Holistic minded pharmacists give tips for herbal safety including knowing when not to use them.
There’s no doubt that herbal remedies can make wonderful, natural treatment alternatives to conventional medicines. While an increasing number of health-care practitioners throughout the United States are incorporating herbal remedies into their practices, the primary use of herbs is still largely by self-treatment. Consumers have come to consider that herbal remedies are a safe and gentle way to treat themselves, and for the most part this is true. However, a wise consumer is one who is also aware of when not to self-treat with herbs—some of those situations follow.
Emergency medical crises
A number of acute conditions warrant immediate medical attention by trained professionals and should not be self-treated with herbs:
severe allergic reactions
chest pains/heart palpitations
severe high blood pressure
Conventional medicine excels in emergency situations and can save lives. Once the emergency is under control, herbal remedies can have a complementary role in the overall healing process.
Avoid toxic herbs
Certain herbs are toxic and, therefore, should not be taken at all, or should be taken only under the careful supervision of a well-trained, experienced practitioner. Although some of the most toxic herbs can have dramatic curative properties when used correctly, they should not be used for self-treatment. Before taking anything, read up on the herb. Don’t take anything that you haven’t investigated thoroughly first.
The following is a small sampling of dangerous herbs and their toxicities. For a more complete listing of toxic herbs, check the table of contents of your favorite herbal reference book. There may be a more complete listing of toxic herbs at the back of the book.
Blue cohosh (Caulophyllum thalictroides), not to be confused with black cohosh (Cimicifuga racemosa), has a history in both folk and Native American medicines. Although it has also been used to treat rheumatism, colic, sore throat and epilepsy, its primary use has been for the treatment of female conditions. Blue cohosh’s active constituents are quite potent and can induce labor. In addition, they may cause constriction of coronary blood vessels to the point of heart failure, as well as possible birth defects.
Mistletoe (Viscum album), a parasitic shrub, has recently been in the press due to a celebrity using it for cancer treatment. The protocol involves injectable preparations and was developed in Germany. Today, mistletoe extracts are being used for cancer treatment mainly in Asia and Europe. This drug is not available in the United States. Mistletoe tea has long been used in folk medicine to treat a range of conditions. Although the berries are well-known to be poisonous, there is some controversy over the toxicity of the leaves. Also, the composition of chemical substances found in mistletoe varies substantially depending on its host plant. For these reasons, it’s wise to seek expert advice when using this herb.
Pennyroyal (Hedeoma pulegioides) has been used to treat many ailments. The very potent pennyroyal oil has earned a reputation as an abortifacient. It is extremely toxic and may cause severe liver damage. While ingesting pennyroyal can cause a woman to abort her pregnancy, it requires near-lethal amounts to do so. It is difficult to reach adequate concentrations with tea, but ingesting small amounts of the oil will result in severe toxicity and possibly even death. It’s also worth noting that infants have been poisoned by the tea.
Rue (Ruta graveolens) has primarily been used as an insect repellent and to treat insect bites, although its effectiveness is unproven. Applying fresh rue leaves to unbroken skin can cause severe contact dermatitis, blisters, and hives due to the presence of volatile oils. Exposure to the sun following contact may worsen symptoms. Taken internally, the fresh plant may cause gastric upset.
Tansy (Tanacetum vulgare) has a long history in folk medicine in the treatment of intestinal worms. Unfortunately, it can also cause convulsions and psychosis, due to the constituent thujone. There is tremendous variability in the amount of thujone present in tansy plants, ranging from 0 to 95 percent. Without doing a chemical analysis of individual plants, it’s impossible to determine the proper dosage.
Herb drug interactions
To use herbs safely, it’s important to consider the potential of any herb interacting with prescription or over-the-counter medications. Herbs, foods, and drugs all contain chemical constituents that can interact with each other. A list of possible herb/drug interactions would fill pages!
One example of a common herb/drug interaction is taking any herb that affects blood-clotting time while also taking a blood-thinning medication. For example, a person taking a blood thinner such as warfarin may want to take a garlic supplement (Allium sativum) to lower cholesterol. But garlic is known to thin the blood; also, taken along with a prescription blood thinner, garlic could potentially cause an interaction resulting in excess bleeding. Although cooking with a little garlic is generally not a problem, therapeutic doses of garlic for those on blood thinners may not be safe.
Individuals with cardiovascular and diabetic conditions may be especially sensitive to herb/drug interactions. If you’re taking any medication for any condition, common sense caution dictates a consultation with your doctor or pharmacist before taking any herbal remedies.
Putting it all together
When used properly, herbal medicines are an ideal method for creating health in our lives. They tend to have fewer side effects than conventional medicines and are safe when used appropriately. At the same time, we must also have respect for the power of herbal medicines. When the wrong herb or dose is taken, especially in serious medical conditions, there may be deleterious consequences. Herbs can also have a negative interaction when taken with other medications, of which we pharmacists are always aware.
Because herbal medicines are sold in the United States as “food supplements,” they can easily be mistakenly considered harmless. To be a smart consumer, self-education is key. Read herbal product labels for special warnings and ingredient lists. Read herbal educational literature before you decide to self-treat. When in doubt as to whether to self-treat, check with your physician, pharmacist, or qualified health-care practitioner before taking any herbs. That’s the best way to ensure herbs for health!
Constance Grauds, R.Ph. is president of the Association of Natural Medicine Pharmacists and author of the book Jungle Medicine (Citron Bay, 2001), available at www.junglemedicine.net. Mary Kundert, Pharm.D., is a natural medicine pharmacist who consults in integrative medicine.