When is an overdose more than just an “overdose?”

Alarm about overdose deaths curiously leave out complicating details. Are overdoses the result of fatal levels of a drug? Are they the combined effect of more than one substance? What about drug combinations with substances not classified as drugs? What about adulterated drugs?

Most Overdose Deaths Now Involve Multiple Substances, Rob Siebers, Pew (2025)

Maybe it’s not so recent

Opioid Polysubstance Overdose Deaths in Texas: 2010-2019, Texas Department of State Health Services (DSHS)

Maybe its not so much just “drugs”

America’s Most Common Drug Problem? Unhealthy Alcohol Use, Pew (2024)

Alcohol is the leading driver of substance use-related fatalities in America: Each year, frequent or excessive drinking causes approximately 178,000 deaths.

Prevalence and Characteristics of Alcohol Use in Substance-Involved Deaths in St. Louis, Missouri, From 2011 to 2022,

Melissa Nance, Julia Richardson, Khrystyna Stetsiv, Devin Banks, and Maria Paschke , Journal of Studies on Alcohol and Drugs (2025)

Alcohol or Benzodiazepine Co-involvement With Opioid Overdose Deaths in the United States, 1999-2017, Marco E. Tori, Marc R. Larochelle, and Timothy S. Naimi, JAMA Network Open (2020)

Maybe drugs are adulterated

What is fentanyl and why is it behind the deadly surge in US drug overdoses?, Kavita Babu, UMass Chan Medical School (2022)

The Latest Evolution of the Opioid Crisis: Changing Patterns in Fentanyl Adulteration of Heroin, Cocaine, and Methamphetamine and Associated Overdose Risk,

Jon E. Zibbell, RTI International (2019)