A 23-year-old healthy man was scheduled for extraction of his mandibular third molars under general anesthesia with nasotracheal intubation. Sudden sinus tachycardia up to 170 beats/min occurred when applying an epinephrine solution-soaked swab into the nasal cavity for preventing epistaxis during intubation. This was presumably evoked by submucosal migration of the swab into a false passage created because of the force applied during a prior failed attempt at nasal passage of the tracheal tube, and rapid epinephrine absorption by the traumatized mucosa. The causes of the unexpected severe tachycardia in our patient are discussed.