications: Label (antepartum): significant cephalopelvic disproportion, unfavourable fetal position, obstetric emergencies favouring surgery, fetal distress without imminent delivery, hypertonic uterus, conditions where vaginal delivery is contraindicated (e.g. placenta praevia, cord prolapse), hypersensitivity.
Interactions: Not detailed in the sections read; the label restricts use to hospital with medical supervision. UNVERIFIED: specific interactions (e.g. vasoconstrictors, anaesthetics).
Notes: Intranasal oxytocin bought outside a trial is unregulated; the US Syntocinon nasal spray is reported to have been withdrawn by its maker in the 1990s, but no FDA source was found (UNVERIFIED). A boxed warning was not confirmed in the label text read.

Sources

General wellness education, not medical advice. Unapproved compounds have no established dosing, purity standard, or safety profile.

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