Echinacea

Other Name(s):

American Cone Flower, Black Sampson, Black Susans, Brauneria Angustifolia, Brauneria Pallida, Brauneria Purpurea, Comb Flower, Coneflower, Echinacea Angustifolia, Echinacea Pallida, Echinacea Purpurea, Echinacea Serotine, Echinacea Speciose, Echinaceawurzel, Échinacée, Échinacée Angustifolia, Échinacée Pallida, Échinacée Pourpre, Échinacée Purpurea, Equinácea, Fleur À Hérisson, Hedgehog, Helichroa Purpurea, Igelkopfwurzel, Indian Head, Kansas Snakeroot, Narrow-Leaved Purple Cone Flower, Pale Coneflower, Purple Cone Flower, Purpursonnenhutkraut, Purpursonnenhutwurzel, Racine D'echininacea, Red Sunflower, Rock-Up-Hat, Roter Sonnenhut, Rudbeckia Purpurea, Rudbeckie Pourpre, Schmallblaettrige Kegelblumenwurzel, Schmallblaettriger Sonnenhut, Scurvy Root, Snakeroot, Sonnenhutwurzel.

Overview

Echinacea is an herb that is native to areas east of the Rocky Mountains in the United States. It is also grown in western States, as well as in Canada and Europe. Several species of the echinacea plant are used to make medicine from its leaves, flower, and root. Echinacea was used in traditional herbal remedies by the Great Plains Indian tribes. Later, settlers followed the Indians' example and began using echinacea for medicinal purposes as well. For a time, echinacea enjoyed official status as a result of being listed in the US National Formulary from 1916-1950. However, use of echinacea fell out of favor in the United States with the discovery of antibiotics. But now, people are becoming interested in echinacea again because some antibiotics don't work as well as they used to against certain bacteria.

Echinacea is widely used to fight infections, especially the common cold, the flu, and other upper respiratory infections. Some people take echinacea at the first sign of a cold, hoping they will be able to keep the cold from developing. Other people take echinacea after cold symptoms have started, hoping they can make symptoms less severe.

Echinacea is also used against many other infections including urinary tract infections, vaginal yeast infections, herpes, HIV/AIDS, human papilloma virus (HPV), bloodstream infections (septicemia), tonsillitis, streptococcus infections, syphilis, typhoid, malaria, ear infection, swine flu, warts, and nose and throat infections called diphtheria.

Other uses include anxiety, low white blood cell count, chronic fatigue syndrome (CFS), rheumatoid arthritis, migraines, acid indigestion, pain, dizziness, rattlesnake bites, attention deficit-hyperactivity disorder (ADHD), and improving exercise performance.

Sometimes people apply echinacea to their skin to treat boils, gum disease, abscesses, skin wounds, ulcers, burns, eczema, psoriasis, sun-related skin damage, herpes simplex, yeast infections, bee stings, snake and mosquito bites, and hemorrhoids.

Echinacea is also used as an injection to treat vaginal yeast infections and urinary tract infections (UTIs).

Commercially available echinacea products come in many forms including tablets, juice, and tea.

There are concerns about the quality of some echinacea products on the market. Echinacea products are frequently mislabeled, and some may not even contain echinacea, despite label claims. Don't be fooled by the term "standardized." It doesn't necessarily indicate accurate labeling. Also, some echinacea products have been contaminated with selenium, arsenic, and lead.

How does work?

Echinacea seems to activate chemicals in the body that decrease inflammation, which might reduce cold and flu symptoms.

Laboratory research suggests that echinacea can stimulate the body's immune system, but there is no evidence that this occurs in people.

Echinacea also seems to contain some chemicals that can attack yeast and other kinds of fungi directly.

SLIDESHOW

How to Get Rid of a Cold: Natural Remedies See Slideshow

Uses

Possibly Effective for...

  • Common cold. Many scientific studies show that taking some echinacea products when cold symptoms are first noticed can modestly reduce symptoms of the common cold in adults. But other scientific studies show no benefit. The problem is that scientific studies have used different types of echinacea plants and different methods of preparation. Since the studies have not been consistent, it is not surprising that different studies show different results. If it helps for TREATING a cold, the benefit will likely be modest at best. Research on the effects of echinacea for PREVENTING the common cold is also mixed. Some research shows that taking echinacea can reduce the risk of catching a cold by 45% to 58%. But other research shows that taking echinacea does not prevent the common cold when you are exposed to cold viruses.

