Herbal Supplements & Surgery

Facing Cardiac Surgery? Ask Your Doctor about Vitamins and Supplements

  • Natural products
  • Herbal supplements
  • Alternative dietary therapies
  • Antioxidants
  • Micronutrients
  • Or plain old vitamin pills

No matter what you call them, if you take these products prior to a heart operation, they can cause real problems during or after your cardiac surgery.

If you are like millions of other Americans, you may well be taking several supplements daily for your health. Perhaps you take a simple, multivitamin pill. And garlic to help protect your heart. Or ginkgo to boost your memory power. Do you grab Echinacea to stimulate the immune system at the first sign of a cold or virus? Kava to help sleep? Vitamin E or fish oil to increase cardiac health? If so, caution is required before you have a bypass operation, valve repair, or any other type of cardiac procedure.

What's the harm? After all, these products are "natural", aren't they? Well, "natural" doesn't always mean safe. Especially when cardiac surgery is on the horizon.

According to a study in the July 11, 2001 issue of the Journal of the American Medical Association (JAMA), using herbal preparations can have serious negative impact during cardiac surgery and postoperatively. The authors examined information in the medical literature about the safety of the eight most common herbal medications in light of their use in patients undergoing surgery. The eight preparations examined studied were:

  • Echinacea
  • Ephedra
  • Garlic
  • Ginkgo
  • Ginseng
  • Kava
  • St. John's wort
  • Valerian

The researchers found complications including bleeding, cardiovascular instability, hypoglycemia (low blood sugar), changes in the effects of operative anesthesia, and changes in the metabolism of other drugs used for surgery. Previous studies of these and other natural or alternative therapies such as ginger, coenzyme Q-10, and vitamin E, have found that side effects from natural agents can be as serious as a heart attack, stroke or excess internal bleeding and can unnecessarily complicate cardiac surgery.

For example, many natural products modify the blood. In so doing they may have dangerous side effects including:

  • Decreasing the blood's ability to clot, or the amount of time clotting takes
  • Increasing internal bleeding
  • Reducing the number of cell components called platelets in the blood, or their ability to stick together (called platelet aggregation and adhesion)
  • Widening or narrowing blood vessels
  • Decreasing the viscosity (thickness) of blood

If you've been taking these kinds of preparations for some time, and haven't experienced side effects, you may be inclined to "pooh-pooh" warnings in articles such as this. But don't forget that during and after cardiac surgery you are given many other drugs you don't normally take. And these other drugs, such as pain medicine or anesthetics, may interact poorly with natural therapies.

How can something so apparently innocent be so dangerous? There are several answers. Herbal medications are unregulated in this country. That means they are not subject to controlled clinical studies, either in animals or humans, that would highlight any negative side effects. Also, the medicines' quality, ingredients and manufacturing processes are not subject to inspection by a regulatory agency such as the FDA. The medicines are sold in pills, teas, powders, liquids, extracts, tinctures and capsules which are also not regulated. So, the drugs' safety, effectiveness, contents, dosages - even the reliability of a stated expiration date - are unknowns.

The medications may interact with other nutrients in your system, with other herbal preparations you are taking, or with any prescription or over-the-counter drugs you use. The herbals may change the bioavailability of a prescription drug used during cardiac surgery or affect its efficacy. Your use of these herbals needs to be discussed with your physicians and cardiac surgeons.

For example, a natural drug could change the rate at which a conventional drug is absorbed, distributed or eliminated by the body.

As with prescription and over-the-counter drugs, any effects of herbal and dietary supplements may be influenced by your age, gender, family history and general nutritional status. Effects may vary according to whether you have other health conditions, and how those health problems are being treated.

Be sure to let your cardiologist and cardiac surgeon know well in advance of your cardiac surgery if you use any of these kinds of supplements, medicines or therapies. Even if your physicians do not request this information, bring it up. After all, everyone involved in your care wants the best possible outcome.

More and more often, Americans are reaching for alternative products in their quest for good health. Be sure that your quest doesn't take you down a dangerous path.


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Medically Reviewed

Last reviewed on 12/05/2018.

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