Increased rates of diphenhydramine overdose, abuse, and misuse in the United States, 2005-2016

To describe trends in abuse, misuse, and suicide attempts involving diphenhydramine (DPH).

We analyzed intentional DPH exposures of individuals ≥10 years old reported to U.S. Poison Control Centers using data from the National Poison Data System, 2005-2016.

There were 158,774 intentional DPH exposures in our dataset. The rate of intentional exposures increased 63% over the 12-year study period for all ages combined. Suicide attempts involving DPH showed a bimodal distribution-increasing 263% among children 10-14 years of age, and 126 and 143% among those 55-64 and ≥65 years of age, respectively. Older adults in both the 55-64 and ≥65-year-old age groups had about a 230% increase in rates of misuse. Major adverse clinical effects increased by 91%. There were 745 total reported deaths with a 3.6% increase across all age groups.

Intentional DPH exposures among individuals ≥10 years old have been increasing since 2005. Increasing rates of suicide attempts among children ages 10-14 and increasing misuse among individuals ≥65, coupled with a trend toward greater severity of overdoses, highlight the significant public health impact of this commonly available over-the-counter drug.