Drug treatment of motion sickness: scopolamine alone and combined with ephedrine in real and simulated situations.

In two placebo-controlled, double-blind, randomized trials scopolamine (0.3 mg) alone or combined with ephedrine (25 mg) was tested for its effectiveness in the prevention of seasickness during 24 h at sea and of motion sickness in rotating chair tests in a laboratory. Scopolamine was effective both alone and in combination with ephedrine, which supports the hypothesis on central cholinergic overactivity in the pathogenesis of motion sickness. Ephedrine did not markedly increase the effectiveness of scopolamine. Side-effects were slight and did not disturb the operating ability of the volunteers.