Background: The present study investigated whether prochlorperazine affects
vestibular-ocular reflex (VOR) and vestibulo-perceptual function. Methods: We
studied 12 healthy naïve subjects 3 hours after a single dose of oral prochlorperazine
5mg in a randomised, placebo-controlled, double-blind, cross-over study in healthy
young subjects. Two rotational tests in yaw were used: 1) a Threshold task
investigating perceptual motion detection and nystagmic thresholds (acceleration
steps of 0.5deg/s/s) and 2) Suprathreshold responses to velocity steps of 90deg/s in
which vestibulo-ocular (VO) and vestibulo-perceptual (VP) time constants of decay,
as well as VOR gain, were measured. Results: Prochlorperazine had no effect upon
any measure of nystagmic or perceptual vestibular function compared to placebo. This
lack of effects on vestibular-mediated motion perception suggests that the drug is
likely to act more as an antiemetic than as an anti-vertiginous agent