Insufficient Evidence to Rate Effectiveness for...

  • Anxiety. Early research suggests that taking 40 mg of a specific echinacea extract (ExtractumPharma ZRT, Budapest, Hungary) per day for 7 days reduces anxiety. But taking less than 40 mg per day does not seem to be effective.
  • Exercise performance. Early research shows that taking echinacea (Puritian's Pride, Oakdale, NY) four times daily for 28 days increases oxygen intake during exercise tests in healthy men.
  • Gingivitis. Early research suggests that using a mouth rinse containing echinacea, gotu kola, and elderberry (HM-302, Izum Pharmaceuticals, New Yok, NY) three times daily for 14 days might prevent gum disease from worsening. Using a specific mouth patch containing the same ingredients (PerioPatch, Izun Pharmaceuticals, New York, NY) also seems to reduce some symptoms of gum disease, but it is not always effective.
  • Herpes simplex virus (HSV). Evidence on the effect of echinacea for the treatment of HSV is unclear. Some research shows that taking a specific echinacea extract (Echinaforce, A Vogel Bioforce AG) 800 mg twice daily for 6 months does not seem to prevent or reduce the frequency or duration of recurrent genital herpes. However, other research shows that taking a combination product containing echinacea (Esberitox, Schaper & Brummer, Salzgitter-Ringelheim, Germany) 3-5 times daily reduces itchiness, tension, and pain in most people with cold sores (herpes labialis).
  • Human papilloma virus (HPV). Early research shows that taking a combination product containing echinacea, andrographis, grapefruit, papaya, pau d'arco, and cat's claw (Immune Act, Erba Vita SpA, Reppublica San Marino, Italy) daily for one month reduces the recurrence of anal warts in people who had surgical removal of anal warts. But this study was not high quality, so results are questionable.
  • Influenza (flu). Early research shows that taking a specific echinacea product (Monoselect Echinacea, PharmExtracta, Pontenure, Italy) daily for 15 days might improve the response to the flu vaccine in people with breathing problems such as bronchitis or asthma.
  • Low white blood cell count (Leukopenia). Early research shows that using 50 drops of a combination product containing echinacea root extracts, thuja leaf extract, and wild indigo (Esberitox N, Schaper & Brummer, Salzgitter-Ringelheim, Germany) in between chemoradiotherapy can improve red and white blood cell counts in some women with advanced breast cancer. But this effect is not seen in all patients, and doses lower than 50 drops don't seem to work. Also, this product does not seem to reduce the risk of infection.
  • Middle ear infection. Early research suggests that taking a specific liquid echinacea extract three times daily for 3 days at the first sign of a common cold does not prevent an ear infection in children 1-5 years-old with a history of ear infections. Ear infections actually seemed to increase.
  • Tonsillitis. Early research shows that spraying a specific product containing sage and echinacea into the mouth every two hours up to 10 times per day for up to 5 days improves sore throat symptoms similar to commonly used drug sprays in people with tonsillitis. Other early research suggests that taking 50 drops of a product containing echinacea (Esberitox, Schaper & Brummer, Salzgitter-Ringelheim, Germany) three times daily for 2 weeks, along with an antibiotic, reduces sore throat and increases overall well-being in people with tonsillitis.
  • Eye inflammation (Uveitis). Early research suggests that taking 150 mg of an echinacea product (Iridium, SOOFT Italia SpA) twice daily, in addition to eye drops and a steroid used to treat inflammation for 4 weeks, does not improve vision any more than eye drops and steroids alone in people with eye inflammation.
  • Warts. Early research suggests that taking echinacea by mouth daily for up to 3 months does not clear warts on the skin. But taking a supplement containing echinacea, methionine, zinc, probiotics, antioxidants, and ingredients that stimulate the immune system for 6 months, in addition to using conventional treatments, seems to work better than conventional treatments alone.
  • Urinary tract infections (UTIs).
  • Yeast infections.
  • HIV/AIDS.
  • Bloodstream infections.
  • Strep infections.
  • Syphilis.
  • Typhoid.
  • Malaria.
  • Diphtheria.
  • Migraine headaches.
  • Chronic fatigue syndrome (CFS).
  • Eczema.
  • Hay fever or other allergies.
  • Bee stings.
  • Attention deficit-hyperactivity disorder (ADHD).
  • Swine flu.
  • Rheumatoid arthritis (RA).
  • Indigestion.
  • Pain.
  • Dizziness.
  • Rattlesnake bites.
  • Other conditions.
More evidence is needed to rate echinacea for these uses.

