1. A system, comprising: a posture change detector configured to detect posture transitions including a posture change determined to be indicative of an increased risk of syncope; and a neural stimulator configured to deliver a scheduled neural stimulation therapy, the neural stimulator including a syncope avoidance module configured to temporarily override the scheduled neural stimulation therapy to ameliorate the risk of increased syncope only in response to detecting the posture change that is determined to be indicative of the increased risk of syncope, and then return to the scheduled neural stimulation therapy after the risk of syncope from the detected posture change has subsided.