Adequate Information to Patients on Lorazepam and Its Expected Actions Enhances the Antianxiety Effect of This Drug During Dental Treatment

Background: Antianxiety agents can be used to pretreat dental outpatients with anxiety or fear of painful dental procedures. No studies, however, have focused on the effects of providing adequate predose information on a drug and its expected actions in reducing dental anxiety.Methods: One-hundred and four dental outpatients aged 20-65 years were randomly assigned to four groups in a double-blinded comparison study to evaluate the antianxiety effects of lorazepam. Groups were given either the drug or a placebo, and were provided either detailed information about the drug and its actions or minimal information prior to dosing. The four groups were as follows: 1) well informed and treated with 0.5 mg of lorazepam; 2) minimally informed and treated with 0.5 mg of lorazepam; 3) well informed and treated with placebo and 4) minimally informed and treated with the placebo. Anxiety levels in patients were scored at baseline and at 35 min and 1 hr after dosing according to the following scales: state anxiety scale of state-trait anxiety inventory (STAI-S), visual analog scale (VAS), and face scale (FS). At the same timepoints, heart rate (HR) was determined as an additional parameter for evaluating anxiety level.Results: Comparison between the lorazepam groups revealed significantly lower anxiety levels in the well informed patients than in the minimally informed patients, as evidenced by significantly decreased STAI-S, VAS, and FS scores at 35 min. The antianxiety effect of lorazepam was more prominent in the well informed group than in the minimally informed group, as evaluated by STAI-S and VAS scores at 1 hr after dosing. Similarly, comparison between the placebo groups showed significantly lower anxiety levels in the well informed patients than in the minimally informed patients, as evidenced by significantly decreased STAI-S and VAS scores at 35 min after dosing. In the placebo groups, HR was significantly lower at 35 min and 1 hr after dosing in the well informed patients than in the minimally informed patients.Conclusion: In the treatment of dental anxiety with lorazepam, providing predose information on the drug and its expected actions to patients enhances the anxiety reducing effects of the drug in dental outpatients.