Preoperative use of herbal medicines: a patient survey

There has been recent concern in the media over the possible detrimental effects of herbal medicines on the perioperative period. Perceived by the public as 'natural' and therefore safe, herbal remedies may have led to adverse events such as myocardial infarction, bleeding, prolonged or inadequate anaesthesia and rejection of transplanted organs. In addition, herbal remedies can interact with many drugs given in the perioperative period. In this article we summarize the potential perioperative complications that can occur.

In order to determine the extent of use of herbal medicines, we conducted a survey of patients presenting for anaesthesia. During a 3-month period, patients were directly asked by anaesthetic staff if they were currently self-administering herbal medication.

Of 2723 patients, 131 (4.8%) were taking one or more herbal remedy. In only two cases was this recorded in the patients' notes. Women and patients aged 40-60 yr were most likely to be taking a herbal product (P<0.05 and P<0.001 respectively). The most commonly used compounds were, in descending order, garlic, ginseng, ginkgo, St John's wort and echinacea.

Self-administration of herbal medicines is common in patients presenting for anaesthesia. Because of the potential for side-effects and drug interactions it is important for anaesthetists to be aware of their use.