Unless specifically queried about their use of complementary and alternative medicine (CAM), patients may not volunteer such information to their doctors. Increasing evidence indicates that certain CAM remedies and supplements may interact with prescription drugs and anesthetic agents, complicating care for these patients. To quantify use of herbal remedies and vitamins in the presurgical population of a large tertiary center, Tsen et al.  distributed a one-page questionnaire to all patients presenting for preoperative clinical evaluation.

The questionnaire surveyed patient use of prescription and nonprescription medications and herbal remedies. A specific list of 17 commonly used herbal remedies was provided, and patients also had the opportunity to write in any remedies not listed. During the 11-week survey period, 3,842 patients were evaluated in the preoperative clinic. Of the 81% (3,106) of patients who responded, 22% reported use of herbal medications, and 51% reported taking vitamins. Women tended to use herbal medicines more frequently. The most commonly used herbal remedies included echinacea, Gingko biloba , St. John’s wort, garlic, and ginseng. Even though this survey was limited by its dependence on self-reporting, the authors emphasized that anesthesiologists must facilitate communication with patients regarding possible use of CAM remedies. Providers may wish to familiarize themselves with CAM remedies (the authors furnish several reputable Web sites) because some of these substances can cause interactions with other agents. Further study could provide definitive patterns of patient use of CAM and an understanding of the possible interactions during the perioperative period.