TUESDAY, July 10, 2001 (HealthDayNews) -- Herbal supplements and surgery don't mix, say researchers who have devised new recommendations for people who use some popular products and are about to go under the knife.
The researchers found that the most frequently used herbal remedies, including echinacea, St. John's wort, ginseng, kava, gingko, and garlic, can be the most deadly if taken before surgery.
"Our intent is not to scare people with our findings, but to help them use herbal remedies more safely," says Dr. Jonathan Moss, a professor of anesthesia at the University of Chicago and co-author of a new study reported in the July 11 issue of the Journal of the American Medical Association.
"Our goal is to encourage patients to be honest with their doctors about what they are taking, and to make certain that they stop the drugs early enough before surgery takes place," Moss says.
"We published a paper on this subject as well, and our findings were similar," says Dr. Mehmet Oz, assistant professor of cardiac surgery at Columbia-Presbyterian Medical Center in New York City and co-founder of the hospital's complementary medicine program. "Herbs are medicines, and some can have a profound effect when mixed with other medications, particularly those used before, during and after surgery."
Organizations such as the American Society of Anesthesiologists has previously suggested that patients stop all herbal remedies at least two weeks prior to surgery.
But Moss says the need for surgery often can arise sooner than that. "This is particularly true of any emergency procedures, or even dental surgery," he says.
Even when surgery is scheduled in advance, Moss says patients often don't get their pre-op exam or meet with an anesthesiologist until a day or two before the operation, and that can leave a dangerous gap in communication about supplement use.
"By the time the anesthesiologist comes into the picture, there may not be sufficient time for the herb to clear from the body prior to surgery," says Moss.
And even when doctors do ask patients about herbal use, many patients are reluctant to tell the truth, fearing the physician won't approve, says Oz.
"In our study we found that patients often believed the doctor didn't know anything about herbs, so they didn't bring it up," says Oz. "Or they were afraid they would insult the doctor by admitting they were self-treating, so they didn't talk about it."
The latest study looked at eight popular herbal remedies, including the biology of the compounds and a review of all studies, case reports and any research papers that addressed safety and pharmacological effects.
The findings include a list of concerns and recommendations for pre-operative patients:
Echinacea
Concerns: allergic reactions, affects immunosuppressive drugs; impairs wound healing.
Recommendation: discontinue as far in advance of surgery as possible, particularly if liver dysfunction or an organ transplant is involved.
Ephedra (ma huang)
Concerns: increases risk of heart attack, heart rhythm abnormalities, stroke and interaction with other drugs.
Recommendation: discontinue at least 24 hours before surgery.
Garlic
Concerns: increases risk of bleeding, particularly if anti-clot medications are used.
Recommendation: discontinue at least seven days before surgery.
Gingko
Concerns: increases risk of bleeding; interferes with anti-clot medications.
Recommendation: discontinue at least 36 hours before surgery.
Ginseng
Concerns: reduces blood sugar levels; increases risk of
bleeding; interferes with warfarin, a popular anti-clot medication.
Recommendation: discontinue at least seven days before surgery.
Kava
Concerns: increases sedative effects of anesthesia; risks of addiction, tolerance and unknown withdrawal effects.
Recommendation: discontinue at least 24 hours before surgery.
St. John's wort
Concerns: alters metabolism of many other drugs.
Recommendation: discontinue at least five days before surgery.
Valerian
Concerns: could increase effects of sedatives; long-term use could decrease the amount of anesthesia normally used; severe withdrawal symptoms.
Recommendation: if possible, taper dose in weeks before surgery, or continue use until surgery and medically treat withdrawal symptoms.
Although the recommendations are based on analytical studies, the researchers say no hard and fast rules apply in the sometimes chancy world of herbal supplements.
"There is no standard dosage that consumers can rely on. Every crop is different, every product is different, so it's very difficult sometimes to know the exact way an herb is going to affect someone having surgery," says lead study author Dr. Chun-Su Yuan, assistant professor of anesthesiology and associate director of the Tang Center for Herbal Medicine Research at the University of Chicago.
That's why the researchers say you should be honest with your doctor about what you are taking.
What To Do: For more information on the safe use of herbal medicines, the study authors suggest visiting the
National Center for Complementary and Alternative Medicine, HerbMed, or the Food and Drug Administration's Center for Food Safety & Applied Nutrition.
