Why do we focus on the exception and not the rule? Examining the prevalence of mono- versus polysubstance use in the general population.

Although mono-use of drugs is common in the United States at the public health level, it is a much less common presentation than polysubstance use (PSU) among individuals of even mild substance use disorder severity. This means that common efforts to study substances in isolation do not focus upon the most common presentation of the phenomenon. We discuss the importance and implications of embracing a PSU framework in the study of substance misuse and substance use disorders.