Although there is increased demand for behavioral health services, there is limited national data on the workforce prescribing psychotropics and/or medications for opioid use disorder (MOUD), and many current estimates are based on self-reported data or clinician rosters. To describe trends in the workforce prescribing psychotropics (i.e., antidepressants, antipsychotics, antianxiety medications, mood stabilizers) and/or MOUD from 2017 to 2021. Cross-sectional analysis of 2017-2021 IQVIA Xponent retail prescription claims data. Clinicians who prescribed more than ten total prescriptions for psychotropics and/or MOUD in a calendar year. We analyzed the number of prescriptions and prescribers by year, month, drug type, specialty type, payor type, and clinician county rurality. There was a 2.7% increase in the number of prescribers between 2017 and 2021, with the highest growth among psychiatric nurse practitioners (44.7%), nurse practitioners (25.5%), and physician assistants (6.5%). Primary care physicians (PCPs) and advanced practice clinicians (APCs) made up more than half of the workforce but prescribed 3.5 times fewer prescriptions on average compared to psychiatric and addiction medicine specialists. PCPs and APCs in rural areas wrote the most prescriptions collectively for psychotropics and MOUD per month. Using prescription data, a proxy for being active in the workforce, goes beyond specialty designation to identify the full workforce prescribing psychotropics and MOUD, including the growing role of APCs and PCPs.