Purpose. To assess the impact of medication use on improvements in coronary heart disease (CHD) risk among WISEWOMAN participants. Design. Pre-post analysis. Setting. WISEWOMAN projects operating at the local level in 8 states. Subjects. WISEWOMAN participants with baseline and one-year follow-up data with at least one abnormal risk factor at baseline (N = 2385; 24% of women with baseline visits). Intervention. WISEWOMAN provides low-income uninsured women with CHD risk factor screenings, lifestyle interventions, access to medications, and referral services. Measures. One-year changes in blood pressure, cholesterol, and 10-year CHD risk by medication status. Analysis. Regression analysis was used to estimate risk factor changes by medication status (newly medicated women, women medicated at baseline, or not medicated women) and quantify the percentage of improvements in risk factors attributed to medication use. Results. Participants experienced statistically significant improvements in systolic (12.6 mm Hg) and diastolic (9.7 mm Hg) blood pressure, total (25.7 mg/dl) and HDL (4.9 mg/dl) cholesterol, and 10-year CHD risk (11.6%). Medication use was responsible for 4% to 5% of the reduction in blood pressure, 32% of the reduction in total cholesterol, 3% of the increase in HDL cholesterol, and 31% of the reduction in 10-year CHD risk. Conclusions. Some of the improvements in CHD risk factors can be attributed to medication use; however, the majority of improvements are likely driven by a combination of other factors, including screenings, risk factor counseling, and lifestyle interventions.