A new review of the herbal remedy Echinacea reveals its pros and cons, writes Sylvia Thompson.
Taking the herbal remedy Echinacea can reduce the chances of catching a cold by more than 50 per cent, according to a review of 14 studies published in this month's Lancet Infectious Diseasesjournal.
The report in the highly respected medical journal also found that by taking Echinacea, one can reduce the duration of a cold by about one and a half days.
"These results are a vindication for the use of Echinacea in the treatment of the common cold," says Ingrid Hook, senior lecturer in the School of Pharmacy, Trinity College Dublin.
"This review seems to be more in-depth and more professionally put together than previous reviews - some of which had more negative conclusions about Echinacea."
Medical herbalist Rosari Kingston says often a single trial is too small on its own to get an overall picture of the effectiveness of a herb. "The fact that this study reviewed the evidence of 14 previously published studies is significant," she says.
The study found that when used to ward off illness, adults taking Echinacea contracted one to two colds a year, instead of the typical two to four colds. Taken as a treatment for a cold, the researchers found that Echinacea reduced the average length of colds to four to six days from five to seven days.
The review was carried out by a group of researchers, led by Dr Craig Coleman, assistant professor of pharmacy practice at the University of Connecticut and at Hartford Hospital, Hartford, Connecticut, in the US.
Coleman says, however, the analysis shows that Echinacea is less effective against rhinovirus than other cold viruses. "This is a shortcoming which could limit the herb's usefulness because rhinovirus is the most common cold virus," he says.
Rhinovirus aside, there are other important issues to consider before we all rush out to stock up on Echinacea remedies, many of which are available as over-the-counter products and don't require a prescription from a GP or medical herbalist.
"Large-scale studies will now be needed to find out the dosage of Echinacea required for treatment and prevention of colds and the species type of Echinacea which works best," says Hook.
There are three different species of Echinacea that are most commonly used medicinally.These are Ecinacea purpurea, Echinacea pallida and Echinacea angustifolia.
There are varying views and research findings on whether the root or aerial (flower, stem and leaves) are the most effective parts of the herb. Views also differ on whether the herb is best used in tincture form (made from fresh herb) or dried.
Kingston says that finding the correct dosage for individual patients is another ongoing concern.
"The over-the-counter preparations of Echinacea are usually a very low dose which leads some people to say that it doesn't work. As a medical herbalist, I will often prescribe up to six millilitres a day [ equivalent to 900 drops] for acute conditions whereas about 20 drops a day is often suggested in the over-the-counter remedies."
Kingston is also concerned that if Echinacea is used too frequently in the prevention of colds, it could limit its value for more acute usage. "If you take Echinacea continuously, your body will get too used to it and it may not be as powerful in situations where you might need it more," she says.
Quality control in preparing the herb for medical preparations is also crucial.
The lack of regulations for herbal medicines in Ireland and Britain makes it very difficult for the consumer to know what they are getting, according to Dr Jen Tan, medical director of Bioforce UK, a leading manufacturer of herbal medicines.
"In countries such as Switzerland and Germany, all over-the- counter herbal medicines, homeopathic medicines and food supplements are registered and licensed but in Ireland and Britain, there is no legislation at present and manufacturers don't need to be experts at what they do," he says.
Tan advises consumers to ask health store owners about the manufacturers of different products.
"What people must do at the moment is look behind the brand and find out if the company has a certificate of good manufacturing practice."
The Traditional Herbal Medicines Directive, which is expected to be introduced in 2011, will change things radically. Once introduced, all herbal medicine manufacturers will have to apply to the Irish Medicines Board for a licence before selling their products.
In the meantime, it's buyer beware.
"The best thing people can do when choosing Echinacea products is buy from reputable manufacturers such as Bioforce and Irish Organic Herbs or seek the advice of a medical herbalist," says Kingston.
REMEDY FACTS
•What is it?
Echinacea is a native American plant which was widely used by the Native American Indians for the treatment of digestive, respiratory and urinary tract conditions. It was also used externally for snakebites, burns, wounds and bruising.
•When was it introduced into Western medicine?
Echinacea caught the attention of orthodox American doctors in the 19th century. It went out of favour in the early 20th century but came to prominence again in the 1950s when Swiss researcher Alfred Vogel spent time with the Sioux Indians and returned to Switzerland with Echinacea seeds for planting.
•What is it used for today?
Echinacea is widely used as an over-the-counter herbal remedy for the treatment and prevention of the common cold. Medical herbalists use Echinacea in much stronger dosage in the treatment of a number of viral and bacterial infections.
•How does it work?
The exact mechanism is still unclear. However, recent research has found that constituents in Echinacea called alkamides have been shown to possess stimulatory effects on phagocytosis, a process which aids the immune system in fighting bacteria.