Autonomic dysreflexia is a potentially life-threatening condition that affects patients with a spinal cord injury at the level of T6 or above. It is characterised by uncontrolled elevation of systolic blood pressure of more than 20mmHg, which may occur alongside bradycardia. This article explains the pathophysiology of autonomic dysreflexia, alongside its causes, signs and symptoms. It also details the pharmacological and non-pharmacological management interventions that should be promptly initiated in patients who present to the emergency department with autonomic dysreflexia, to alleviate their symptoms and prevent further complications. © 2019 RCN Publishing Company Ltd. All rights reserved. Not to be copied, transmitted or recorded in any way, in whole or part, without prior permission of the publishers.