Whether or not echinacea helps prevent or treat the common cold remains under debate. Some studies have shown that the herb can make you feel better faster. Others suggest that echinacea has no impact on a cold at all. Several clinical trials have shown that people who take echinacea as soon as they feel sick reduce the severity of their cold and have fewer symptoms than those who do not take the herb. One study of 95 people with early symptoms of cold and flu (such as runny nose, scratchy throat, and fever) found that those who drank several cups of echinacea tea every day for 5 days felt better sooner than those who drank tea without echinacea.
A review of 14 clinical trials found that echinacea reduced the odds of developing a cold by 58% and the duration of a cold by 1 – 4 days. However, some experts dispute these findings claiming that there were several weaknesses in the analyses. Echinacea preparations tested in clinical trials differ greatly. It is important to choose a high quality echinacea supplement. Talk to your health care provider for recommendations.