Study: Gabapentin-Related Overdose Deaths Increasing, Associated with Opioid Use

Gabapentin detection and involvement in overdose deaths increased during 2019 and 2020, according to a study published in the CDC’s Morbidity and Mortality Weekly Report. Gabapentin, an anticonvulsant medication and the seventh most commonly prescribed medication in the United States, can be used to potentiate illicit opioids.

“Although gabapentin is generally considered safe and is infrequently associated with overdose on its own, when used with other central nervous system depressants such as opioids, there is risk for respiratory depression, potentially resulting in death,” the authors wrote.

Researchers analyzed data from the State Unintentional Drug Overdose Reporting System (SUDORS) in 23 states and the District of Columbia to assess quarterly trends in gabapentin-involved overdose deaths of unintentional or undetermined intent during 2019 to 2020.

SUDORS requires jurisdictions to abstract data from death certificates and medical examiner or coroner reports, including postmortem toxicology reports. Postmortem toxicology reports identify detected drugs and those involved, meaning those determined to be the cause of death.

Of 62,652 overdose deaths occurring between 2019 and 2020 recorded in SUDORS, 58,362 deaths had documented toxicology results. Among these, 5687 (9.7%) had gabapentin detected on postmortem toxicology.

Gabapentin-involved deaths occurred in 2975 of 5687 decedents (52.3%) with a positive gabapentin test result. Most gabapentin-involved overdose deaths, 83.2%, occurred among non-Hispanic White persons. More than half of gabapentin-involved deaths, 52.2%, occurred among persons aged 35 to 54 years. Gabapentin-involved overdose deaths occurred with nearly equal frequency among men and women.

According to the report, the number of deaths reported with gabapentin detected approximately doubled during the second quarter of 2020 compared with the first quarter of 2019. A total of 801 deaths with gabapentin detected occurred during the fourth quarter of 2020.

Among deaths in which gabapentin was detected, nearly half, 49.4%, were gabapentin-involved during the first quarter of 2019. This percentage increased to 55.1% during the fourth quarter of 2020.

The percentage of opioid-involved deaths with gabapentin detected remained consistently high ranging from 85% to 90%, according to the report.

Illicit opioid-involved deaths accounted for 56.8% of overdose deaths with gabapentin detected in the first quarter of 2019 and 69.2% in the last quarter of 2020. The authors suggest that this increase was largely driven by illicitly manufactured fentanyl and fentanyl analogs.

The percentage of deaths with gabapentin detected that involved a prescription opioid declined from 41.9% in the first quarter of 2019 to 33% during the last quarter of 2020. The percentage of deaths with gabapentin detected that involved a stimulant was low and generally stable, ranging from 6% to 9%.

Nearly 90% of drug overdose deaths in which gabapentin was detected also involved an opioid.

Generally, gabapentin detection and involvement in fatal drug overdoses increased during 2019 to 2020. According to the report, this follows a rising trend in overall overdose deaths during the COVID-19 pandemic. The authors suggest that overall increases were largely driven by increases in synthetic opioids and likely exacerbated by the social and economic consequences of the pandemic.

They note that gabapentin testing is recommended as part of comprehensive postmortem toxicology testing protocols for postmortem toxicology testing protocols for drug overdose death investigations in the United States. However, as gabapentin is not included in the list of substances recommended in an adequate analyte panel and is not uniformly included on death certificates by some certifiers, deaths involving gabapentin or with gabapentin detected are likely underestimated.

They suggest including routine gabapentin testing as a part of comprehensive postmortem toxicology testing protocols for drug overdose death investigations to further elucidate the role of gabapentin in drug overdose deaths.

The finding that gabapentin detection and involvement in overdose deaths increased during 2019 to 2020 suggests the dangers of polysubstance use, particularly co-use of gabapentin and illicit opioids. The authors encourage educating persons who use illicit opioids with gabapentin about the increased risk for respiratory depression and death.

Reference

Mattson CL, Chowdhury F, Gilson TP. Trends in Gabapentin Detection and Involvement in Drug Overdose Deaths—23 States and the District of Columbia, 2019-2020. CDC MMWR. 2022;71(19). https://www.cdc.gov/mmwr/volumes/71/wr/mm7119a3.htm?s_cid=mm7119a3_w#contribAff. Published May 13, 2022. Accessed July 18, 2022.