To date, opipramol has not been examined within the context of evening premedication in anaesthesiology. A suitable drug for such an application should induce anxiolytic and sleep-favouring effects. Due to its pharmacological properties, one would expect opipramol to lead to these effects. In order to test this possibility, 72 female patients were randomly assigned to 50 mg opipramol, 100 mg opipramol, or placebo (n = 24 patients per group) in the evening prior to surgery in a double-blind trial. Effects were recorded in the morning prior to the operation by means of self-rating questionnaires, regarding the patients' current subjective state and their judgement of the quality of sleep during the night before. The self-rating was done by the Multidimensional Mood Inventory BSKE (EWL), by use of the Multidimensional Somatic Symptom List (MSKL), and by use of the Würzburg Sleep Questionnaire. Further dependent variables were heart rate and blood pressure. Opipramol significantly improved sleep quality. Especially the frequency of awakening at night was reduced. These effects could be observed predominantly after 100 mg opipramol. At this dosage, inner excitement was reduced as well. The autonomic variables remained uninfluenced. There were no adverse events and no hints for interactions with anaesthesiology.