Introduction: The historical separation between medicine and dentistry has resulted in the creation of separate health records, which have the potential to negatively impact patient care and safety. Of particular importance, errors or omissions in medication lists in separate electronic health records (EHRs) may lead to medical errors and serious adverse outcomes. Objective: This study aimed to compare medication lists reported in the EHRs of active patients treated by both the University of Michigan School of Dentistry and Michigan Medicine to determine if differences exist. Methods: In this cohort study, EHRs of a population of 159,733 patients that the University of Michigan medical and dental clinics share in common were investigated for agreement in the reporting of 16 medications. After exclusion of minors and patients not seen in the last 5 y, records of 27,277 patients were examined. Results: The maximum percentage of agreement in medications reported in both records was 52% for levothyroxine, and the minimum was 7% for sildenafil. The medical record had a significantly higher number of unique medications than the dental record, suggesting higher underreporting in the dental setting. Conclusion: The lack of agreement in the report of medications with serious dental and medical implications argues in favor of unification of records and use of available technology to increase accurate medication reporting. Knowledge Transfer Statement: The results demonstrate a lack of agreement between medications reported in medical and dental records, which can have serious implications to patients’ health. A unified health record, employing available technology to increase accurate medication reporting, would mitigate this problem.