Objective: Australasian guidelines for the treatment of over-anticoagulation have been published. We aimed to determine whether emergency department [ED] patients taking warfarin who have high INR were treated according to guidelines. Methods: This retrospective observational study included ED patients taking warfarin with INR ≥ 4. Data included demographics, warfarin indication, bleeding evidence and subsequent management. Outcome of interest was proportion treated according to guidelines; analysed by descriptive statistics. Results: 201 patients were studied; median age 74 years, 47% female. Atrial fibrillation was the main indication for warfarin [63%]. 48 patients [24%] presented with bleeding, of which 22 were classified as major bleeds. All patients with major bleeding received reversal treatment; with 64% receiving recommended triple therapy. 33% in the non-bleeding group received reversal treatment. Conclusion: There was reasonably good compliance with the guidelines, especially for patients with major bleeding. Vitamin K doses were suboptimal in a significant proportion of cases.