It can have very serious effects on heart disease, high blood pressure, and diabetes. It should never be taken with certain antidepressants, especially MAO inhibitors. Chaparral is another herb touted to work as a pain reliever and even an anticancer agent. If taken in too large a dose or for extended periods it can cause liver and kidney damage. In persons allergic to ragweed, Chamomile tea can cause a severe allergic reaction.
Many herbal products contain more than one herb.
It is important to read the label to insure you are not getting one of the unhealthy herbs. This is not an all inclusive list, if you have any questions or doubts about a particular product ask your physician or pharmacist for more information.