To describe Texas Prescription Monitoring Program (PMP) use and identify predictors of PMP query for opioid and benzodiazepine prescriptions by prescribers and pharmacists. Dispensation and query records from the Texas PMP for opioid and benzodiazepine medications dispensed between October 1, 2016 and December 31, 2018 were linked using common patient identifiers. Autoregressive linear regression was used to assess trends in utilization. Hierarchical logistic models were specified to identify factors associated with provider and pharmacist query of opioid and benzodiazepine prescriptions. Despite a significant increase in the total number of pharmacists (β = 169.85, p < 0.0001) and prescribers (β = 301.59, p < 0.0001) who used the PMP every month, the ratio of active to registered pharmacists (β = -0.0001, p = 0.75) and prescribers (β = -0.0015, p = 0.10) did not change. Pharmacists and prescribers were significantly more likely to query opioid and benzodiazepine prescriptions of 14 days or more, and those issued to patients new to their practice. Pharmacists were most likely to query opioid prescriptions for oxycodone (aOR = 4.51, 95%CI = 4.42-4.60) and prescribers were most likely to query prescriptions for buprenorphine (aOR = 2.24, 95%CI = 2.15-2.35) compared to codeine. Changes in PMP utilization between October 2016 and December 2018 were driven by increasing registration, not increasing frequency of use among registered users. Use of the PMP is inconsistent and dependent upon patient characteristics thus limiting the utility of the PMP as a decision support tool. These results support the need for policy mandating PMP use in Texas and provide a useful baseline and framework to evaluate the effectiveness of mandate implementation.