Lobelia Inflata

Indian Tobacco, Gagroot, Vomitroot


This plant has a straight and angular stem that is covered by tiny hairs that can grow up to three feet high. It can have pale green or yellow leaves that give off an irritating odor and a sour taste. The leaves are used medicinally but can be toxic if a person ingests a large quantity of them (“Lobelia”). As the stem branches, these branches hold sparse amount of flowers that are colored a violet blue along the outside and yellow on the inside. As an annual plant, Lobelia inflata grows during the summer and fall months of the year. Depending on where you live, it is suggested that you plant your seeds two months before the last frost and put the plant in the ground in either the months of May or June. It is a native to the eastern part of the United States down to Alabama and Kansas, it is also found in the southeastern part of Canada (“Lobelia inflata”). In the beginning of the plants life, a person must sow the seeds without covering them with soil in order for germination to take place (Sidhe). Once the flower begins to grow and the last spring frost has occurred, the plant can be placed in a garden that gets at least six hours of sunshine and time in the shade. The ground must be moist for it to thrive and it must be watered at least 2-3 times a week. When placed in the garden, Lobelia inflata is not an invasive plant, but it should be kept six centimeters apart from each other to prevent crowding (Sidhe).


Lobelia inflata contains 14 different kinds of alkaloids, the most profound alkaloid being lobeline, gums, resins, lipids, essential oil, and lobelic acid. Lobeline and the other active ingredients are found predominantly within the leaves of the plant. The most pertinent alkaloid is Lobeline and it has many biological activities. It has been seen to cause direct central stimulation of the vomiting center and it is an irritant of the GI system (Felpin and Lebreton 10127-10153). According to Felpin and Lebreton, it affects the Sympathetic Nervous System by increasing blood pressure which can lead to tachycardia. The type of receptors it affects are both cholinergic and adrenergic receptors. They also found that within the Parasympathetic Nervous System it increases salivation and diarrhea. Their research showed Lobeline becoming with the cholinergic receptors of the CNS causing memory improvement within rodents. This kind of activity has scientists/researchers finding ways to use Lobeline in treating Alzheimer’s and Parkinson’s disease

Fun Fact

Lobelia inflata has many interesting stories that are linked to it. In 1809, Samuel Thomson was charged with murdering Ezra Lovette by poisoning, though he was later acquitted. Thomson was a profound figure who used herbal medicine as an alternative way to treat people (King). Thomson was accused of murder because he used Lobelia which can be extremely toxic if ingested (King). In 1996, a Russian study found that Lobelia Inflata has a high concentration of chromium which can be helpful in treating people with chromium deficiency.


Historically, Lobelia inflata has been used by many different people in many different ways. However, the major groups of people who used this type of plant were the Native Americans. The Cherokee tribe would mash the root and the dried leaves and smoke the plant in order to help with coughing and chest pains. The Iroquois tribe used it to help treat venereal diseases, ulcers, and leg sores. They would eat the plant and apply it to the parts of their body that were in pain. The Crows used this plant throughout their religious ceremonies. However it was not until the 1800s that Lobelia inflata began to be used by physicians due to Samuel Thomson; he was a botanist and healer who used this plant as a diaphoretic and a diffusive stimulant to help treat fever, rheumatism, and the common cough.



There are many ways that people can use this plant medicinally. Lozenges are recommended to help relieve an irritable cough. Lozenges are made by adding one pint of strong acetous tincture to four pounds of white sugar and to dry in candy form (Felter, MD, and Lloyd, Phr, PhD). An acetous tincture with bayberry tea can be used to stimulate vomiting. This kind of tincture can be made with two ounces of well ground lobelia seeds, one pint of distilled vinegar, let it macerate for a week, express and filter the liquid, and add to a diluted alcohol (Felter, MD, and Lloyd, Phr, PhD). The making of acetous syrup can be used for asthma or a dry cough. This kind of syrup is made with one pint of acetous tincture in two pounds of dissolved white sugar at a gentle heat (Felter, MD, and Lloyd, Phr, PhD. According to many herbal societies, the two best ways to use this plant are through an infusion and a tincture. To make an infusion of Lobelia Inflata, it can be prepared by boiling a cup of boiling water over ¼ or ½ teaspoon of dried leaves, after the herb steeps for fifteen minutes the infusion is ready to be drunk.

Contraindications/Interactions/Adverse Reactions

References Cited

Felpin, Francois-Xavier, and Jacques Lebreton. "History, chemistry and biology of alkaloids from Lobelia inflata." Tetrahedron. 60.45 (2004): 10127-10153. Web. 14 Mar. 2012. <http://www.sciencedirect.com/science/article/pii/S0040402004012943>.


Felter, MD, Wilkes, and John Uri Lloyd, Phr, PhD. "King's American Dispensatory, 1898." Henriette's Herbal Hompage. N.p., 2012. Web. 12 Mar 2012. <http://www.henriettesherbal.com/eclectic/kings/index.html>.


King, Rosanna. "Lobelia." Dr. Christopher's Herbal Legacy. Christopher Publications, n.d. Web.   12 Mar 2012. <http://www.herballegacy.com/King_History.html>.


"Lobelia." University of Maryland Medical Center. N.p., 2011. Web. 12 Mar 2012. <http://www.umm.edu/altmed/articles/lobelia-000264.htm>.


"Lobelia inflata." Wikipedia, the free encyclopedia. N.p., 05 Mar 2012. Web. 12 Mar 2012. <http://en.wikipedia.org/wiki/Lobelia_inflata>.NO


Sidhe, Willow. "How to Grow Lobelia." eHow. N.p., 2012. Web. 12 Mar 2012. <http://www.ehow.com/how_5410381_grow-lobelia.html>.