The Matson Evaluation of Drug Side Effects (MEDS) is currently the best established and most researched measure of drug side effects in the intellectual disability (ID) literature. Initial research was conducted on its psychometric properties such as reliability and validity. More recent research studies have used the measure to determine the interactive effects of severity of drug side effects on adaptive and social behaviors as well as symptoms of commonly medicated psychiatric conditions among persons with ID. Most recently the MEDS has been used to study potential risk factors of psychotropic drugs. The present study was written to review the current status of MEDS research in the broader context of psychotropic drug side effect research in general.