What is herbal medicine?
Herbal medicine, also called botanical medicine or phytomedicine, refers to the use of a plant's seeds, berries, roots, leaves, bark, or flowers for medicinal purposes. Long practiced outside of conventional medicine, herbalism is becoming more mainstream as improvements in analysis and quality control along with advances in clinical research show their value in the treatment and prevention of disease.
What is the history of herbal medicine?
Plants had been used for medicinal purposes long before recorded history. For example, ancient Chinese and Egyptian papyrus writings describe medicinal plant uses. Indigenous cultures (such as African and Native American) used herbs in their healing rituals, while others developed traditional medical systems (such as Ayurveda and Traditional Chinese Medicine) in which herbal therapies were used systematically. Scientists found that people in different parts of the globe tended to use the same or similar plants for the same purposes.
In the early 19th century, when methods of chemical analysis first became available, scientists began extracting and modifying the active ingredients from plants. In the U.S. Later, chemists began making their own version of plant compounds, beginning the transition from raw herbs to synthetic pharmaceuticals. Over time, the use of herbal medicines declined in favor of pharmaceuticals.
Recently, the World Health Organization estimated that 80% of people worldwide rely on herbal medicines for some aspect of their primary health care. In the last 20 years in the United States, increasing public dissatisfaction with the cost of prescription medications, combined with an interest in returning to natural or organic remedies, has led to an increase in the use of herbal medicines. In Germany, roughly 600 - 700 plant-based medicines are available and are prescribed by approximately 70% of German physicians.
How do herbs work?
For most herbs, the specific ingredient that causes a therapeutic effect is not known. Whole herbs contain many ingredients, and it is likely that they work together to produce the desired medicinal effect. Many factors determine how effective an herb will be. For example, the type of environment (climate, bugs, soil quality) in which a plant grew will affect its components, as will how and when it was harvested and processed.
How are herbs used?
The use of herbal supplements for medicinal purposes has increased dramatically over the past 30 years. Herbal supplements are classified as dietary supplements by the U.S. Dietary Supplement Health and Education Act (DSHEA) of 1994. The FDA defines a dietary supplement as "...any product taken by mouth that contains a so-called 'dietary ingredient' and its label clearly states that it is a dietary supplement." Per the provisions of DSHEA, herbal supplements -- unlike pharmaceutical drugs -- can be marketed without undergoing testing to prove their safety and efficacy. However, herbal supplements must be manufactured according to good manufacturing practices.
The most commonly used herbal supplements in the U.S. include echinacea (Echinacea purpurea and related species), St. John's wort (Hypericum perforatum), ginkgo (Ginkgo biloba), garlic (Allium sativum), saw palmetto (Serenoa repens), ginseng (Panax ginseng, or Asian ginseng; and Panax quinquefolius, or American ginseng), goldenseal (Hydrastis canadensis), valerian (Valeriana officinalis), kava (Piper methysticum), chamomile (Matricaria recutita), feverfew (Tanacetum parthenium), ginger (Zingiber officinale), evening primrose (Oenothera biennis), and milk thistle (Silybum marianum ).
Several herbs are often used together to enhance effectiveness and synergistic actions and to reduce toxicity. Health care providers must take many things into account when recommending herbs. For example, the species and variety of the plant, the plant's habitat, how it was stored and processed, and whether or not there are contaminants (including heavy metals and pesticides).
What is herbal medicine good for?
Herbal medicine treats many conditions, such as asthma, eczema, premenstrual syndrome, rheumatoid arthritis, migraine, menopausal symptoms, chronic fatigue, and irritable bowel syndrome, among others. Herbal supplements are best taken under the guidance of a trained health care provider. Be sure to consult with your doctor or pharmacist before self-treating. Some common herbs and their uses are discussed below.
Ginkgo (Ginkgo biloba), particularly a standardized extract known as EGb 761, appears to produce improvements in awareness, judgment, and social function in people with Alzheimer's disease and dementia. Randomized controlled studies assessing the use of ginkgo supplements for Alzheimer's disease in individuals older than 65 years have produced positive results.
Kava kava (Piper methysticum) has become popular as a treatment for anxiety, but recent reports have traced liver damage to enough people who have used kava that the U.S. Food and Drug Administration (FDA) issued a warning regarding its use, while other countries, such as Germany, France, and Canada, have taken kava off of the market. However, there is no definitive proof that kava alone is responsible for liver damage in humans. Kava has been used traditionally for thousands of years.
Saw palmetto (Serenoa repens) is used by over 2 million men in the United States for the treatment of benign prostatic hyperplasia (BPH). The evidence suggests that saw palmetto provides mild-to-moderate improvement in urinary symptoms and flow measures. Saw palmetto produces similar improvement in urinary symptoms and flow compared to finasteride (Proscar), a pharmaceutical drug used in BPH, and is associated with fewer adverse treatment events.
St. John's wort (Hypericum perforatum) is well known for its antidepressant effects. The clinical efficacy of some standardized St. John's wort standardized extracts in the treatment of mild and moderate depression has been demonstrated in about 40 controlled clinical trials.
Valerian (Valeriana officinalis) has had a long tradition as a sleep-inducing agent, with the added benefit of producing no hangover feeling the next day.
Echinacea preparations (from Echinacea purpurea and other Echinacea species) may improve the body's natural immunity. Echinacea is one of the most commonly used herbal products, but controversy exists about its benefit in the prevention and treatment of the common cold. A meta-analysis of 14 clinical studies evaluating the effect of echinacea on the incidence and duration of the common cold found that echinacea supplements decreased the odds of developing the common cold by 58% and the duration of a cold by 1.4 days.
