Sunny Linnebur, PharmD, FCCP, BCPS, CGP
University of Colorado Skaggs School of Pharmacy and Pharmaceutical Sciences
University of Colorado Anschutz Medical Campus
Q: What is an herb?
A: An herb is a dietary supplement that is a plant or plant part with medicine-like properties that is intended to maintain or improve health. Herbs may also be called botanical products or phytomedicines. According to the Dietary Supplement Health and Education Act (1994), a dietary supplement contains one or more dietary ingredients, is intended to be taken by mouth ( pill, capsule, tablet, or liquid), and is labeled on the front panel as a dietary supplement.
Q: How are herbs commonly sold and prepared?
A: Herbs are sold as fresh or dried products, liquid or solid extracts, tablets, capsules, powders, or tea bags. A particular group of chemicals or a single chemical may be isolated from a plant and sold as a dietary supplement.
There are a number of ways to prepare and take herbs.
- A tea or infusion is made by adding boiling water to fresh or dried herbs and steeping them.
- A decoction is a preparation of roots, bark or berries that are simmered in boiling water for a longer period of time than tea. The tea or decoction may be drunk either hot or cold.
- A tincture is made by soaking an herb in alcohol and water.
- An extract is made by soaking the herb in a liquid that removes specific types of chemicals. The liquid can be used as is or evaporated to make a dry extract for use in capsules or tablets.
Q: How do you determine the quality of herbal products?
A: Standardization is a process to ensure that all batches of a specific herbal product are consistent. In the US, herbs are not required to be standardized and there is no legal definition for standardization for herbal products. Thus, standardization may mean many different things and some manufacturers use the term incorrectly. The presence of the word “standardized” on a supplement label does not necessarily indicate product quality.
Currently the best way to assure high quality herbal products is to look for certification by one or all of the following groups on the label: United States Pharmacopeia (USP); NSF International (NSF); or National Nutritional Foods Association (NNFA). These independent companies will check the product for contaminants, test for accuracy of labeling, visit the place where the herbs are manufactured and verify good manufacturing practices.
Q: Are botanical dietary supplements safe?
A: The action of herbs ranges from mild (example: chamomile and peppermint) to powerful (example: kava). Those with mild action may have subtle effects and may have to be taken for weeks or months before their full effects are achieved, while more powerful herbs may produce effects after several doses.
The dose and form of an herb also plays a role in safety. It is important to follow the manufacturer's suggested directions for using an herb. Do not exceed the recommended dose without the advice of a health care provider.
All herbs must be packaged with a “Supplement Facts” label which describes all ingredients, the serving size, and directions for use. You should carefully read this label before determining whether to purchase the product.
Q: Can I take herbal supplements if I am taking other medicines?
A. One key concern for older adults is whether an herb will interact with prescription medications- resulting in adverse effects. The drug most likely to interact with herbs is the blood thinner warfarin. If you are taking warfarin, always consult your physician before beginning any herbal product. The herb most likely to interact with medications is St. John’s Wort, which is used for mild depression. If you are taking any medications and are considering the use of St. John’s Wort, consult your physician or health care practitioner.
Some herbs can have unwanted effects before, during, and after surgery and so it is important to inform your healthcare professional about all herbs you are taking -- well before surgery. For example, gingko biloba is a mild blood thinner and may result in excessive bleeding related to surgery. You may be asked to stop taking these products 2-3 weeks before surgery to avoid potentially dangerous supplement/drug interactions - such as changes in heart rate, blood pressure, or bleeding that could negatively affect the outcome of your surgery.
Last Updated March 2012