Objective: It has been suggested that driving a car is relatively safe when the driver is treated with nonsteroid anti-inflammatory drugs than when he or she is treated with opioid analgesics. However, the evidence for this statement is scarce. The objective of this study was to determine the effects of a nonsteroid anti-inflammatory drug (bromfenac 25 mg and 50 mg) and an opioid (oxycodone/paracetamol 5/325 mg and 10/650 mg), and placebo on driving ability, memory functioning, psychomotor performance, pupil size, and mood.
Methods: Out of 30 healthy volunteers, 18 completed this randomized, double-blind, placebo-controlled crossover study, before the study had to be stopped due to bromfenac being pulled out from the market. One hour after administration of the drugs, the participants performed a standardized driving test during normal traffic. Thereafter, driving quality, mental effort and mental activation during driving were assessed. A laboratory test battery was performed 2.5 hours after administration of the drug. Visual analog scales assessing mood and pupil measurements were performed on several occasions during each test day.
Results: Both analgesics did not significantly affect performance in any test. However, volunteers reported that significantly more effort was needed to perform the driving test when treated with oxycodone/paracetamol, and that they experienced increased sedation and reduced alertness. Also, the pupil size was significantly decreased. In contrast, subjective assessments after both doses of bromfenac matched that of placebo.
Discussion: No significant impairment in behavior was found in the volunteers for both bromfenac and oxycodone/paracetamol. The lack of impairment from oxycodone/paracetamol may have been related to the participants reporting increased effort during driving while under the influence of this drug.