Autonomic hyperreflexia or autonomic dysreflexia is a syndrome seen in approximately 85% of all quadriplegic patients and constitutes the only medical emergency related to spinal cord injury. We report on a paraplegic patient with a C5 to C7 spinal cord injury who suffered autonomic hyperreflexia during percutaneous nephrolithotomy for a right renal stone. The reflex-induced hypertension subsided with termination of the operation, and administration of an alpha and beta-adrenergic blocking agent (labelatol hydrochloride). The stone was removed successfully by pyelolithotomy with the patient under general anesthesia 4 days later.