Arterial blood pressure, pulse rate and rate pressure product changes following tracheal intubation were studied in 50 patients undergoing elective surgical procedures who received a thiopental-succinylcholine anesthetic intubation sequence. Three treatment groups and a control group were observed. Intravenous labetalol doses of 0.25 mg/kg, 0.5 mg/kg and 1.0 mg/kg, injected prior to anesthesia, were compared with respect to their effect on the cardiovascular sequences to direct laryngoscopy followed by the passage of an endotraeheal tube. The increases in heart rate and rate-pressure product associated with tracheal intubation were significantly prevented in labetalol treated patients, significantly. The increase in arterial pressure was prevented, insignificantly. However, it was dose-dependent. From the above result, a pre-induction dose of labetalol was effective in attenuating the pressure response to laryngoscopy and intubation.