CENTRAL ACTION OF CINNARIZINE AND FLUNARIZINE - A SACCADIC EYE-MOVEMENT STUDY

The mechanism of action of flunarizine (FZ) and cinnarizine (CZ) on th e CNS is not fully understood. Computer analysis of saccadic eye movem ents (SEM) provides a sensitive and objective method for evaluating dr ug effect on the function of specific brain structures. This study aim ed to assess the effect of a single oral dose of FZ (20 mg) and CZ (15 0 mg) on CNS function by means of computer analysis of SEM. Ten health y volunteers were studied according to a double-blind, cross-over, pla cebo-controlled design. Peak saccadic velocity (PSV), which is related to the function of a specific group of burst neurons located in the b rain stem, was significantly reduced by FZ. No significant effect of F Z on saccade accuracy (SA) and saccade latency (SL) was found. CZ did not produce significant effects on SEM, but a trend to decrease PSV. T he possibility that a FZ central effect may be related to a stabilizin g action on burst activity of neurons is discussed.