Today, an alcohol-based extract of the over ground portion of the plant or capsules of the plant are taken internally. These are said to stop the common cold and sore throat. It is used as a dietary supplement. Echinacea may have properties that boost immunity for battling upper respiratory infections, fighting infections, and relief of swelling or pain, thus curing colds. But so far the research is inconclusive.
Most studies show no benefit as a preventative for respiratory illness.
Some studies say there is good evidence that echinacea works as a treatment for respiratory illnesses. Others show no difference between the extract and a placebo. Part of this difference may be due to the use of different plants contained in the mixture or the presence of non-functional additives. So far research has not identified an individual compound as responsible for the effects of this supplement. It may require a combination of properties to get the desired effect.