Drug-Supplement Combos Safe?

PITTSBURGH--The majority of potential interactions between drugs and supplements such as vitamins and minerals, garlic, Ginkgo biloba, saw palmetto and ginseng have insignificant adverse effects, according to a study published in the Archives of Internal Medicine (164, 6:630-6, 2004) ( archinte.ama-assn.org). However, researchers from the University of Pittsburgh School of Pharmacy warn research supporting this finding is sparse, and health care providers should continue to inquire about supplement use and consider the potential for interactions, regardless of their severity.

Approximately 450 outpatients who were taking prescription medications were involved in the survey. Supplement use was self-reported and cross-referenced with each subjects prescription medication list; medical literature searches and tertiary sources were used to identify potential interactions. Forty-three percent of the subjects were taking at least one dietary supplement, with the most common being vitamins and minerals, garlic, gingko, saw palmetto and ginseng. And of these, 45 percent of the subjects had the potential for a drug-dietary supplement interaction of any significance--the majority (94 percent) were not serious, based on the limited available evidence, according to researchers.