Gabapentin in drugged driving investigations

The increasing use and misuse of gabapentin pose a major risk to public health and traffic safety. Gabapentin has been approved by the Food and Drug Administration (FDA) since 1993 for adjunctive therapy in the treatment of epilepsy and neuralgia but is increasingly being prescribed for numerous off-label uses including insomnia, anxiety, depression, and migraine. Reported side effects include blurred vision, drowsiness, and loss of coordination. Driving behaviors such as exiting the lane of travel and crashes have been reported in connection to drugged driving investigations concerning gabapentin. To further assist with the toxicological interpretation of gabapentin in driving under the influence of drugs (DUID) scenarios, a review of approximately 108,000 gabapentin-positive DUID cases was conducted. Of those, 858 cases met inclusion criteria and underwent additional evaluation. Blood specimens were screened via enzyme-linked immunosorbent assay (ELISA) and confirmed by liquid chromatography tandem mass spectrometry (LC-MS/MS) for quantitation of gabapentin. This review found an overall DUID gabapentin positivity of 7.9% between January 2020 and December 2022; 17 states from various geographical regions had at least one positive gabapentin DUID case. Observations in six driving and human performance cases where gabapentin was the only drug reported were consistent with the known adverse effects of the medication. Half of the case histories reviewed involved crashes where the driver was determined to be at fault. Additionally, 94% of the cases in this review involved gabapentin in combination with other drugs. The most prevalent drug combinations were opioids and gabapentin present in 64% of cases.