Use of herbal therapies by adults seen in an ambulatory care research setting: An exploratory survey

Objective: To identify and characterize patterns of use of herbal products among patients participating in selected research clinics. Design: Survey of three National Institutes of Health (NIH) ambulatory care research clinics. Subjects: Convenience sample of 490 adult patients (168 male, 322 female) a ttending rheumatology, liver, and endocrinology/metabolic research clinics. Results: Of the patients surveyed, 16.7%: (n = 82) reported using herbs. Th ere were no significant sociodemographic differences between herb and nonhe rb users. Indications for herb use differed among the disease groups; patie nts in the endocrine and rheumatology clinics were taking herbs predominant ly for "energy" or "wellness"; those attending the liver clinic tended to u se herbal therapies as treatment for their disease. Mean and median monthly expenditure for herbal products was $30 and $10, respectively. There was a significant positive correlation between number of herbs used and use of o ther dietary supplements (p < 0.0001). Conclusions: One in six patients in ambulatory clinical research settings m ay be taking herbal products in addition to prescribed treatment. This figu re is lower than in the general population, possibly because the patients m ay stop using herbs when participating in a research project. Although empi rical evidence on the beneficial or adverse effects of herb therapy alone o r in combination with drug therapies is limited, clinical researchers shoul d be aware of the potential for confounding clinical trial results.