Side Effects

Echinacea is LIKELY SAFE for most people when taken by mouth in the short-term. Various liquid and solid forms of Echinacea have been used safely for up to 10 days. There are also some products, such as Echinaforce (A. Vogel Bioforce AG, Switzerland) that have been used safely for up to 6 months.

Some side effects have been reported such as fever, nausea, vomiting, unpleasant taste, stomach pain, diarrhea, sore throat, dry mouth, headache, numbness of the tongue, dizziness, insomnia, disorientation, and joint and muscle aches. In rare cases, echinacea has been reported to cause inflammation of the liver.

Applying echinacea to the skin can cause redness, itchiness, or a rash.

Echinacea is most likely to cause allergic reactions in children and adults who are allergic to ragweed, mums, marigolds, or daisies. If you have allergies, be sure to check with your healthcare provider before taking echinacea.

Precautions

Children: Echinacea is POSSIBLY SAFE when taken by mouth in the short-term. It seems to be safe in most children ages 2-11 years. However, about 7% of these children may experience a rash that could be due to an allergic reaction. There is some concern that allergic reactions to echinacea could be more severe in some children. For this reason, some regulatory organizations have recommended against giving echinacea to children under 12 years of age.

Pregnancy: Echinacea is POSSIBLY SAFE when taken by mouth in the short-term. There is some evidence that echinacea might be safe when taken during the first trimester of pregnancy without harming the fetus. But until this is confirmed by additional research, it is best to stay on the safe side and avoid use.

Breast feeding: There is not enough reliable information about the safety of taking echinacea if you are breast feeding. Stay on the safe side and avoid use.

An inherited tendency toward allergies (atopy): People with this condition are more likely to develop an allergic reaction to echinacea. It's best to avoid exposure to echinacea if you have this condition.

"Auto-immune disorders" such as such as multiple sclerosis (MS), lupus (systemic lupus erythematosus, SLE), rheumatoid arthritis (RA), a skin disorder called pemphigus vulgaris, or others: Echinacea might have an effect on the immune system that could make these conditions worse. Don't take echinacea if you have an auto-immune disorder.

QUESTION

The common cold is one of the most common illnesses in the world. See Answer

Interactions


CaffeineInteraction Rating: Moderate Be cautious with this combination.Talk with your health provider.

The body breaks down caffeine to get rid of it. Echinacea might decrease how quickly the body breaks down caffeine. Taking echinacea along with caffeine might cause too much caffeine in the bloodstream and increase the risk of side effects. Common side effects include jitteriness, headache, and fast heartbeat.


Etoposide (VePesid)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Etoposide (VePesid) is changed and broken down by the body. Echinacea might decrease how quickly the body breaks down etoposide (VePesid). Taking echinacea along with etoposide might increase the side effects of etoposide. Before taking echinacea, talk to your healthcare provider if you are taking any medications that are changed by the body.


Medications changed by the body (Cytochrome P450 3A4 (CYP3A4) substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications are changed and broken down by the body. Echinacea might affect how the body breaks down these medications. In some cases, taking echinacea along with these medications might increase the effects and side effects of the medications. In other cases, taking echinacea along with these medications might decrease the effects and side effects of the medications. Before taking echinacea, talk to your healthcare provider if you are taking any medications that are changed by the body.

Some medications changed by the body include lovastatin (Mevacor), clarithromycin (Biaxin), cyclosporine (Neoral, Sandimmune), diltiazem (Cardizem), estrogens, indinavir (Crixivan), triazolam (Halcion), and many others.


Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications are changed and broken down by the liver. Echinacea might decrease how quickly the liver breaks down some medications. Taking echinacea along with some medications might increase the effects and side effects of some medications. Before taking echinacea, talk to your healthcare provider if you are taking any medications that are changed by the liver.

