May 16, 2012
Echinacea was the main medicinal herb used by Native Americans in the Great Plains region. Since the late 1930s, German researchers have studied echinacea and its effects on the immune system. Echinacea is one of the most frequently sold herbs in the United States.
The German government has approved Echinacea pallida root and Echinacea purpurea leaf for use against colds, flu, and chronic respiratory or urinary infections. Many studies support its use. However, a U.S. study in 2006 found no benefits from one particular preparation.
The suggested dosage of echinacea depends on which species and which parts of the plant were used. In general, it should not be used for more than 1-2 weeks at a time.
Echinacea stimulates the immune system. It promotes CD4 cell activation and increases the activity of the immune system. It helps white blood cells attack germs. These effects may decrease if people take echinacea for more than a few weeks.
Echinacea is generally not recommended for use by people with diseases of the immune system such as HIV, multiple sclerosis, or tuberculosis. The German government recommends against using echinacea if you have these conditions. Some researchers believe that echinacea could actually worsen these immune system problems.
Some doctors believe that it is not a good idea to stimulate the immune system in people who have some type of immune disorder. Increasing the activation of CD4 cells could give HIV more "target cells" to infect. Other doctors believe that some parts of the immune system are already overactive, causing damage to healthy cells and tissues.
They are also concerned about an animal study showing that echinacea increased levels of tumor necrosis factor alpha (TNF-alpha), a substance produced by the immune system to kill unhealthy cells. High levels of TNF-alpha have been linked to the progression of HIV disease.
Unfortunately, as with most herbal products, there is no careful research in people with HIV. There is no published research to document any dangerous results from the use of echinacea by people with HIV. There is no research on the use of echinacea by pregnant women. They should be careful with tinctures due to their high alcohol content.
Some researchers believe that short-term use of echinacea (up to two weeks) to treat colds or flu does not present any serious risks to people with HIV. However, both AIDS researchers and herbalists warn against long-term use of echinacea.
Some researchers believe that echinacea's effects on the immune system might cause problems for people with HIV. However, there are no published studies showing any harmful effects from echinacea. There may be no risk from using echinacea for less than two weeks.