Echinacea — Does the herbal cold remedy really work?

Staff report

The popular herbal supplement echinacea may have earned its manufacturers nearly $70 million in 1998, according to industry figures. Yet the alleged cold remedy is not scientifically proven to be effective in clinical research trials. To find out if echinacea really fights colds, a team of Health System researchers has received $2.2 million from the National Institutes of Health to conduct a three-year clinical trial.

“Part of the problem surrounding the study of echinacea is that all of the products containing it are different,” said principal investigator Dr. Ronald B. Turner, a pediatrics professor in the Division of Infectious Diseases “No one has identified an active factor yet.”

Numerous variables could influence what in echinacea works and how, Turner said. The part of the plant used, the growing conditions and season and how it is processed could all possibly affect its medicinal value. In addition, the plant has three species — each of which has a different chemical composition — that are used in products.

“If you buy Product X off the shelf today and you go back six months later and buy the same brand, it may be completely different from the first thing you bought,” Turner said. “Echinacea and other supplements present a huge problem with safety and standardization, as well as for research, because if you don’t know what’s actually in the product, studies on it can’t be standardized, and therefore cannot get consistent results.”

The study will use one crop of echinacea plants processed using three different extraction methods to produce three different concentrations. The composition of the three products has been carefully characterized in the laboratory of a leading plant chemist at the University of Graz in Austria, a subcontractor for the study. The three variations — which are identical except for their extraction methods — will be administered to study subjects.

Turner and his research team plan to recruit approximately 450 subjects for the study. One group of subjects was enrolled in May, and the next group will be enrolled in October. The volunteers are infected with a cold virus. One group is given echinacea before being infected with the cold, and another group receives it after being infected. Some subjects in each group receive a look-alike placebo, or inactive medication, instead of the echinacea so they can be compared with the group receiving the herbal supplement.

“One of the things we want to find out is whether echinacea has an effect on viral replication or on the body’s inflammatory response,” Turner said. “It may involve a combination of several factors.”

Echinacea is indigenous to the American Midwest, and was first used for medicinal purposes by Native Americans, according to ethnobotanists. White settlers adopted it as a folk remedy, and in the 20th century, it became popular in Europe.

Use of echinacea has revived during the past decade’s herbal supplement production and sales have boomed in the United States.