Pharmacist test-and-treat authority and empirical antibiotic prescribing: Evidence from state Medicaid data.

BACKGROUND: Various states have recently granted pharmacists test-and-treat authority-the ability to prescribe treatment for specified conditions following a positive diagnosis to expand access to healthcare. OBJECTIVES: To estimate the effect of pharmacist respiratory and urinary tract infection (UTI) test-and-treat authority on per capita prescriptions across states. METHODS: The estimated effects of pharmacist respiratory and UTI test-and-treat authority were assessed on aggregate state-level prescriptions for antimicrobials often utilized for empiric treatment of respiratory illnesses (amoxicillin, azithromycin, and oseltamivir) and UTI (sulfamethoxazole/trimethoprim and nitrofurantoin). We report average treatment effect on the treated (ATT), significance, and 95% confidence intervals (CI). RESULTS: The effect of respiratory test-and-treat authority was significant and negative on per capita prescription of azithromycin (ATT = -56.2, CI: -95.3 to -17.0) and amoxicillin (ATT = -66.5, CI: -121.1 to -11.8). The estimated effect was negative and insignificant on oseltamivir (ATT=-17.7, CI: -75.4 to 40.1) and positive but just short of significance on penicillin V (ATT=6.1, CI: -2.5 to 14.7) Effects of UTI test-and-treat authority on nitrofurantoin (ATT=-3.5, CI: -11.2 to 4.1) and sulfamethoxazole-trimethoprim (ATT=15.7, CI: -8.3 to 39.7) were of opposite sign and neither was statistically significant. CONCLUSION: Pharmacist respiratory test-and-treat authority does appear to shape aggregate prescribing patterns at the state level by reducing the rates of antibiotics frequently prescribed empirically for respiratory illnesses. We found no evidence that UTI test-and-treat authority changed prescription patterns nor that oseltamivir prescriptions were affected by respiratory test-and-treat authority.