Autonomic Dysreflexia (AD), also known as Hyperreflexia, is a potentially dangerous complication of spinal cord injury (SCI).

In AD, an individual's blood pressure may rise to dangerous levels and if not treated can lead to stroke and possibly death. Individuals with SCI at the T-6 level or above are at greater risk.

AD usually occurs because of a noxious (irritating) stimulus below the level of the injury. Symptoms include headache, facial flush, perspiration, and a stuffy nose.