INTERACTIONS
(drug/supplement/herb)

"And the wages of ignorance can be death." Canterbury Tales

Along with the increased use of herbals as medicinals and other dietary supplements to improve overall nutritional status, there has been a concomitant increase in the number of interactions of these substances with prescribed and over-the-counter drugs. There is limited understanding of these natural medicinal verses pharmaceutical interaction potentials.

The factors are many that play into these phenomena and the lack of understanding that surround them. One is general uncertainty about active constituents and mechanisms of action of these substances as there is a lack of clinical trials and pharmacological data. Another confounding factor is the inconsistency of dietary supplement products and the high rate of contamination of herbal products in particular. It is inadequately investigated case reports that make up most of the currently available literature on the subject of interactions between drugs, supplements and herbs. This is further complicated by the fact that many people are reluctant to disclose their use of dietary supplements. Unfortunately, use of these substances and the possibility of interactions frequently comes to light with the occurrence of a serious adverse event.

Bibliography/Resources for the Interaction Table

Ezbianski, A. A., Warfarin and Herbal Supplements. Advance for Nurse Practitioners, November 2003:77-80.

Gruenwald, J., Brendler, T., Jaenicke, C., et.al., PDR for Herbal Medicines, Third Edition. Thomson PDR, Montvale, NJ:2004.

Hardy, M. L., Herb-Drug Interactions: An Evidence-Based Table. Alternative Medicine Alert, June 2000:64-9.

Scott, G., Elmer, G., Update on natural product-drug interactions. American Journal of Health-System Pharmacy. 2002;59:339-345.