Use of herbal products and potential interactions in patients with cardiovascular diseases

Abstract

More than 15 million people in the U.S. consume herbal remedies or high-dose vitamins. The number of visits to providers of complementary and alternative medicine exceeds those to primary care physicians, for annual out-of-pocket costs of $30 billion. Use of herbal products forms the bulk of treatments, particularly by elderly people who also consume multiple prescription medications for comorbid conditions, which increases the risk of adverse herb-drug-disease interactions. Despite the paucity of scientific evidence supporting the safety or efficacy of herbal products, their widespread promotion in the popular media and the unsubstantiated health care claims about their efficacy drive consumer demand. In this review, we highlight commonly used herbs and their interactions with cardiovascular drugs. We also discuss health-related issues of herbal products and suggest ways to improve their safety to better protect the public from untoward effects.

Figure 1

Comparison of Number of Visits, Costs, and Conditions Treated Medically or by Complementary and Alternative Medicine. A, Annual visits to physicians vs those to complementary and alternative medicine (CAM) practitioners; B, the costs of CAM services by type compared with the costs of physician services and hospitalizations; and, C, the most common conditions for which CAM therapies are used in the United States. GI indicates gastrointestinal. (A and B, Adapted from Eisenberg et al [1]. Used with permission.) (C, Data from Barnes PM, Powell-Griner E, McFann K, Nahin RL. Complementary and alternative medicine use among adults: United States, 2002. Advance data from vital and health statistics; no 343. Hyattsville [MD]: National Center for Health Statistics; c2004.)

Figure 2

Types of Complementary and Alternative Medicine Used by U.S. Consumers. (Data from Tindle HA, Davis RB, Phillips RS, Eisenberg DM. Trends in use of complementary and alternative medicine by US adults: 1997–2002. Altern Ther Health Med. 2005 Jan-Feb;11[1]:42–9.)

Figure 3

Adverse Effects of Herbal Products. Adverse effects of, A, Herbal products and, B, ephedra are underreported to the U.S. Food and Drug Administration. (Data from Litovitz TL, Klein-Schwartz W, Rodgers GC Jr, Cobaugh DJ, Youniss J, Omslaer JC, et al. 2001 Annual report of the American Association of Poison Control Centers Toxic Exposure Surveillance System. Am J Emerg Med. 2002 Sep;20[5]:391–452.)