OBJECTIVE: To assess actions of community pharmacists in response to their patients' concurrent use of prescription medications and complementary and alternative medicine (CAM). DESIGN: Nonexperimental, cross-sectional mail survey. SETTING: Texas. PARTICIPANTS: 107 community pharmacists. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Pharmacists' self-reported rate of patient inquiry about CAM use and actions taken in response to CAM use. RESULTS: A majority (71.0%) of pharmacists had encountered patients who were using CAM, which was defined broadly in the survey to include herbal products, vitamins and minerals, homeopathic products, massage, meditation, and other types of CAM. Pharmacists documented CAM use by patients in 11.0% of cases and reported monitoring for drug-related problems in 38.4% of users. Among CAM users, pharmacists most often encouraged CAM use if medically appropriate. Pharmacists were not comfortable with responding to CAM inquiries but believed they needed adequate knowledge about CAM. In general, pharmacists rarely asked patients about their CAM use. Pharmacists' rate of inquiry about CAM use increased significantly when this information could be documented in patient profiles and when pharmacists had additional training in CAM. Also, in pharmacies that stocked herbal or homeopathic products, pharmacists were significantly more likely to encourage the use of CAM when medically appropriate and to recommend other CAM therapies appropriate for patients' conditions. When no references were available to research CAM, pharmacists tended to neither encourage nor discourage CAM use based on lack of scientific evidence of their effectiveness. CONCLUSION: Most community pharmacists had patients who used CAM, but they were not proactive in inquiring about or documenting this use. They most often encouraged CAM use if deemed medically appropriate. Pharmacists' actions differed on the basis of professional and practice setting characteristics. To ensure optimal drug therapy outcomes, pharmacists should be more proactive in identifying and documenting CAM use by patients.