BACKGROUND: Transient cardiovascular responses are frequently associated with direct laryngoscopy and tracheal intubation. The aim of this study was to investigate the change of hemodynamic response in laryngoscopy and intubation after injection of diltiazem and lidocaine. METHODS: We studied eighty adult patients (ASA 1-3). After intravenous injection of thiopental sodium, each patient received saline (Control), 1 mg/kg lidocaine (Group L), 0.3 mg/kg diltiazem (Group D), or 0.3 mg/kg diltiazem + 1 mg/kg lidocaine (Group DL) 90 seconds before a laryngoscopy. Heart rate and arterial blood pressure were obtained at baseline, just before the laryngoscopy, immediately after intubation, 1, 2, 3 and 4 minutes after intubation. RESULTS: There were no significant differences in the changes of heart rate among all groups. Patients who received saline and lidocaine showed a significant increase in mean arterial pressure associated with tracheal intubation, and these responses were attenuated in diltiazem and diltiazem + lidocaine treated patients. However, there was no significant difference between the diltiazem group and diltiazem + lidocaine group. CONCLUSIONS: This data suggests that 0.3 mg/kg diltiazem or 0.3 mg/kg diltiazem + 1 mg/kg lidocaine treatment are effective methods to attenuate the hypertensive response to laryngoscopy and tracheal intubation. However, injection of diltiazem + a low dose of lidocaine was not more effective than the diltiazem alone group.