The purpose of the present study was to investigate the effects on driving ability of the new analgesic ethyl-N-(2-amino-6-(4-fluor-phenylmethylamino) pyridin-3-yl) carbamate (flupirtine, D 9998) in comparison with pentazocine and placebo. Flupirtine was tested in a double blind cross-over experiment in 12 healthy volunteers using 7 different tests which are known to correspond to the most important aspects of driving ability. Subjects were given 3 consecutive doses of flupirtine of 100 mg each and tested following the first and third administration. The comparison drug pentazocine and placebo were administered in the same dosage regimen (a single dose of pentazocine amounting to 50 mg). Significant differences between flupirtine and placebo could not be detected. Following single dosage of pentazocine subjects more often reported a general feeling of discomfort, including nausea, dizziness and motion sickness, than was the case after administration of flupirtine. While single administration of pentazocine did not produce any significant differences from placebo, multiple administration resulted in both objective and subjective fatigue symptoms. It was concluded that flupirtine, in contrast to pentazocine, did not produce any impairment in driving ability in healthy volunteers.