The effects of acute treatment with tandospirone, diazepam, and placebo on driving performance and cognitive function in healthy volunteers.

ABSTRACT

OBJECTIVE: To assess the effects of two anxiolytics, diazepam and tandospirone, on driving performance from methodological viewpoints taking frequent rear-end collisions into account. METHODS: In this double-blinded, three-way crossover trial, 18 healthy males received acute doses of 20 mg tandospirone (TSP), 5 mg diazepam (DZP), and placebo (PCB). The subjects were administered three driving tasks-road tracking, car following, and harsh braking-performed using a driving simulator and three cognitive tasks-Wisconsin Card Sorting Test, Continuous Performance Test, and N-back test-at baseline and at 1 and 4 h post-dosing. The Stanford Sleepiness Scale scores were also assessed. RESULTS: DZP nonsignificantly increased the percent change of brake reaction time (BRT) as compared to PCB at 4 h post-dosing. TSP nonsignificantly decreased the percent change of BRT as compared to PCB. Consequently, there was a significant difference in the percent change of BRT between DZP and TSP at 4 h post-dosing. For the remaining tasks, no statistically significant effects of treatment were observed. CONCLUSIONS: Acute doses of DZP significantly impaired the harsh-braking performance as compared to acute doses of TSP. These findings suggest that TSP may be used more safely in patients' driving activities.