Scopolamine Treatment and Adaptation to Airsickness.

Airsickness is a clinical syndrome manifesting in a variety of symptoms, particularly nausea and vomiting during flight. Studies of habituation to motion sickness in humans treated by scopolamine have produced conflicting results. The drug accelerated habituation, but a rebound effect on symptom severity was observed after its withdrawal. The purpose of the present study was to investigate whether scopolamine affects the adaptation process. We also evaluated the relationship between initial symptom severity and adaptation to airsickness. Aviator cadets in the first two stages of their training were divided into two groups, treated and not treated by scopolamine. Airsickness severity was evaluated using both simulator sickness and motion sickness questionnaires, and drug administration was recorded. A statistically significant higher rate of adaptation was observed among the scopolamine-treated group compared with the nontreated group. On the simulator sickness questionnaire, rate of adaptation for the two groups was -0.21 ± 0.53 and -0.1 ± 0.17, respectively, and for the motion sickness questionnaire -2.34 ± 1.54 and -0.91 ± 1.41, respectively. Examination of a possible connection between initial symptom severity and adaptation rate failed to reveal a significant relationship. We recommend the use of oral scopolamine to accelerate habituation and find it a relatively safe short-term treatment for airsickness. Our results support the notion that scopolamine accelerates the natural adaptation process.