Some of the medications that are changed by the liver include clozapine (Clozaril), cyclobenzaprine (Flexeril), fluvoxamine (Luvox), haloperidol (Haldol), imipramine (Tofranil), mexiletine (Mexitil), olanzapine (Zyprexa), pentazocine (Talwin), propranolol (Inderal), tacrine (Cognex), theophylline, zileuton (Zyflo), zolmitriptan (Zomig), and others.


Medications that decrease the immune system (Immunosuppressants)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Echinacea can increase the activity of the immune system. Taking echinacea along with some medications that decrease the immune system might decrease these medications' effectiveness.

Some medications that decrease the immune system include azathioprine (Imuran), basiliximab (Simulect), cyclosporine (Neoral, Sandimmune), daclizumab (Zenapax), muromonab-CD3 (OKT3, Orthoclone OKT3), mycophenolate (CellCept), tacrolimus (FK506, Prograf), sirolimus (Rapamune), prednisone (Deltasone, Orasone), corticosteroids (glucocorticoids), and others.


Darunavir (Prezista)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

The body breaks down darunavir (Prezista) to get rid of it. Echinacea might affect how quickly the body breaks down darunavir (Prezista). Taking echinacea along with darunavir (Prezista) might increase the risk of side effects or decrease the effects of darunavir (Prezista). However, this has not been observed in humans.


Docetaxel (Docefrez, Taxotere)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

The body breaks down docetaxel (Taxotere) to get rid of it. Echinacea might affect how quickly the body breaks down docetaxel (Taxotere). Taking echinacea along with docetaxel (Taxotere) might increase the risk of side effects or decrease the effects of docetaxel (Taxotere). However, this has not been observed in humans.


Etravirine (Intelence)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Etravirine (Intelence) is changed and broken down by the body. Echinacea might affect how quickly the body breaks down etravirine (Intelence). Taking echinacea along with etravirine (Intelence) might increase the side effects or decrease the effects of etravirine (Intelence). But this has not been seen in humans.


Lopinavir / Ritonavir (Kaletra)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Lopinavir / ritonavir (Kaletra) is changed and broken down by the body. Echinacea might affect how quickly the body breaks down lopinavir / ritonavir (Kaletra). Taking echinacea along with etravirine (Intelence) might increase the side effects or decrease the effects of lopinavir / ritonavir (Kaletra). But this has not been seen in humans.


Midazolam (Versed)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Midazolam (Versed) is changed and broken down by the body. Echinacea seems to affect how quickly the body breaks down midazolam (Versed). Taking midazolam (Versed) with echinacea might increase the side effects or decrease the effects of midazolam (Versed). More information is needed to know the effects of echinacea on midazolam (Versed).


Warfarin (Coumadin)Interaction Rating: Minor Be cautious with this combination.Talk with your health provider.

Warfarin (Coumadin) is used to slow blood clotting. The body breaks down warfarin (Coumadin) to get rid of it. Echinacea might increase the breakdown and decrease the effectiveness of warfarin (Coumadin). Decreasing the effectiveness of warfarin (Coumadin) might increase the risk of clotting. Be sure to have your blood checked regularly. The dose of your warfarin (Coumadin) might need to be changed.

Dosing

BY MOUTH:

  • For common cold TREATMENT, an extract of Echinacea purpurea (Echinacin, Madaus AG, Cologne, Germany) 5 mL twice daily for 10 days has been used. An extract of Echinacea purpurea (EchinaGuard, Madaus AG, Cologne, Germany), 20 drops in water every 2 hours on the first day of cold symptoms, followed by three times daily for up to 10 days has also been used. An extract of the whole Echinacea purpurea plant (Echinilin, Inovobiologic Inc., Calgary, Alberta, Canada), 4 mL ten times on the first day of a cold, then four times daily for 6 days, or 5 mL eight times on the first day of cold symptoms, then three times daily for 6 days has been used. A tea different species of echinacea (Echinacea Plus, Traditional Medicinals, Sebastopol, CA) five or six times on the first day of cold symptoms, then reducing by 1 cup per day over the following 5 days has been used.
  • For common cold PREVENTION, a specific echinacea extract (Echinaforce, A. Vogel Bioforce AG, Switzerland) 0.9 mL three times daily (total dose: 2400 mg daily) for 4 months, with an increase to 0.9 mL five times daily (total dose: 4000 mg daily) at the first sign of a cold, has been used.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

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