Echinacea is an herbal remedy. For centuries, people have used Echinacea to treat the common cold. It is believed that the plant can boost the immune system and reduce the severity or duration of cold symptoms. Interestingly, Echinacea is one of the best-selling herbal products in the United States.

What Is Echinacea?

A flowering plant that grows throughout the U.S. and Canada, the nine species of Echinacea are known by names such as purple coneflower or black-eyed Susan. The entire plant, including the leaves, stems, flower, and roots, is used to produce supplements, liquid extracts, and teas.

Echinacea for the Common Cold: Does It Work?

Various studies of Echinacea as a treatment for the common cold have been performed but with mixed results. The studies have shown that it does have an effect on the immune system by increasing the number of white blood cells and by boosting the activity of other immune cells.

These effects, however, may not translate into an actual benefit when it comes to fighting the common cold. A study by the New England Journal of Medicine in 2005 found that Echinacea was no more effective than a placebo in preventing cold and did not reduce the severity of cold symptoms. Also, two studies that were funded by the National Center for Complementary and Alternative Medicine found no benefit from Echinacea in the treatment of the common cold in either children or adults.

On-the-other-hand, there are many variables to consider when studying Echinacea for the common cold. These studies have not only looked at different types and strengths of Echinacea, but at different parts of the plant or root as well, which makes it difficult to compare the results. It is very possible that some formulations are better than others and that Echinacea may help against some viruses that cause colds but not others.

Are There Side Effects of Echinacea for the Common Cold?

Although research on the benefits of Echinacea for cold treatment has provided mixed results, all agree that the risks seem to be low. The most common side effect is an upset stomach, but in some cases people have had allergic reactions to Echinacea. This can cause rashes, worsening asthma (if you have asthma), and anaphylaxis (a life-threatening emergency that can cause difficulty breathing).

If you are allergic to other plants in the daisy family, including daisies, ragweed, chrysanthemums, and marigolds, you may be at a higher risk of having an allergic reaction to Echinacea. Also Echinacea may not be safe for people who use certain drugs, such as drugs used for heart problems (like Cordarone and Pacerone) and some anti-fungal medicines. Some studies have shown that the combination of Echinacea and these drugs could cause liver damage.

Some experts recommend that those taking Echinacea should limit their usage to no more than eight weeks at a time. Although there is no evidence that the herb causes harm after this point, there is also no information about its long-term safety. Because herbal remedies, like Echinacea, are not regulated in the U.S. the way medications are, a supplement bought at the drugstore may not actually have what the label says it does.

Other Types of Alternative Treatment for the Common Cold

Many other herbs, plants, minerals, vitamins, and supplements are said to help symptoms of the common cold. These include eucalyptus, garlic, honey, lemon, menthol, vitamin C, and zinc.

If you are interested in using Echinacea for the common cold—or another alternative treatment—talk to a Riordan Clinic physician today. Remember that herbal remedies carry risks (just as any drug does) and can cause side effects or interact with other medications. Make sure that your doctor is aware of every alternative treatment that you use.