The efficacy and tolerability of Diazemuls versus conventional diazepam as endoscopic premedication was evaluated in a study with a cross-over design performed in 26 patients undergoing upper gastrointestinal tract endoscopy. No statistically significant differences were found between the two forms of premedication with regard to degree of sedation, patient compliance or recovery of psychomotor function. With respect to short-term amnesic effects, efficacy and tolerability Diazemuls was comparable to the conventional formulation of diazepam. Diazemuls may therefore be proposed as an alternative premedication for endoscopy.