BACKGROUND:Eleuthero is the shortened name for Eleutherococcus senticosus, which has also been called Siberian ginseng. Because the plant is unrelated to "true" ginseng, and the chemical ingredients are different, the name eleuthero is increasingly preferred.
The connection with Siberia developed because research on the plant was first conducted in the former Soviet Union after the second World War. Soviet researchers were searching for something to help troops withstand the harsh winters and stressful military situations.
The term “adaptogen” was proposed by their scientists for a substance that helps the body adapt to various types of stresses, whether environmental or illness related. The term has generally been confined to herbal remedies that are free of side effects and bring about very generalised benefits. Eleuthero was the most extensively studied adaptogen, with claims that almost 1,000 studies were conducted prior to the collapse of the Soviet Union.
While eleuthero has been used for many different conditions, its reputation continues to focus on the treatment of the common cold and the flu. This relates to a presumption that adaptogens support the immune system to fight off cold and flu symptoms. Eleuthero has also been recommended to overcome fatigue, which can be a factor in colds and flu.
EVIDENCE FROM STUDIES
While eleuthero has been studied extensively, much of the research is not available outside the former Soviet Union. What has been translated has had inconclusive findings and some has been of questionable quality. Many of the early studies were conducted with Soviet soldiers and elite athletes, and more recent studies have found no benefit from using eleuthero during high-intensity training.
The use of eleuthero for colds and flu has received renewed interest because of research with one specific product. The Swedish Herbal Institute developed an adaptogen product containing standardised extracts of eleuthero along with Andrographis paniculata. Although not widely used outside Asia, this herb has a reputation for relieving sore throats and treating fevers. The Swedish product, called Kan Jang, contains the two herbal extracts combined in a specific ratio.
The company has conducted several controlled trials, the results of which have been generally supportive of the effectiveness of Kan Jang for cold and flu symptoms. The first studies were small, but more recent ones have involved more than 200 participants. The results were based on patients’ subjective reports, which have limitations compared with more objective measures of effectiveness.
In general, participants reported few differences compared to the placebo in the first couple of days, but by day four or five significant beneficial effects were found. The percentage improvements were not reported.
PROBLEMATIC ASPECTS
Eleuthero has not been found to cause serious adverse effects, either alone or in combination with Andrographis. In a very small number of people, diarrhoea, sleep disturbances or headaches were reported. Concerns were raised in the 1990s about adverse effects from eleuthero. However, it turned out that the products raising concerns did not contain Eleutherococcus senticosus but were adulterated with another Chinese herb known to cause adverse effects.
RECOMMENDATIONS
Colds and flu are common reasons for absenteeism from schools and work. Increased awareness of the problems, and lack of benefit, from using antibiotics for viral infections has led to renewed interest in alternative treatments. While Echinacea remains the most commonly recommended herbal remedy for the common cold, one study found that Kan Jang was more effective than Echinacea.
At the same time, the number of studies which examined this product is small, and further independent research is needed to confirm the results. Nonetheless, the results for the combination product are encouraging. The manufacturers note that their product relieves symptoms and does not eliminate the underlying viral infection.
Dónal OMathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University
