Retrograde amnesia after intravenous sedation and general anaesthesia in a dental hospital.

Midazolam, a benzodiazepine, is commonly used for intravenous sedation for dental procedures and, together with other benzodiazepines, can cause anterograde amnesia. Retrograde amnesia, however, is rare. It is defined as a loss of access to memory of events that occurred, or information that was learned, before the injury or event that caused the amnesia. We know of no reports of this occurring after the intravenous use of midazolam alone and few after general anaesthesia. We present two cases of retrograde amnesia: one after intravenous sedation and one after general anaesthesia.