Am Fam Physician. 2003;67(1):83
What is echinacea?
Echinacea (say this: eck-in-ay-sha) is an herbal remedy that may help the body defend itself from the viruses that cause colds, sore throats, and the flu. Echinacea products can be found in most drug stores or health food stores.
How should I use echinacea?
Follow the directions on the package label or talk to your doctor before you buy a product. Don't take it on an empty stomach—echinacea should be taken with food or a large glass of water. Do not take echinacea for more than two weeks without consulting your doctor.
Are there any side effects?
Minor side effects are usually an upset stomach, nausea, and dizziness. Serious side effects include worsening of asthma symptoms and allergic reactions such as rash, swelling, and difficulty breathing. Talk to your doctor right away about any side effects you are having.
Who should not take echinacea?
If you are regularly taking other medicines, check with your doctor before taking echinacea. You should also tell your doctor if you drink beverages with caffeine or alcohol, if you smoke, or if you use illegal drugs. These may affect the way echinacea works.
Echinacea may not be helpful if you have any of the following conditions: an autoimmune disorder (such as lupus), human immunodeficiency virus (HIV) infection, or acquired immunodeficiency syndrome (AIDS). If you are pregnant or breastfeeding you should talk with your doctor before you start taking echinacea.
If you have a history of allergy to daisies, ragweed, marigolds, chrysanthemums, or related plants, you may be more at risk of having an allergic reaction to echinacea.