Echinacea has little impact on colds

Scientists say that the herbal remedy, echinacea, has little effect on the common cold.

They say the plant extract has minimal impact in reducing the severity of symptoms or shortening the duration of the common cold.

The researchers at the American College of Physicians reached their conclusion after using the herb in a study involving more than 700 people between the ages of 12 and 80. All participants had very early symptoms of a cold.

The cold volunteers were divided into four groups. The first group were left untreated, a second group were given a pill they knew contained echinacea, and a third group was given either echinacea or a placebo (dummy pill), but they did not know which.

They then recorded their symptoms twice a day for the duration of the cold, up to two weeks.

Patients who were given echinacea saw the duration of their cold reduced by seven to 10 hours. But this was not regarded as a statistically significant amount of time.

The echinacea did not significantly affect the severity of symptoms.

"Trends were in the direction of benefit, amounting to an average half-day reduction in the duration of a week long cold or an approximate 10 per cent reduction in overall severity," said Professor Bruce Barrett at the University of Wisconsin, who led the study.

However, he also added that as there were no side effects seen, there was no reason for those blighted by the cold to stop using echinacea if they think it helps them.

This article was published on Tue 21 December 2010