The effect of breathing 0.1 minimum alveolar concentrations (MAC) of desflurane or isoflurane for three minutes on the incidence of adverse airway events on a subsequent breath of 2 MAC was investigated. Twenty-five volunteers known to develop an adverse airway event to desflurane or isoflurane took part in the study. Each volunteer was exposed to isoflurane and desflurane at least 24 h apart. Volunteers were assessed for adverse airway events while breathing 2 MAC inhalational anaesthetic following breathing 100% O(2) for 3 min. This was repeated with 0.1 MAC inhalational anaesthetic in oxygen instead of 100% O(2). Adverse airway events decreased from 88% to 40% when tests were conducted with desflurane (p = 0.002). With isoflurane, the reduction from 60% to 52% was not statistically significant (p = 0.774). Breathing low concentrations of desflurane decreases the incidence of adverse airway events on subsequent inhalation of higher concentration of desflurane.