Objective: The aim of this study is to evaluate propofol and midazolam as sleep inducers in drug-induced sleep endoscopy, for the topographic diagnosis of upper airway obstruction during sleep; compare one to the other as well as with natural sleep polysomnography results. Method: Prospective series of 16 patients with suspected obstructive sleep apnea. Following physical examination and conventional polysomnography, sleep nasendoscopy along with simultaneous polysomnography was performed, obtaining apnea-hypopnea index, lowest oxygen saturation, apnea durations, and sleep cycle stages. The procedure was done with propofol and with midazolam. Results: There were 15 men and 1 woman; the mean age was 42.7 years old, mean body mass index 26.86. Average drug-induced sleep endoscopy (DISE) duration was 20 minutes with propofol and 14.3 minutes with midazolam. The induced-sleep stage obtained was of phase 2. On 12 of the patients a whole-night polysomnography study was performed and compared with sleep nasendoscopy results. Physical exam did not correlate with drug-induced sleep findings. There was a good correlation between DISE results with both drugs ( P < .001). The average apnea-hypopnea index was 16.38 for natural sleep, 28.63 for propofol, and 38.11 for midazolam. Conclusion: Obstruction areas are equivalent no matter which of the 2 mentioned sedatives are used. Although DISE is not entirely equivalent to an entire night sleep it can be considered comparable to most of the night sleep events.