Efficacy of transdermal scopolamine against seasickness: a 3-day study at sea.

Transdermal scopolamine has been reported to provide protection against motion sickness, both while sailing at sea (7-8 h) and under experimental conditions. In this study, we tested the efficacy of transdermal scopolamine and evaluated its side effects during a 72-h cruise at sea. We tested 38 male volunteers, 20-25 years old, who were located on a 3000-ton vessel. The presence of seasickness, defined by Graybiel's diagnostic criteria, was used to calculate percent protection. When sickness was considered as malaise II or more, the drug provided 74, 73, and 39% protection during the three sailing days, respectively. There were no significant differences in the magnitude of the side effects reported by experimental and placebo groups. We conclude that transdermal scopolamine's efficacy against seasickness during a 3-day cruise was not associated with significant side effects and, therefore, we find the drug suitable for long-term use by sailing crews.