Herbal & Dietary Supplement Use & Anesthesia





What are herbs?

Herbs include flowering plants, shrubs, trees, moss, fern, algae, seaweed or fungus. In most cultures, including Western culture, herbs are used not only as a part of the treatment of disease, but also in the enhancement of life, physically, emotionally and spiritually. Plant parts, including flowers, fruits, leaves, twigs, bark, roots or seeds, are all considered usable.


What are dietary supplements?

By definition, a dietary supplement is a product taken by mouth and intended to supplement the diet. These products may include: vitamins, minerals, herbs or other botanicals, amino acids and substances such as enzymes, organ tissues, glandulars and metabolites.


Are they medicines?

The term “drug” comes from the ancient word for “root.” Until the 1930s, medical schools taught that plant drugs were the primary medicines available. In general, since that time, patented pharmaceuticals (prescription or over-the-counter medications) have replaced the herbs or “roots,” which were either found too weak or unsafe. Like drugs or foods, medicinal plants (herbs) and dietary products (vitamins, minerals, amino acids) have many actions in the body.


Are they safe?

Sometimes, even if you take an herb or supplement for one certain reason, there can be other unintended reactions. Natural doesn’t necessarily mean safe. Herbal and dietary products have chemical properties just as manufactured drugs do. Like anything that we ingest (eat) or apply (like a salve), there can be side effects. One of the major problems with many of the products on the market today is that the amount and the purity of their active ingredients vary so greatly from product to product. In many cases, you do not always know how much of the natural substance you are really getting in each dose or if other ingredients have been added. Another problem is determining how much of each active ingredient is really safe, particularly over long-term use. There are even case reports of contaminated herbs causing death. Also, studies are being done to see how herbals and supplements react with other medications.


Does the federal government make sure that herbs and other dietary supplements are safe?

The government regulates herbal medicines in the same way that it regulates food and nutritional supplements, but herbs and other dietary supplements do not undergo the same strict research requirements as prescription drugs or over-the-counter medications (like aspirin). Whole plants cannot be patented (meaning that no one manufacturer has exclusive rights to an herb) and therefore, non-pharmaceutical companies that produce herbal products or dietary supplements are not obligated to do the same safety research that the Food and Drug Administration (FDA) requires for prescriptions or over-the-counter medications. If the FDA has reason to suspect that an herb or dietary supplement is unsafe, then the agency may require it be removed from the market. By law, however, the FDA cannot require testing of all herbal medicines and other dietary supplements before they are put on the shelf.


Could herbal medicines and other dietary supplements affect my anesthesia if I need surgery?

Anesthesiologists are conducting research to determine exactly how certain herbs and dietary supplements interact with certain anesthetics. They are finding that certain herbal medicines may prolong the effects of anesthesia. Others may increase the risks of bleeding or raise blood pressure. Some effects may be subtle and less critical, but for anesthesiologists, anticipating a possible reaction is better than reacting to an unexpected condition. So it is very important to tell your doctor about everything you are taking before surgery.


There are thousands of herbal products and dietary supplements currently on the market. Please see the attached document for examples of some commonly used herbal and dietary products and their possible problems. Not all available products are listed. Check with your doctor if you have any questions about the prescription or nonprescription medications that you are taking.

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The ASA does not employ physician anesthesiologists on staff and cannot respond to patient inquiries regarding specific medical conditions or anesthesia administration. Please direct any questions related to anesthetics, procedures or treatment outcomes to the patient’s anesthesiologist or general physician.