The effect of an Rx-to-OTC switch on medication prescribing patterns and utilization of physician services: the case of vaginal antifungal products.

  • 1 December 1995
    • journal article
    • Vol. 30  (5) , 672-85
Abstract
We examined the impact of over-the-counter (OTC) availability of vaginal antifungal products, beginning in January 1991, on medication prescribing patterns and utilization of physician services. Data on utilization of health care services and prescription medications by female members (ages 11 and older) of the Fallon Community Health Plan (FCHP), a group model health maintenance organization and a component of the Fallon Health Care System of central Massachusetts. The census for such individuals increased from 49,551 in January 1990 to 67,365 in December 1992. Time-series analyses were employed to assess changes in prescribing patterns of vaginal antifungal products and physician visits for vaginitis from January 1, 1990 through December 31, 1992. Monthly numbers of prescriptions for vaginal antifungal products and physician visits per 100 members were measured. Monetary savings relating to the prescription-to-OTC switch were also estimated. The computerized management information system of FCHP contains records on utilization of all health care services and prescriptions filled, collected as part of routine fiscal activities. We identified all vaginally administered products on the FCHP formulary used for the treatment of vaginal candidiasis 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 616.10 ("vaginitis and vulvovaginitis, unspecified") occurring during each month of the study period. For the one-year period after OTC availability of vaginal antifungal products (January 1991 through December 1991), we estimated that the number of prescriptions dispensed for these products was reduced by 6.42 per 100 female FCHP members ages 11 and older. Physician visits for vaginitis were reduced by 0.66 per 100 members. Estimated savings to the Fallon Health Care System for the one-year period following OTC availability were $42,528 in medication costs and $12,768 to $25,729 for costs associated with physician visits, depending on use of laboratory testing in patient evaluations. The findings of this study suggest that the prescription-to-OTC switch of vaginal antifungal treatments reduced health care costs to the insurer in the managed care setting. These favorable effects on costs for the insurer need to be weighed against shifts in medication costs to consumers and potential adverse consequences to the patient relating to errors in self-diagnosis.