Diphenhydramine-involved Fatal and Nonfatal Drug Overdoses in Tennessee, 2019–2022

Abstract

Background

Diphenhydramine (DPH), known as the brand name Benadryl, is an over-the-counter medication associated with accidental ingestion leading to nonfatal overdoses. Additionally, DPH has been used in tandem with illicit substances leading to fatal drug overdoses.

Objective

In response to DPH being seized with illicit drugs as an adulterant, as well as its growing intentional misuse, we sought to explore its recent involvement in fatal and nonfatal drug overdoses in the state of Tennessee.

Methods

We conducted a statewide cross-sectional study to determine the characteristics of DPH-involved fatal and nonfatal overdoses in Tennessee during 2019–2022 using data from the State Unintentional Drug Overdose Reporting System, the Electronic Surveillance System for the Early Notification of Community-based Epidemics, and the National Forensic Laboratory Information System Public Data Query System. Frequencies were generated to compare demographic characteristics, circumstances, and toxicology between fatal and nonfatal DPH-involved overdoses.

Results

We identified 143 suspected nonfatal DPH and 409 fatal DPH-involved overdoses in Tennessee from 2019 to 2022. Nonfatal overdoses remained consistent while fatal overdoses peaked in 2021. Most nonfatal overdoses were under 18 (63.4%), while most fatal overdoses were between 18 and 64 years of age (95.7%). For fatal overdoses, fentanyl was the most prevalent substance on toxicology followed by prescription opioids.

Conclusion

Nonfatal overdoses remained consistent while fatal overdoses peaked in 2021 in Tennessee. Use of DPH among other illicit substances lends to evidence suggesting its use as an adulterant. Monitoring of DPH-involved fatal and nonfatal overdoses is critical to inform harm reduction initiatives.

Keywords:

• Fatal drug overdose
• nonfatal drug overdose
• diphenhydramine
• drug seizure
• surveillance
• Tennessee

Declaration of interest

The authors declare that they have no conflict of interest. The authors alone are responsible for the content and writing of the article.

Data availability statement

The data that support the findings are available upon request from the Tennessee Department of Health.

Table 1. Characteristics of diphenhydramine-involved fatal and nonfatal overdoses in Tennessee, January 1, 2019–December 31, 2022.

Table 2. Circumstances surrounding diphenhydramine-involved fatal drug overdoses in Tennessee, January 1, 2019–June 30, 2022.

Additional information

Funding

This work was supported by a grant from the Centers for Disease Control and Prevention, Overdose Data to Action [5 NU17CE924899].