Herbs: Toxicities And Drug Interactions (cont.)

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Data is coming, although slowly. Dr. Lucinda Miller of Texas Tech University Health Sciences reviewed known herb-drug interactions. Her review was published for doctors in the medical journal Archives of Internal Medicine. The list that follows is derived from this article and includes summaries of various herbs with particular focus on potential herb-drug interactions.

Keep in mind that the information in the "Uses" section is for the most part unsupported by verification of scientific studies. It should be noted that simply because herbs are "natural" treatments, they are not necessarily free from side effects.


Uses: Chamomile is often used in the form of a tea as a sedative.

Reactions: Allergic reactions can occur, particularly in persons allergic to ragweed. Reported reactions include abdominal cramps, tongue thickness, tightness in the throat, swelling of the lips, throat and eyes, itching all over the body, hives, and blockage of the breathing passages. Close monitoring is recommended for patients who are taking medications to prevent blood clotting (anticoagulants) such as warfarin (Coumadin).


Uses: Largely because white blood cells in the laboratory can be stimulated to eat particles, Echinacea has been touted to be able to boost the body's ability to fight off infection.

Reactions: The most common side effect is an unpleasant taste. Echinacea can cause liver toxicity. It should be avoided in combination with other medications that can affect the liver such as ketaconazole (izoral, Extina, Xolegel, Kuric), leflunomide (Arava), methotrexate (Rheumatrex, Trexall), isoniazid (INH, Nydrazid, Laniazid).

Medically Reviewed by a Doctor on 6/13/2014