Evaluation of betahistine for the prevention of seasickness: effect on vestibular function, psychomotor performance and efficacy at sea.

Betahistine was evaluated for the prevention of seasickness in a laboratory and sea study. The effect of 48 mg betahistine on the vestibulo-ocular reflex (VOR) and on psychomotor performance was evaluated in twelve young healthy subjects in a double-blind, placebo controlled, randomized, crossover design. The vestibulo-ocular reflex was evaluated by the Sinusoidal Harmonic Acceleration (SHA) test at frequencies of 0.

Active high-frequency vestibulo-ocular reflex and seasickness susceptibility.

Objectives/hypothesis: The vestibular autorotation test (VAT) examines responses to active head oscillations at frequencies between 2 and 6 Hz in the horizontal and vertical planes while the subject is fixating a visible target. At these frequencies, the vestibulo-ocular reflex (VOR) is the main source of eye movement for ocular stabilization, although other visual and somatosensory information interacts with the response. Because the neural mismatch theory places emphasis on multimodal sensory interactions as the cause of motion sickness, using the VAT, which measures eye movements resulting from vestibular, visual, and, to a certain extent, proprioceptive information and depends on the conscious participation and cooperation of the subject, could be of advantage in evaluating individuals with differing susceptibility to motion sickness.