Description: Atosiban is an inhibitor of the hormones oxytocin and vasopressin. It is used as an intravenous medication as a labour repressant (tocolytic) to halt premature labor. Although initial studies suggested it could be used as a nasal spray and hence would not require hospital admission, it is not used in that form. It was developed by Ferring Pharmaceuticals in Sweden and first reported in the literature in 1985. Originally marketed by Ferring Pharmaceuticals, it is licensed in proprietary and generic forms for the delay of imminent pre-term birth in pregnant adult women.