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Background and Objective: In particular medical situation administration of muscle relaxants following intravenous anesthetics for tracheal intubation may be unnecessary or hazardous. The aim of this study was the comparison of larengoscopy and intubation conditions after induction of anesthesia with propofol or thiopental with remifentanil in the absence of muscle relaxants. Materials and Methods: In a randomized, and double – blind clinical trails, 42 ASA class 1 and 2 patients assigned randomly to propofol 2mg/kg group or thiopental 5mg/kg group. All patients received lidocaine 1.5mg/kg and remifentanil 2.5 µg/kg 30 second before anesthetics administration. Ninety second after administration of the hypnotic agent's, larengoscopy and intubation were attempted. Intubating conditions were assessed as excellent, good, suitable or poor on the basis of mask ventilation, jaw relaxation, vocal cords position and patient's response to intubations and indotracheal tube cuff inflation. The mean arterial pressure and heart rate were measured before and after anesthetic administration, and immidately, 2 and 5 minutes after intubations. Results: 40% of patients in thiopental group and 80% of patients in propofol group showed either excellent or good conditions for larengoscopy and tracheal intubation (P<0.05). Mean arterial pressure and heart rate were decreased more significantly in propofol group in respect to thiopental group (P<0.05). Conclusion: This investigation showed that propofol in combination with remifentanil is better than thiopental for tracheal intubation without muscle relaxants. However, it induces more homodynamic changes.