Importance: Prescription Drug Monitoring Programs (PDMPs) can contribute to safer prescribing of opioids and other controlled substances but are often underutilized by prescribers. Evidence on the feasibility and effects of email campaigns to increase clinicians' engagement with PDMP is limited.
Objective: To investigate whether email communications can increase PDMP use and, in turn, reduce guideline-discordant prescribing among clinicians.
Design, setting, and participants: This randomized clinical trial included clinicians who prescribed controlled substances but lacked PDMP accounts, had inactive PDMP accounts, did not search the PDMP, or searched infrequently when prescribing opioids. The study was conducted from January 2024 to November 2025 in the US state of Minnesota.
Interventions: Clinicians were randomized (1:1:1 ratio) to 2 intervention groups or a usual care group. Clinicians in the intervention groups were sent up to 2 emails highlighting their lack of PDMP engagement (no account, inactive account, no search, or infrequent search) with hyperlinks to the PDMP website to rectify it. Email content differed by group to focus on either the state's legal requirements to use the PDMP or the clinical benefits of PDMP use.
Main outcomes and measures: PDMP engagement, defined as engaging in the activity encouraged in the email (account creation, account reactivation, database searches, or more frequent database searching); and guideline-discordant opioid prescribing, a composite of 5 prescribing measures, both measured within 60 days of the initial email. Secondary outcomes included email communication engagement and components of both primary end points.
Results: Among 7872 clinicians, 6574 were physicians (83.5%) and 4385 were men (55.7%). PDMP engagement was 11.8% (309 clinicians) in the usual care group. Legal requirement emails raised the engagement rate by 26.5 (95% CI, 24.3-28.7; P < .001) percentage points, while clinical benefit emails raised engagement 14.2 (95% CI, 12.0-16.3; P < .001) percentage points. Both types of emails raised account holding, database searches, and searches for patients with a history of risky prescribing. Effects endured for at least 7 months. Guideline-discordant prescribing did not differ significantly across groups.
Conclusions and relevance: In this randomized clinical trial, email communications increased PDMP engagement, particularly emails emphasizing legal requirements for PDMP use. Such a low-cost, scalable email intervention may be of interest to policymakers and health care organizations seeking to promote PDMP use. Although these emails did not trigger large-scale changes in prescribing, similar interventions may be useful for promoting other best practices.
Trial registration: ClinicalTrials.gov Identifier: NCT06443385.