Fig. 1.

a Motion-sickness score following pretreatment with rizatriptan vs. motion-sickness score following pretreatment with placebo in response to a complex vestibular stimulus, i.e. off-vertical axis rotation. Scores represent the increase in motion sickness above pre-stimulus baseline. Note that data are shown only from those subjects whose vestibular-induced increase in motion-sickness score exceeded 3 after pretreatment with placebo. Data from subjects with migraine-related dizziness are shown as filled circles. Data from subjects without migraine-related dizziness are shown as open circles. Note that for 13 of 15 subjects that the increase in motion-sickness score above baseline was greater following pretreatment with placebo as compared to that seen following treatment with rizatriptan. b Motion-sickness scores following a second off-vertical axis rotation. Data are shown for those subjects who could complete a second off-vertical axis rotation following pretreatment with rizatriptan and following pretreatment with placebo. Note the lack of an obvious effect of rizatriptan