HealthNews from the publishers of the New England Journal of Medicine
Few ailments are more inconvenient and
ubiquitous than the common cold. No wonder so many consumers are turning to
herbal remedies such as echinacea, with hopes that it will help them stay
healthy or get better quicker. But as the popularity of herbal treatments has grown, so has confusion about how
these remedies are best used.
Only recently have rigorous medical studies evaluating herbal products been published. In the August Journal of Family Practice, American researchers reviewed 13 European trials that tested echinacea for the common cold. Nine of these trials evaluated echinacea's effectiveness as a treatment for upper respiratory symptoms. The other four evaluated the herb's ability to prevent colds.
Of the nine treatment trials, eight found some benefit to taking echinacea. Patients in the studies had either less severe symptoms or a shorter duration of illness than people who received a placebo, especially when they took large doses of the herb early in the course of the cold. In the four prevention trials, however, echinacea did not appear to provide much benefit. Patients taking the herb to ward off a cold were just about as likely to get sick as their counterparts given a dummy drug.
The study's authors conclude that echinacea may be useful if taken at the first sign of a cold, but not when used routinely as a preventive. They recommend using the herb several times a day early in the illness and then discontinuing it as symptoms improve.
However, because there is little research comparing specific formulations, it's still not clear whether one should use extracts of the roots, leaves, or flowers or which of the three commonly used echinacea species — Echinacea purpurea, E. augustifolia or E. pallida — is most likely to be effective. People with allergies to the daisy family of plants and those with autoimmune diseases should avoid these products, as should children and pregnant women, in whom echinacea has not been studied.
© 1996-1999, content Massachusetts Medical Society. All rights reserved. As provided by U.S. copyright laws, no part of this publication may be reproduced, displayed, or transmitted in any form or by any means, electronic or mechanical, including photocopying or by any information storage or retrieval system, without the prior written permission from the Rights & Permissions Dept., Massachusetts Medical Society, 860 Winter Street, Waltham, MA 02451.