Some Old Cautions
Medicinal herbs with established histories of producing serious side effects are best used only under the supervision of a professional health care practitioner who is knowledgeable about herbs. Lobelia and pokeweed, a strong antiviral agent that stimulates the immune system, are two classic examples. Both irritate the digestive tract, cause vomiting and decrease respiration. The FDA restricts lobelia's general use, but does permit the sale of pills to help stop smoking. Pokeweed leaves are sometimes eaten as a wild vegetable, but in 1981 a group of campers became ill hours after dining on them, even though they had boiled the leaves twice.