Atosiban
Atosiban dosing, mechanism of action, side effects, and clinical evidence. Complete reference for healthcare professionals.
Hormone OptimizationIntravenous (Tractocile)6.75mg IV bolus then infusion
Overview
Atosiban is a competitive oxytocin and vasopressin V1a receptor antagonist used to delay imminent preterm labor.
Mechanism of Action
- Oxytocin receptor blockade — Inhibits oxytocin-mediated uterine contractions
- V1a receptor blockade — Additional tocolytic effect
- Uterine relaxation — Reduces frequency and intensity of contractions
Dosing
6.75mg IV bolus, followed by 300mcg/min for 3 hours, then 100mcg/min for up to 45 hours.
Status
Approved in EU and many countries. Not FDA-approved in the US.
Last updated: 2026-03-27