When gatekeepers meet the sentinel: The impact of a prior authorization requirement for cefuroxime on the prescribing behaviour of community-based physicians

Aims: Prior authorization (PA), the requirement of physicians to obtain pre-approval as a prerequisite for coverage, may decrease drug utilization via a 'sentinel effect', a decrease in utilization caused by external review of prescribing. The purpose of this study was to assess the affect a PA restriction had on the utilization patterns of cefuroxime tablets in a managed care organization (MCO) in Israel. Methods: Physician prescribing patterns were evaluated by conducting a retrospective drug utilization analysis. Data were derived from the electronic patient records of the MCO studied. All prescriptions for solid state antibiotics for patients diagnosed with an infectious disease written during three parallel 3-month segments, before, during and after a PA restriction for cefuroxime was enforced, were included. Frequency and proportion of antibiotic prescriptions for cefuroxime tablets, distribution of infectious diseases treated with cefuroxime, and the request rejection rate when PA was required were calculated. Results: Prescriptions for cefuroxime declined from 5538 prescriptions (8.0% of eligible antibiotic prescriptions, 95% CI 7.8, 8.2) in the initial period to 1036 (1.2%, 95% CI 1.1, 1.3) during the PA period, rising to 3961 (4.3%, 95% CI 4.2, 4.4) in the post-PA period. Changes in the distribution of diseases treated with cefuroxime during the PA stage tended to regress after revocation to those observed in the pre-PA period. The rejection rate was found to be 8.5% (95% CI = 6.9, 10.1). Conclusions: The implementation of a prior authorization requirement for cefuroxime tablets markedly reduced the use of this drug, probably due to a 'sentinel effect'.