Volunteer subjects were randomly assigned to two groups administered either a placebo followed by ethanol or ibuprofen followed by ethanol. Subjects served as their own control. Blood ethanol concentration were monitored every 30 to 60 min for up to 4 h with Intoximeter 3000 instruments. A blood sample was drawn at the final Intoximeter test and analyzed for ethanol and ibuprofen by gas chromatography and mass spectrometry, respectively. The mean elimination rate as calculated using Widmark's elimination factors was 0.018 + or - 0.006 g/dl for ethanol and 0.017 + or - g/dl/h for ethanol with ibuprofen. Mean ethanol concentration (g/dL + or - SD) were: 0.095 + or - 0.026 (ethanol) and 0.095 + or - 0.033 (ethanol and ibuprofen at 30 min; 0.077 + or - 0.026 (ethanol) and 0.075 + or - 0.031 (ethanol and ibuprofen) at 150 min; and 0.089 + or - 0.025 (ethanol) and 0.87 + or - 0.030 (ethanol) and ibuprofen) overall. There was no statistically significant effect of ibuprofen on either the peak blood ethanol concentration or the ethanol elimination rate. These results reveal no evidence of a significant ethanol-ibuprofen interaction. (Author abstract)