CONTEXT: The belief that expanding the role of pharmacists in patient care could improve the safety and efficacy of drug therapy is growing. Specifically, pharmaceutical care programs through which pharmacists provide direct and ongoing counseling to patients have been introduced. Whether such programs reduce medication-related problems or health care utilization is unknown. OBJECTIVE: To assess whether a pharmaceutical care program decreases health care utilization, medication use, or charges. DESIGN: Nonrandomized, controlled trial. SETTING: Staff clinic and freestanding contract pharmacies affiliated with a large HMO in greater Minneapolis-St. Paul (6 intervention pharmacies, 143 control pharmacies). STUDY POPULATION: Adult HMO enrollees (n = 921) with heart or lung disease who used one of the selected pharmacies. INTERVENTION: Patients at intervention pharmacies were invited to participate in the pharmaceutical care program. The protocol-based program consisted of scheduled meetings between trained pharmacists and patients to assess drug therapy, plan goals, and intervene through counseling and/or consultation with other health professionals. OUTCOME MEASURES: Change in number of outpatient clinic visits, unique medications dispensed, and total charges over 1 year of follow-up. RESULTS: In an intention-to-treat analysis (after adjustment for gender, age, Charlson Comorbidity Index, disease category, and the baseline value of the utilization measure), the number of unique medications for patients in the pharmaceutical care group increased more than in the usual care group (1.0 vs. 0.4 unique medications; P = 0.03). There was no difference between the two groups in the change in total number of clinic visits or total costs. In secondary adherence analyses, participants were more likely than the usual care group to increase the number of clinic visits (1.2 vs. -0.9; P = < 0.01) and number of unique medications (1.0 vs. 0.2; P = 0.02). CONCLUSION: Pharmaceutical care for patients with chronic health conditions appears to be associated with a modest increase rather than a decrease in health care utilization.