BACKGROUND: Although community pharmacists have historically been paid primarily for drug distribution and dispensing services, medication therapy management (MTM) services evolved in the 1990s as a means for pharmacists and other providers to assist physicians and patients in managing clinical, service, and cost outcomes of drug therapy. The Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (MMA 2003) and the subsequent implementation of Medicare Part D in January 2006 for the more than 20 million Medicare beneficiaries enrolled in the Part D benefit formalized MTM services for a subset of high-cost patients. Although Medicare Part D has provided a new opportunity for defining the value of pharmacist-provided MTM services in the health care system, few publications exist which quantify changes in the provision of pharmacist-provided MTM services over time.OBJECTIVES: To (a) describe the changes over a 7-year period in the primary types of MTM services provided by community pharmacies that have contracted with drug plan sponsors through an MTM administrative services company, and (b) quantify potential MTM-related cost savings based on pharmacists' self-assessments of the likely effects of their interventions on health care utilization.METHODS: Medication therapy management claims from a multistate MTM administrative services company were analyzed over the 7-year period from January 1, 2000, through December 31, 2006. Data extracted from each MTM claim included patient demographics (e.g., age and gender), the drug and type that triggered the intervention (e.g., drug therapeutic class and therapy type as either acute, intermittent, or chronic), and specific information about the service provided (e.g., Reason, Action, Result, and Estimated Cost Avoidance [ECA]). ECA values are derived from average national health care utilization costs, which are applied to pharmacist self-assessment of the "reasonable and foreseeable" outcome of the intervention. ECA values are updated annually for medical care inflation.RESULTS: From a database of nearly 100,000 MTM claims, a convenience sample of 50 plan sponsors was selected. After exclusion of claims with missing or potentially duplicate data, there were 76,148 claims for 23,798 patients from community pharmacy MTM providers in 47 states. . During the 7-year period, pharmacistprovided MTM interventions changed from primarily education and monitoring for new or changed prescription therapies to prescriber consultations regarding cost-efficacy management (Pearson chi-square P < 0.001). Services also shifted from claims involving acute medications (e.g. penicillin antibiotics, macrolide antibiotics, and narcotic analgesics) to services involving chronic medications (e.g., lipid lowering agents, angiotensin-converting enzyme [ACE] inhibitors, and beta-blockers; P < 0.001), resulting in significant changes in the therapeutic classes associated with MTM claims and an increase in the proportion of older patients served (P < 0.001). These trends resulte...