Fentanyl, Acetylfentanyl and Carfentanil in Impaired Driving Cases: A Review of 270 Cases.

The detection of fentanyl (FEN) and FEN analogs has been widely communicated throughout the scientific community. While most of the reporting has been in relation to overdose deaths, these drugs are commonly detected in impaired driving cases. A retrospective study of impaired driving cases analyzed between 2017 and 2019 produced 270 cases positive for FEN, carfentanil (CFEN) and/or acetylfentanyl (AFEN). FEN was the predominant drug found in these 270 cases (65.5%) with concentrations ranging from less than 1.0 to 64 ng/mL. CFEN was found alone in 6.6% cases with three concentrations above 1.0 ng/mL. AFEN was always found when FEN was positive with concentrations ranging from <1.0 to 9.2 ng/mL. Detailed case histories are provided with corresponding toxicology results. Toxicology results show impaired drivers using multiple drugs with a wide range of observed behaviors. The inclusion of these drugs in routine impaired driver toxicology testing is extremely important when attempting to determine their overall prevalence.