Background: Some of most commonly misused drugs are prescription medications. However, there is little consensus on how to define prescription drug misuse (PDM). The literature contains a wide variety of definitions, with some exclusively including behaviors such as getting high or using another person’s prescription, and others also including any medication use at a dose or frequency higher than prescribed by a doctor. The overarching aim of this study is to quantify the differences between two definitions of PDM on the population estimated prevalence of PDM in the United States (US). The National Study on Drug Use and Health (NSDUH) is an annual survey of the civilian population of the US that assesses substance use and related health variables and is a common source of population estimates of substance use. Before 2015, PDM was defined in the NSDUH as the use of prescription drugs that was not prescribed to the person or only for the experience or feeling they cause. In 2015, this definition was expanded to include a broader range of medication-taking behaviors not prescribed by a doctor, such as using medication in greater amounts, more often, or longer than instructed.
Methods: We utilized data from the 2012 to 2017 NSDUH to quantify annual population estimates of past-year misuse of prescription drugs for each type of drug (opioids, stimulants, tranquilizers and sedatives).
Results: Population prevalence estimates increased from 2014-2015 for all 4 prescription drug types (19.5% increase for opioids, 56.8% increase for stimulants, 17.5% increase for tranquilizers, and 103% increase for sedatives).
Conclusions: Results suggest that the broadening of the PDM definition may have resulted in an increase in the number of people categorized as misusing prescription drugs. There is a need for a cohesive definition of PDM to allow for comparisons over time and across studies.