General Description

Lobelia is an indigenous North American annual or biennial plant with an erect, angular, hairy stem that contains a milky sap and grows from 6 inches to 3 ft in height. Numerous small, two-lipped, blue flowers grow in spike-like racemes from July to November.

Chemical Composition

Lobelia contains about 0.48% pyridine (piperidine) alkaloids composed mainly of lobeline (Figure 100-1), with lesser amounts of lobelanine, lobelanidine, and other alkaloids.¹ Other constituents include resin, gum, lipids, and chelidonic acid.²

FIGURE 100-1 Lobeline.

History and Folk Use

Lobelia was named after Matthias de Lobel (1570 to 1616), a famous French botanist and physician to the court of King James I. After chewing the plant, early settlers noted that the taste was similar to tobacco and produced effects like that of nicotine, the principal alkaloid in domestic tobacco, Nicotiana tobaccum. Native Americans also smoked the dried leaves to obtain the central nervous system effects of the alkaloids in the plant. Thus, lobelia was commonly referred to as “Indian tobacco.”

Lobelia became one of the most commonly used herbs by Thomsonians, who used it as an emetic, diaphoretic, expectorant, sedative, antispasmodic, and antiasthmatic. It has been used for the following conditions:

Thomson stated: “There is no vegetable which the earth produces more harmless in its effect on the human system, and none more powerful in removing disease and promoting health than lobelia.”³