The term “comorbidity” describes two or more disorders or illnesses occurring in the same person. They can occur at the same time or one after the other. Comorbidity also implies interactions between the illnesses that can worsen the course of both. Learn more
Published December 2008. Revised September 2010. Introduces a report that focuses on the topic of comorbid drug use disorders and other mental illnesses, a research priority for NIDA.