Herbs to Use with Caution
Most herbs are not dangerous; they tend not to be as powerful as pharmaceutical drugs so they don’t have many side-effects or interactions with other herbs or drugs. But certain groups need to be particularly careful when taking herbs, such as pregnant and nursing women, individuals who suffer from liver or kidney disease, or those taking MAO inhibitors or blood-thinners. In addition, there are some herbs that do need to be used with caution. Below is a list of potentially problematic herbs, their side-effects and/or potential interactions:
Alfalfa: Used for poor digestion, water retention, arthritis, urinary disorders, high cholesterol, and arteriosclerosis, alfalfa has been used medicinally for over 1,500 years. Over-supplementation, however, can be quite serious, causing damage to red blood cells that could lead to systemic lupus erythematosus (SLE).
Comfrey: Used primarily in poultices and salves for sprains and bruises, comfrey should only be used externally. Drinking comfrey tea is not recommended, as it can cause liver damage.
Chamomile, Calendula, and Echinacea: Chamomile is used as a relaxant, Calendula for healing skin irritations, and Echinacea to boost the immune system. If you’re allergic to ragweed, though, there is a possibility you might be allergic to any one or all of these herbs. If you notice any allergic effects from taking these herbs, you should stop taking them and avoid them in the future.
Ephedra: One of the most problematic members of the herbal arsenal. A stimulant that contains ephedrine and pseudoephredrine, Ephedra is used effectively for treating asthma (primarily in Traditional Chinese Medicine, in combination with other herbs to minimize side-effects). However, it’s also used unwisely in many herbal weight loss supplements. Side-effects can include insomnia, irritability, headaches, tremors, vomiting and tachycardia. In higher doses, a drastic increase in blood pressure can result, as can cardiac arrhythmia. It’s not recommended for those who suffer from anxiety, have high blood pressure, glaucoma, or numerous other health issues. It may interact with MAO inhibitors, cardiac glycoside drugs, and other pharmaceuticals. For years, I used a Chinese herbal formula that included Ephedra to manage asthma, as prescribed by my acupuncturist. It worked well, but in my opinion, it’s not a good idea to use Ephedra unless it’s under the guidance of a licensed health care provider, such as a licensed acupuncturist.
Fennel: Fennel is well-known for improving digestion and coughs. Generally speaking, this herb doesn’t pose a problem, but there is some evidence to suggest that it might serve as a potential source for synthetic estrogen. If you suffer from or are at risk for estrogen-sensitive cancers or tumors, you might want to avoid using fennel.
Ginkgo: Used to improve cognitive function and stave off dementia, perhaps by increasing blood flow, this herb is rarely a problem. But it may interact with MAO inhibitors and anticoagulant drugs.
Ginseng: There are various subtypes of ginseng, but they are all used for the same thing, to increase energy and stamina. Ginseng may interact with caffeine, other stimulants, and anticoagulant drugs, and you should not take ginseng if you have high blood pressure, heart palpitations, insomnia, asthma, or high fever.
Hawthorn: This herb is used to treat high blood pressure and cardiac insufficiency. Do not use it, however, if you’re taking digitalis.
Kava kava: This rather famous herb is used as a relaxant and to counter anxiety. I like it because it reduces stress without making me feel gorked out. It can, though, cause liver problems. Don’t take Kava if you drink a lot of alcohol, are taking prescription drugs that are hard on the liver, or if you have liver disease; limit use to one to three months. Also be careful driving or operating heavy machinery if taking Kava kava. Excessive or long term consumption can cause yellowing of the skin which, fortunately, goes away after discontinuation of use. Rare side-effects include dizziness and vertigo.
Licorice: Used for gastric or duodenal ulcers, as well as coughs, taking too much licorice can lead to sodium retention and potassium loss, which in turn can cause water retention, high blood pressure, headaches, shortness of breath, and occasionally heart problems. Do not use licorice if you have high blood pressure, kidney problems, diabetes, liver disease, or heart disease. May interact with diuretics or digitalis.
Peppermint: Peppermint tea or peppermint lozenges are often taken for stomach upset, but don’t use this herb if you suffer from acid reflux or GERD. It has the unfortunate property of relaxing the sphincter to the stomach, which keeps our amazingly powerful stomach acid from splashing up into our esophagus.
St John’s Wort: This herb is used to treat mild to moderate depression. It can cause photosensitivity, especially in fair-skinned individuals. If you’re taking St. John’s wort, you should be careful not to spend too much time in the sun. In addition, St. John’s wort may interact with other antidepressants and narcotics; concomitant use is not advised.
Herbs with blood-thinning properties include: alfalfa, bilberry, feverfew, garlic, ginger, ginseng, ginkgo, and turmeric. If you’re on blood-thinning drugs or have surgery coming up, avoid taking these herbs.
In addition, don’t use use irritant-type laxative herbs for longer than ten days, max. These herbs include Cascara sagrada or Senna. Overuse causes potassium loss and electrolyte imbalance, which can irritate an existing bowel problem. Using them for too long can also habituate your colon so that you can’t function without them.
Because humans are so genetically and physiologically diverse, anyone can have an unusual reaction to an herb, so it’s always wise to pay attention to how you feel when you start taking something new. It’s always a good idea, too, to discuss any herbs you are taking or want to take with your primary care physician, to ensure that they don’t interact with any pharmaceutical drugs you’re prescribed, or have the potential to worsen any chronic health problems you might have.
In my next post, I’ll discuss some herbal superstars, herbs that have a well-recognized track record for successfully treating common ailments and have few, if any reported side-effects.
References:
The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines, by Blumenthal, Busse, Goldberg, Gruenwald, Hall, Klein, Riggins & Rister; published by The American Botanical Council.
Herbs for Health and Healing: A Drug-Free Guide to Prevention and Care, by Kathi Keville, Director of the American Herb Association.
The Herbal Drugstore, by Linda B. White, M.D., Steven Foster, and the staff of Herbs for Health.
Above: Rattlesnake grass! Not used as an herb as far as I know, but I sure love the way it looks.
Monday, May 17, 2010