OBJECTIVES: CareFirst BlueCross BlueShield serves 3.1 million members in Maryland, Washington, D.C., Virginia, and Delaware. The organization provides prescription coverage for 1.1 million members and faces spiraling pharmacy expenditures. There has been considerable debate about insurance coverage of sildenafil citrate, and CareFirst has added this agent to the second tier of the formulary with restriction. There is a quantity limit of six tablets per month (or 18 tablets per three months). However, self-funded accounts have the option of not including this management tool as part of their prescription benefit. This report analyzes the economic impact of sildenafil citrate on a pharmacy's budget. METHODS: All prescription claims data for sildenafil citrate were obtained for the year 2001. The claims file was imported into an Access database for abstraction of required data. RESULTS: There were 65,222 prescription claims for sildenafil citrate in 2001, with each member (N=19,646) averaging 3.3±2.7 prescriptions. CareFirst spent almost $2.6 million on sildenafil citrate, equating to $2.31 per member per year (PMPY), or $0.19 per member per month (PMPM). Thus, sildenafil citrate prescriptions constituted approximately 0.5% of the 2001 pharmacy budget. A total of 1.4% of prescriptions (n=891) were written for 25-mg sildenafil citrate, compared with 48.6% (n=31,717) and 50.0% (n=32,614) for the 50-mg and 100-mg doses, respectively. Ninety-four percent of prescriptions were filled with six tablets, and only 2% of prescriptions (n=1309) exceeded the quantity vs. time limit. Members paid an average copay of $13 per prescription. CONCLUSIONS: This estimate of PMPM cost falls within the range previously reported in the literature. In comparison with PMPM costs reported for other drug classes, such as proton pump inhibitors or cyclooxygenase-2 inhibitors, the amount spent on sildenafil citrate is considerably lower and of lesser concern to the pharmacy budget.