Despite growing concomitant use of opioids and methamphetamines and other stimulants, documentation of this polysubstance use in the electronic health record (EHR) is not fully understood. International Classification of Disease (ICD) codes, a common tool for identifying patient cohorts, are likely to under-detect methamphetamine and other stimulant use. Assessing other forms of documentation in the EHR may inform more sensitive methods of detecting this form of methamphetamine and stimulant use.