INTRODUCTION: Intravenous sedation is performed to ensure smooth and safe surgery. Dental anxiety is a reaction to an unknown danger. The Spielberger's state-trait anxiety inventory (STAI) can be used to simultaneously evaluate the levels of state and trait anxiety. State anxiety is defined as subjective feelings of nervousness. This study assessed the presurgical anxiety using STAI and performed intravenous sedation for patients whose level of state anxiety was > stage IV. Based on our clinical experience, it is believed that higher doses of sedatives are needed to induce the desired levels of sedation in patients with a high level of state anxiety. OBJECTIVES: This study examined whether the sedative consumption of the patient with a high anxiety level increased. PATIENTS AND METHODS: Patients with state anxiety scores of > or =51 were included in Group V, and those with state anxiety scores ranging from 42 to 50 were placed in Group IV. To induce sedation, intravenous access was established, and a bolus dose of 3.0 mg midazolam was administered intravenously. Sedation was maintained by administering a continuous infusion of propofol, which was aimed at achieving an Observer's Assessment of Alertness/Sedation scale of 10-12/20. In this study, midazolam was initially administered when the body movements appeared to occur or the blood pressure increased. This was followed by the administration of higher doses of propofol if low sedation was observed. RESULTS: There were no significant differences in the patient demographics, duration of sedation, and doses of local anaesthetic agents between Groups IV and V. The midazolam dose and mean propofol dose needed to maintain comparable levels of sedation were significantly higher in Group V than in Group IV. CONCLUSION: In female patients, whose level of preoperative state anxiety is more than Stage V of STAI, a large quantity of sedatives is needed for intravenous sedation.