THE EFFECT OF AN RX-TO-OTC SWITCH ON MEDICATION PRESCRIBING PATTERNS AND UTILIZATION OF PHYSICIAN SERVICES - THE CASE OF VAGINAL ANTIFUNGALPRODUCTS

Objective. We examined the impact of over-the-counter (OTC) availabili ty of vaginal antifungal products, beginning in January 1991, on medic ation prescribing patterns and utilization of physician services. Data Sources and Study Setting. Data on utilization of health care service s and prescription medications by female members (ages 11 and older) o f the Fallen Community Health Plan (FCHP), a group model health mainte nance organization and a component of the Fallen Health Care System of central Massachusetts. The census for such individuals increased from 49,551 in January 1990 to 67,365 in December 1992. Design. Time-serie s analyses were employed to assess changes in prescribing patterns of vaginal antifungal products and physician visits for vaginitis from Ja nuary 1, 1990 through December 31, 1992. Monthly numbers of prescripti ons for vaginal antifungal products and physician visits per 100 membe rs were measured. Monetary savings relating to the prescription-to-OTC switch were also estimated. Data Collection Methods. The computerized management information system of FCHP contains records on utilization of all health care services and prescriptions filled, collected as pa rt of routine fiscal activities. We identified all vaginally administe red products on the FCHP formulary used for the treatment of vaginal c andidiasis and determined the number of prescriptions filled for these agents during each month of the study period. We also identified the number of physician office visits characterized by the ICD-9-CM code 6 16.10 (''vaginitis and vulvovaginitis, unspecified'') occurring during each month of the study period. Principal Findings. For the one-year period after OTC availability of vaginal antifungal products (January 1991 through December 1991), we estimated that the number of prescript ions dispensed for these products was reduced by 6.42 per 100 female F CHP members ages 11 and older. Physician visits for vaginitis were red uced by 0.66 per 100 members. Estimated savings to the Fallen Health C are System for the one-year period following OTC availability were $42 ,528 in medication costs and $12,768 to $25,729 for costs associated w ith physician visits, depending on use of laboratory testing in patien t evaluations. Conclusions. The findings of this study suggest that th e prescription-to-OTC switch of vaginal antifungal treatments reduced health care costs to the insurer in the managed care setting. These fa vorable effects on costs for the insurer need to be weighed against sh ifts in medication costs to consumers and potential adverse consequenc es to the patient relating to errors in self-diagnosis.