Autonomic dysreflexia, also known as hyperreflexia, means an over-activity of the Autonomic Nervous System causing an abrupt onset of excessively high blood pressure. Persons at risk for this problem generally have injury levels above T-5. Autonomic dysreflexia can develop suddenly and is potentially life threatening and is considered a medical emergency. If not treated promptly and correctly, it may lead to seizures, stroke, and even death.