BACKGROUND: Tracheal intubation is accompanied by varing degrees of sympathetic stimulation as reflected by increases in heart rate, and blood pressure and several clinical trials to reduce the effects on blood pressure and heart rate by pharmacologic agents such as and blockers, calcicum channel blockers, narcotics and lidocaine, have been reported. METHODS: To evaluate the effect of fentanyl, lidocaine, esmolol on the hemodynamic changes induced by intubation, we administered thiopental 5 mg/kg only (group 1, n=12), fentanyl 2 g/kg with thiopental 5 mg/kg (group 2, n=12), lidocaine 1 mg/kg with thiopental 5 mg/kg group 3, n=12) or esmolol 0.5 mg/kg with thiopental 5 mg/kg (group 4, n=12) for induction of anesthesia, and measured heart rate, systolic blood pressure, diastolic blood pressure, mean arteiral pressure, and rate-pressure products (RPP) before induction, after induction, after intubation and at 1, 2, 3, and 5 minutes after intubation. RESULTS: There was a significant increase in heart rate, systolic blood pressure and RPP after intubation and 1 min after intubation in all groups, but in group 2, group 3 and group 4, the cardiovascular responses were more attenuated compared to group 1. CONCLUSION: The preintubation intravenous injection of fentanyl, lidocaine and esmolol may offer important roles in the hemodynamically unstable patients because it attenuate cardiovascular responses with intubation.