Cough syncope as a cause of motor vehicle crash: fatal distraction?

Coughing is a rare cause of syncope that can contribute to motor vehicle crashes. The precise pathophysiological mechanisms responsible for the syncope are unclear. We report six occasions in which motor vehicle drivers have been involved in serious crashes and cough syncope was cited as the cause. In each occasion, an alternative cause leading to the crash could be identified. Cough as a cause of syncope should be a diagnosis of exclusion and used with great caution as a medico-legal defence. A suggested criterion for confirmation of cough syncope is recommended.