BackgroundIncreasing access to naloxone reduces opioid-related morbidity and mortality. Primary care and community pharmacy settings are critical access points, yet limited theoretical research has examined naloxone prescribing and dispensing behaviors. ObjectivesTo determine if the theory of planned behavior (TPB) combined with theoretical constructs from communication science explains intentions to co-prescribe and discuss co-dispensing naloxone among primary care physicians and community pharmacists, respectively. MethodsThis cross-sectional study surveyed cohorts of licensed primary care physicians and community pharmacists in Tennessee in 2017. Intentions were measured using profession-specific case vignettes, whereby they were asked given 10 similar patients, how many times (0–10) would they co-prescribe or discuss co-dispensing naloxone. Bivariate and multivariable analyses were used. ResultsThe analytic sample included 295 physicians (response rate = 15.6 %) and 423 pharmacists (response rate = 19.4 %). Approximately 65 % of physicians reported never intending to co-prescribe naloxone (0 out of 10 patients), while 47 % of pharmacists reported never intending to discuss co-dispensing. All TPB constructs—attitudes (AOR = 1.32, CI = 1.16–1.50), subjective norms (AOR = 1.17, CI = 1.06–1.30), and perceived behavioral control (AOR 1.16, CI = 1.02–1.33)—were associated with an increased likelihood of pharmacists always (versus never) discussing co-dispensing. Similarly, two TPB constructs—attitudes (AOR = 1.41, CI = 1.19–1.68) and subjective norms (AOR = 1.22, CI = 1.08–1.39)—were associated with an increased likelihood of physicians always co-prescribing. Among physicians only, one communication construct—self-perceived communication competence (AOR = 1.19, CI = 1.01–1.41)—was associated with an increased likelihood of always co-prescribing. ConclusionFindings support the value of theory, particularly TPB, in explaining primary care physician intentions to co-prescribe and community pharmacist intentions to discuss co-dispensing naloxone.