Driving Impairment Cases Involving Flualprazolam.

Flualprazolam is a novel psychoactive substance in the benzodiazepine class that is increasing in prevalence in the USA. This study describes 19 cases of drivers stopped for impaired driving where flualprazolam was detected. This represents ∼9% of the total cases submitted to the Sedgwick County Regional Forensic Science Center toxicology laboratory between July 2019 and May 2020. Blood concentrations of flualprazolam ranged from 4 to 69 ng/mL, with mean and median concentrations of 20.9 ng/mL and 15 ng/mL, respectively. The increased prevalence in which laboratories are detecting flualprazolam along with the low concentrations necessary for pharmacological effects illustrates the importance of laboratories to remain vigilant in testing for novel psychoactive substances.

Driving Impairment Cases Involving Etizolam and Flubromazolam.

This study describes 12 cases of drivers stopped for impaired driving, where a designer benzodiazepine was detected, specifically etizolam or flubromazolam. Etizolam was detected in three cases, with blood concentrations ranging from 40 to 330 ng/mL. Two of these cases had low concentrations of methamphetamine and/or amphetamine, and in the third case tetrahydrocannabinol (THC) was detected. Flubromazolam was detected in nine cases; in all cases, at least one other drug was detected, with THC being the most prevalent. The mean blood concentration of flubromazolam was 16.3 ng/mL and had a median concentration of 17.0 ng/mL, ranging from 7.0 to 31 ng/mL. The low concentrations of designer benzodiazepines that produce pharmacological effects may allow many of these drugs to go undetected using routine testing in laboratories; therefore, it is necessary to include these novel compounds within validated analytical methods to reduce the chance of reporting false negative results. The prevalence in which laboratories are detecting the presence of novel benzodiazepines in impaired drivers illustrates the increased threat to public safety. These case studies demonstrate the importance of investigating agencies and forensic laboratories to be vigilant in monitoring the emerging novel psychoactive substances in their region.

Fentanyl and Driving Impairment.

The incidence of fentanyl in forensic toxicology analyses in the USA has dramatically increased over the past several years. The increase in death cases has been well studied; however, little has been reported on the impact to drug impaired driving. Fentanyl driving while under the influence of drugs (DUID) case data from 2014 to 2019 is presented. The data were obtained from three toxicology laboratories in the Northeast, Southeast, and Midwest regions of the USA. Fentanyl whole blood concentrations ranged from 0.1 to 157 ng/mL in living drivers with a 466% to 524% increase in fentanyl-positive DUID cases from 2014 to 2019, depending on the US region. The vast majority of fentanyl cases involved poly-drug use. Twenty case histories are presented where fentanyl was the only drug identified. The mean (standard deviation) fentanyl concentration for these cases was 5.2 ± 3.8 ng/mL with a median of 3.7 ng/mL, and the concentrations ranged from 2.0 to 16 ng/mL. Naloxone administration was documented in exactly half of these cases similar to another study involving carfentanil-impaired driving. The case histories also demonstrate that some recreational opioid users may display limited signs of impairment either due to tolerance or naloxone administration. The top three observations in common among the cases were the driver was found unresponsive behind the wheel, the vehicle left the travel lane or roadway, and the driver was involved in a crash. The increase in fentanyl use not only poses a risk for overdose and death, but is also a significant concern for traffic safety. This study supports the movement of fentanyl from a Tier II drug to Tier I due to its significant potential for impairment and increase in prevalence in impaired driving cases.