Green tea can clash
with common drugs
Tea has been touted for its health benefits for about 5,000 years. Scientists are now identifying a multitude of chemicals in tea thought to provide health benefits from weight loss to fighting heart disease, cancer and even HIV infection.
These chemicals, however, can clash with powerful chemicals in common drugs. Green tea contains a moderate amount of caffeine and is especially high in compounds called flavonoids -- thought to be the substances that deliver a variety of the benefits. Consequently, green tea extract is showing up in a variety of dietary supplements, especially weight-loss products as a replacement for ephedra.
For most people, green tea and its components might deliver significant health benefits. But those who rely on a variety of drugs (both prescription and nonprescription) to treat medical conditions should be careful about consuming green tea or its extracts and might be wise to avoid them.
According to the eighth edition of "The Geriatric Dosage Handbook," by Todd Semla, Judith Beizer and Martin Higbee, green tea should be avoided by those taking these drugs (typical brand names with common names in parentheses):
>> Activase or Cathflo Activase (Alteplase)
>> Acular or Toradol (Ketorolac Tromethamine)
>> Advil, Midol or Motrin (Ibuprofen)
>> AKPro or Propine (Dipivefrin)
>> Amigesic or Disalcid (Salsalate)
>> Anaprox or Naprosyn (Naproxen)
>> Ansaid Oral or Ocufen Ophthalmic (Flurbiprofen)
>> Aspirin (Acetylsalicylic Acid)
>> Arixtra (Fondaparinux)
>> Arthrotec (Diclofenac or Misoprostol)
>> Bextra (Valdecoxib)
>> Clinoril (Sulindac)
>> Coumadin (Warfarin)
>> Daypro (Oxaprozin)
>> Dolobid (Diflunisal)
>> Feldene (Piroxicam)
>> Hepalean (Heparin)
>> Indocin (Indomethacin)
>> Lodine or Lodine XL (Etodolac)
>> Lovenox (Enoxaparin)
>> Miradon (Anisindione)
>> Naflon (Fenoprofen)
>> Orgaran (Danaparoid)
>> Plavix (Clopidogrel)
>> Relafen (Nabumetone)
>> Streptase (Streptokinase)
>> Ticlid (Ticlopidine)
>> Tolectin or Tolectin DS (Tolmetin)
>> Tricosal or Trilisate (Choline Magnesium Trisalicylate)
Other herbs that should be avoided by those using these drugs include cat's claw, dong quai, evening primrose, feverfew, red clover, horse chestnut, garlic, ginseng and ginkgo. Like green tea, these herbs can increase the risk of internal bleeding. Internal bleeding in the stomach or intestinal tract can lead to iron deficiency. Bleeding in the brain can cause hemorrhagic stroke.
The dosage of many of these drugs can be adjusted to allow for consistent daily drinking of green tea. Work with your physician before you increase or decrease your usual dose of green tea or green tea extract.
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Alan Titchenal, Ph.D., C.N.S. and Joannie Dobbs, Ph.D., C.N.S. are
nutritionists in the Department of Human Nutrition, Food and Animal
Sciences, College of Tropical Agriculture and Human Resources, UH-Manoa.
Dr. Dobbs also works with the University Health Services and prepares
the nutritional analyses marked with an asterisk in this section.