The Effects of Dextromethorphan on Driving Performance and the Standardized Field Sobriety Test

Dextromethorphan (DXM) is abused most commonly among adolescents as a recreational drug to generate a dissociative experience. The objective of the study was to assess driving with and without DXM ingestion. The effects of one‐time maximum daily doses of DXM 120 mg versus a guaifenesin 400 mg dose were compared among 40 healthy subjects using a crossover design. Subjects’ ability to drive was assessed by their performance in a driving simulator (STISIM^® Drive driving simulator software) and by conducting a standardized field sobriety test (SFST) administered 1‐h postdrug administration. The one‐time dose of DXM 120 mg did not demonstrate driving impairment on the STISIM^® Drive driving simulator or increase SFST failures compared to guaifenesin 400 mg. Doses greater than the currently recommended maximum daily dose of 120 mg are necessary to perturb driving behavior.