• Basic Info
• Top Questions
• Interactions

Safety

DISCLAIMER: Many complementary techniques are practiced by healthcare professionals with formal training, in accordance with the standards of national organizations. However, this is not universally the case, and adverse effects are possible. Due to limited research, in some cases only limited safety information is available.

Allergies

People with allergies to plants in the Asteraceae or Compositae family (ragweed, chrysanthemums, marigolds, daisies) are theoretically more likely to have allergic reactions to echinacea. Multiple cases of anaphylactic shock (severe allergic reactions) and allergic rash have been reported with echinacea taken by mouth. Allergic reactions including itching, rash, wheezing, facial swelling, and anaphylaxis may occur more commonly in people with asthma or other allergies. Echinacea injections have caused severe reactions and are not recommended.

Echinacea has been associated with an increased incidence of rash in children, and therefore the risks of use may outweigh potential benefits.

Side Effects and Warnings

Few side effects from echinacea are reported when it is used at the recommended doses. Reported complaints include stomach discomfort, nausea, sore throat, rash (allergic, hives, or painful lumps called "erythema nodosum"), drowsiness, headache, dizziness, and muscle aches. Rare cases of hepatitis (liver inflammation), kidney failure, or irregular heart rate (atrial fibrillation) have been reported in people taking echinacea, although it is not clear that these were due to echinacea itself. Injected echinacea may alter blood sugar levels and cause severe reactions, and should be avoided. Echinacea has been associated with an increased incidence of rash in children, and therefore the risks of use may outweigh potential benefits. Thrombotic thrombocytopenic purpura (TTP) has also been reported.

Some natural medicine experts discourage the use of echinacea by people with conditions affecting the immune system, such as HIV/AIDS, some types of cancer, multiple sclerosis, tuberculosis, and rheumatologic diseases (such as rheumatoid arthritis or lupus). However, there are no specific studies or reports in this area, and the risks of echinacea use with these conditions are not clear. Long-term use of this herb may cause low white blood cell counts (leukopenia).

Pregnancy and Breastfeeding

At this time, echinacea cannot be recommended during pregnancy or breastfeeding. Although early studies show no effect of echinacea on pregnancy, there is not enough research in this area. Pregnant women should avoid tinctures because of the potentially high alcohol content.

Interactions

Interactions with Drugs

Natural medicine practitioners sometimes caution that echinacea may lead to liver inflammation. There is not clear information from laboratory or human studies in this area. Nonetheless, caution should be used when combining echinacea by mouth with other medications that can harm the liver. Examples of such agents include anabolic steroids, amiodarone, methotrexate, acetaminophen (Tylenol®), and antifungal medications taken by mouth (such as ketoconazole). Echinacea may affect the way certain drugs are broken down by the liver.

In theory, echinacea's ability to stimulate the immune system may interfere with drugs that are taken to suppress the immune system (including azathioprine, cyclosporine, and steroids such as prednisone). No clear human studies are available.

In one vague report, a person taking the antibiotic amoxicillin and an unclear echinacea preparation developed muscle damage, shock, and death.

Early information suggests that the use of echinacea with econazole nitrate cream (Spectazole®) on the skin may lower the frequency of vaginal yeast infections after treatment.

Many tinctures contain high levels of alcohol, and may cause nausea or vomiting when taken with metronidazole (Flagyl®) or disulfiram (Antabuse®).

Interactions with Herbs and Dietary Supplements

Natural medicine practitioners sometimes caution that echinacea may lead to liver inflammation. Although there is no clear information from laboratory or human studies, in theory echinacea may add to liver toxicity caused by other agents. Echinacea may affect the way certain herbs and supplements are broken down by the liver.

Echinacea is sometimes used in combination products that are thought to stimulate the immune system. For example, Esberitox® (PhytoPharmica, Germany) contains Echinacea purpurea, Echinacea pallida, wild indigo root (Baptisia tinctoria), and thuja (white cedar). Echinacea may be combined with goldenseal or other herbs in some cold relief preparations. No high quality human studies have shown added benefits or interactions of these combinations.