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Taking herbs? It could be an Rx for disaster

More and more people are taking so-called “supplements.” Phil Lempert prescribes caution, particularly when also taking drugs.

In an ideal world, everyone would have access to and eat a full range of healthful foods: vegetables, fruits, grains, and proteins.

But even for the most dedicated among us, a well-balanced diet is not always possible. Our lives are filled by over-scheduling, erratic eating times, and, too often, confusion about what and what not to eat for a healthful diet. In addition, many people want to avoid manufactured drugs and use remedies based on herbs instead.

So it's natural that millions are supplementing their diets with vitamins, minerals and other “health food” substances, such as botanicals, enzymes, animal extracts, herbs and amino acids. While officially not allowed to be claimed as preventing or curing diseases, these supplements are often touted as being necessary for healthy living. In some cases they may be helpful; for the most part, they are not necessary at all — and in a few instances, particularly when interacting with pharmaceuticals, they may actually be dangerous.

Before supplementing your diet with these items, check with your doctor, nutritionist or pharmacist. The foods you eat may well be enough to satisfy your body’s needs.

For example, if you eat yogurt, which is highly beneficial because of the “good” bacteria it contains, it is probably unnecessary to supplement it with acidophilus tablets. And if you eat garlic, ginger and/or ginseng — all roots that can aid digestion and add flavor to dishes — there is little, if any, need to add to your intake in supplement form.

That said, such “double-dosing” is not usually dangerous — just a waste of money. Much more troubling is the potential for bad interactions with some prescription drugs.

Claims for botanicals range anywhere from aids to digestion to helping menopausal symptoms, impotence, arthritis, and fighting the flu and colds. Before you buy them, do a bit of research. Talk to your health professional and then decide whether you need supplements, which ones, and whether they are genuinely necessary to sustain or improve your health.

Many herbal supplements are fine by themselves, but should NOT be used with prescription drugs. Prescription drugs that should NEVER be used with herbals or herbal supplements are those for blood pressure, diabetes, heart disease, liver disease or MAOIs (mononamine oxidase inhibitors, usually used for the treatment of depression). It is also important to avoid vitamin E, gingko biloba or common anti-inflammatories such as ibuprofen, naproxen or aspirin when using prescription blood-thinning drugs, especially Coumadin.

Prescription drugs for depression, seizures, HIV, heart disease or cancer should never be taken with St. John’s Wort, an increasingly popular herbal remedy for mood disorders (and one of the few over-the-counter supplements that serious medical researchers believe to be effective). Among the supplements to avoid when taking prescription drugs for menopause, impotence or the diseases listed above are: black cohosh, dong quai, echinacea, ephedra, feverfew, gingko biloba, goldenseal, guarana, kava, milk thistle, saw palmetto and Scotch broom.

It is interesting to note the herbs listed above are, like St. John’s Wort, among the more effective supplements around — which helps explain their potential to interact with prescription drugs. In other words, like conventional drugs, they have an effect on the body.

Herbs, of course, have been used as medications for millennia, for most of that time under the guidance of herbalists schooled in their applications and effects. So, recognizing their power is important, and respecting how they can interact with prescription drugs is vital to anyone who values their physical and mental health.

The more common results are stroke or internal bleeding, psychotic episodes or severe memory loss. And, at the very least, the effectiveness of the prescription drugs is aborted. At worst, bad interactions can result in death.

More information

  • FDA’s Center for Food Safety and Applied Nutrition:
  • Office of Dietary Supplements:
  • Office on Women's Health, DHHS:
  • U.S.D.A. Food and Nutrition Information Center:
  • American Pharmacists Association:

Phil Lempert is food editor of the “Today” show. He welcomes questions and comments, which can be sent to