Standardized herbal supplements are the best way to ensure proper dosages and effects similar to human clinical trials. Ask your doctor or pharmacist about which herbal supplements are the best choice for your health concerns.
Is there anything I should watch out for?
Used correctly, many herbs are considered safer than conventional medications, but because they are unregulated, herbal products are often mislabeled and may contain undeclared additives and adulterants. Some herbs are associated with allergic reactions or interact with conventional drugs. Self-prescribing herbal products will increase your risk, so it is important to consult your doctor or pharmacist before taking herbal medicines. Some examples of adverse reactions from certain popular herbs are described below.
St. John's wort causes sensitivity to the sun's ultraviolet rays, and may cause an allergic reaction, stomach upset, fatigue, and restlessness. Clinical studies report that St. John's wort also interferes with the effectiveness of many drugs, including warfarin (Couamdin, a blood thinner), protease inhibitors for HIV, birth control pills, certain asthma drugs, and many other medications. In addition, St. John's wort should not be taken with prescribed anti-depressant medication. The FDA has issued a public health advisory concerning many of these interactions.
Kava kava has been linked to liver toxicity. Kava has been taken off the market in several countries because of the liver toxicity, although the causes remain controversial.
Valerian may cause oversedation, and in some people it may even have the unexpected effect of overstimulating instead of sedating.
Bleeding time may be altered with the use of garlic, ginkgo, feverfew, and ginger, among others.
Evening primrose (Oenothera biennis) may increase the risk of seizures in patients taking drug known to lower seizure threshold, such as anticonvulsants.
Some herbal supplements, especially those imported from Asian countries, may contain high levels of heavy metals, including lead, mercury, and cadmium. It is important to purchase herbal supplements from reputable manufacturers to ensure quality. Talk to your health care provider for more information.
Who is using herbal medicine?
Nearly one-third of Americans use herbs, and it is estimated that in 1998 alone $4 billion was spent on herbal products in this country. Unfortunately, a recent study in the New England Journal of Medicine indicated that nearly 70% of individuals taking herbal medicines (the majority of which were well educated and had a higher-than-average income) were reluctant to reveal their use of complementary and alternative medicine to their doctors. Because herbal medicines contain a combination of chemicals, each with a specific action, many are capable of eliciting complex physiological responses -- some of which may create unwanted or unexpected results when combined with conventional drugs. Be sure to consult your doctor before trying any herbal products.
How is herbal medicine sold in stores?
The herbs available in most stores come in several different forms: teas, syrups, oils, liquid extracts, tinctures, and dry extracts (pills or capsules). Teas are simply dried herbs left to soak for a few minutes in hot water, while other teas are the herbs boiled in water and then strained for consumption. Syrups, made from concentrated extracts and added to sweet-tasting preparations, are frequently used for sore throats and coughs. Oils are extracted from plants and often used as rubs for massage, either alone or as part of an ointment or cream. Tinctures and liquid extracts are solvents (usually water, alcohol, or glycerol) that contain the active ingredients of the herbs. Tinctures are typically a 1:5 or 1:10 concentration, meaning that one part of the herbal material is prepared with five to ten parts (by weight) of the liquid. Liquid extracts are more concentrated than tinctures and are typically a 1:1 concentration. A dry extract form is the most concentrated form of an herbal product (typically 2:1 - 8:1) and is sold as a tablet, capsule, or lozenge.
Currently, no organization or government body regulates the manufacture or certifies the labeling of herbal preparations. This means you can't be sure that the amount of the herb contained in the bottle, or even from dose to dose, is the same as what is stated on the label. Some herbal preparations are standardized, meaning that the preparation is guaranteed to contain a specific amount of the active ingredients of the herb. However, it is still important to ask companies that are making standardized herbal products the basis for their product's guarantee. If consumers insist on an answer to this question, manufacturers of these herbal products may begin to implement more quality control processes, like microscopic, chemical, and biological analyses. It is important to talk to your doctor or an expert in herbal medicine for the recommended doses of any herbal products you are considering.
Are there experts in herbal medicine?
Herbalists, chiropractors, naturopathic physicians, pharmacists, medical doctors, and practitioners of Traditional Chinese Medicine all may use herbs to treat illness. Naturopathic physicians believe that the body is continually striving for balance and that natural therapies can be used to support this process. They are trained in 4-year, postgraduate institutions that combine courses in conventional medical science (such as pathology, microbiology, pharmacology, and surgery) with clinical training in herbal medicine, homeopathy, nutrition, and lifestyle counseling.
How can I find a qualified herbalist in my area?
For additional information, or to locate an experienced herbalist in your area, contact the American Herbalists Guild (AHG) at site at www.americanherbalistsguild.com/. To locate a licensed naturopath in your area, call the American Association of Naturopathic Physicians (AANP) at www.naturopathic.org.
What is the future of herbal medicine?
Although a renaissance is occurring in herbal medicine in the United States, the FDA still classifies herbs as dietary supplements and will not allow manufacturers to claim that their products are able to treat or prevent specific diseases. In some countries in Europe, however, herbs are classified as drugs and are regulated. The German Commission E, an expert medical panel, actively researches their safety and effectiveness.
While still not widely accepted, herbal medicine is becoming more available in medical schools and pharmacy schools as a classroom topic. This allows more health care providers to become exposed to positive and potentially negative effects of using herbal medicines as part of treatment for health conditions. Some health care providers, including doctors and pharmacists, are trained in herbal medicine. These professionals can effectively help patients integrate herbs along with lifestyle changes and conventional therapies (including prescription medications and surgery) into the individual's treatment plan.
