Prevention of experimental motion sickness by scopolamine absorbed through the skin.

A double-blind placebo-controlled study compared the efficacy of the antimotion sickness drug scopolamine when administered by oral or transdermal routes. A secondary purpose was to extend our bioassay involving fixed-dose combinations of the homergic drugs promethazine and ephedrine. After receiving 12 apparently identical drug-placebo treatments, eight normal male students were exposed to a slow rotation room to stressful accelerations generated by their execution of 40 head movements out of the plane of the room's rotation of 1 rpm and at 1-rpm increments until either symptoms were experienced (just short of frank motion sickness) or the 27-rpm ceiling on the test was reached. Efficacy of a drug was defined in terms of the placeborange and categorized as beneficial, inconsequential, or detrimental. The rank order of drugs with beneficial effects was: 1) promethazine 25 mg plus ephedrine 12.5 mg (86%); 2) scopolamine by mouth (75%); 3) scopolamine transdermally (63%); and 4) promethazine 12.5 mg plus ephedrine 25 mg (29%). The only detrimental effect was with scopolamine given orally. It is concluded that the advantages of the transdermal scopolamine, which include minimal side effects and prolonged effectiveness, deserve full exploitation.

RCT Entities:   Population Interventions Outcomes