Isoxsuprine it is used in humans for treatment of premature labor, i.e. a tocolytic, and as a vasodilator for the treatment of cerebral vascular insufficiency, Raynaud's phenomenon, and other conditions.Isoxsuprine may increase the heart rate, cause changes in blood pressure, and irritate the GI tract.It should therefore be used with caution if combined with other drugs that affect blood pressure, such as sedatives and anesthetic drugs.soxsuprine may increase the heart rate, cause changes in blood pressure, and irritate the GI tract. It should therefore be used with caution if combined with other drugs that affect blood pressure, such as sedatives and anesthetic drugs.