Journal: Curr Opin Anaesthesiol 20(4):294-299, 2007. 81 References
Reprint: Dept of Anesthesiology, LSU School of Medicine, 2020 Gravier Street, Suite 775, New Orleans, LA 70112, (AD Kaye, MD, PhD, DABPM)
Faculty Disclosure: Abstracted by R. Ouellette, who has nothing to disclose.
Over one half of Americans currently take dietary supplements, and up to 33% may be using herbals in place of prescription medications. Anecdotal reports on efficacy, heavy marketing, lower costs compared with prescription medications, and accessibility are a few of the reasons for this increase in prevalence. Such products do not require approval from the US Food and Drug Administration, and, consequently, herb-drug interactions may occur. Herbals are considered food by the Food and Drug Administration, and they do not undergo any of the vigorous tests required to achieve drug status, including ensuring specific bioavailability, standardization, limitation of adulterants, and therapeutic efficacy.
Saw palmetto is used mainly for treatment of benign prostatic hyperplasia, with free fatty acids and sterols being the main components. Adverse reactions include mild gastrointestinal symptoms and headaches. St. John's wort is used to treat anxiety, mild to moderate depression and sleep-related disorders. St. John’s wort is typically well tolerated, and associated side effects may include photosensitivity, restlessness, dry mouth, dizziness, fatigue, constipation, and nausea. Recent anesthesia case reports have implicated St. John's wort in inducing cardiovascular collapse and delayed emergence from anesthesia when combined with other medications.
Echinacea is used by many as a prophylactic and therapeutic modality for upper respiratory infections. The immunostimulatory effects of echinacea may antagonize the immunosuppressive actions of corticosteroids and cyclosporine. Echinacea may also lead to inhibition of the hepatic microsomal enzyme system.
Garlic is used for treating hypercholesterolemia, hypertension, and cardiovascular disease. Anesthesia personnel must be aware that garlic may augment the effects of warfarin, heparin, and aspirin, and may result in an abnormal bleeding time. The effect can result in increased risk for perioperative hemorrhage. Ginkgo biloba is generally used to treat intermittent claudication and vertigo, and to enhance memory. However, the activity of ginkgo against platelet activating factor has resulted in induced spontaneous hyphema, spontaneous bilateral subdural hematomas, and subarachnoid hemorrhage.
Kava kava is utilized for its anxiolytic, antiepileptic, antidepressant, antipsychotic, and sedative properties. It may react adversely with the benzodiazepine alprazolam, and other central nervous system depressants, statins, alcohol, levodopa, resulting in excessive sedation, among other side effects. Ginseng is used to increase resistance to environmental stress, promote diuresis, stimulate the immune system, and facilitate digestion. Side effects such as bleeding abnormalities secondary to antiplatelet effects, headache, vomiting, epistaxis, and hypertension have been reported. Hoodia, a dietary supplement for weight loss and appetite suppression, is new. No studies have been performed to assess its drug interactions with anesthetic or analgesic agents.
It is imperative to appreciate the effects of these supplements on patients' physiologic functions perioperatively. Education of patients regarding the serious potential drug supplement interactions should be an integral component of the preoperative assessment. |
