Expired CME Article

Use of Echinacea in Upper Respiratory Tract Infection

Authors: Jamal Islam, MD, MS, Ramona Carter, MD

Abstract

The significant burden of upper respiratory tract infection in adults and children, coupled with a lack of specific treatment options, invites the use of alternative therapies. Echinacea is an herb widely used for the prevention or treatment of upper respiratory tract infection. This review article examines the mechanism of action, dose, and types of Echinacea used for these purposes. The principal mode of action of Echinacea is through immunostimulation. Most Echinacea studies were done in Germany, but their results are difficult to interpret because of variability of experimental parameters. Types of Echinacea commonly used areEchinacea purpurea, E pallida, and E angustifolia. Both the plant’s upper parts and roots are used. For oral administration, tablets, extracts, fresh pressed juice, teas, and tinctures have been used. Though studies show a beneficial effect, clear conclusions and recommendations of Echinacea use cannot be made due to a lack of standard product, variability in dose, and variability in outcome measures. Therefore, well-designed studies with consistent standardized measures are required.


Key Points


* Studies on the use of Echinacea for treating upper respiratory tract infection are fraught with methodologic problems, including the type and dose of Echinacea used, time of administration, and outcomes measured.


* Studies are suggestive but inconclusive as to the benefits of Echinacea in upper respiratory tract infection.


* Because of the very low number of side effects of this herb, patients willing to try it should not be discouraged from using it, but should be educated about the lack of a consensus onEchinacea’s benefits, which is attributable to a heterogeneity of study designs.

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