Great Lobelia

The Great Lobelia is an imposing flower on a tall stem, ideal for pollinators.

Common Name: Great Lobelia, Gagroot, Asthma weed– Use of the scientific genus for a common name is not unheard of in botany, but it is unusual. It would be logical but wrong to associate the name with “lobe,” a round projecting part like those of the multi-petal blossom. Since common names arise randomly as mnemonics, it is probable that the “lobe-like” name was good enough. The true etymology of the common/genus name is to honor Matthias de l’Obel, the sixteenth century Flemish physician to both Prince William of Orange and King James I of England. The two other notable flowers in the genus Lobelia that are of special note have more descriptive common names: Cardinal Flower, and Indian Tobacco.

Scientific Name: Lobelia siphilitica – The species name is recognizable as a Latinized version of syphilis, the (mostly) sexually transmitted disease (STD) that was the scourge of Europe in the sixteenth and seventeenth centuries. The plant was at one time considered a curative.

PotpourriThe “Great” Lobelia deserves the honorific reserved for historically important leaders like Alexander and imposing pyramids like Khufu by virtue of its superlative floral attributes. Up to four feet tall, it is liberally spangled with clusters of irregular blue flowers that extend outward in five pointed lobes like grasping, gloved fingers. The name lobelia evidently stuck as it is overendowed with lobes even though that has nothing whatever to do with the name, which honors the Flemish physician Matthias de l’Obel (“de le” is ”of the” in French) who wrote several books on botany with emphasis on medicinal properties. This is apropos as the other  common names gagroot and asthma weed are evidence of a deep relationship that people have historically had with this plant and its several cousins. The lobelias are producers of some potent chemicals that have historically been subject to diverse herbal remedies for maladies both real and imagined, syphilis is just one of them.

The lobelias are in the Bellflower Family Campanulaceae (campana means bell in Latin), named for the prevalence of radially or bilaterally symmetrical tubular bell-shaped flowers. With the exception of the bright red Cardinal flower (L. cardinalis), most range in color from lilac to blue.[1] Since the function of flowers is to attract mobile animals to sessile plants to transport male pollen from one to the female stigma in another, different colors and shapes can only have evolved for that purpose. Differences in color are especially noteworthy when two species in the same genus have a common origin and physiology but only differ markedly in hue. A vivid, eye-catching red was chosen for the color of the robes of the highest officials in the Roman Catholic Church below the pope who were cardinalis, Latin for principal. The name as color carried over to the bird and flower without ecclesiastical implications. The cardinal flower can only have evolved to attract a specific type of pollinator … perhaps a single species.  Lobelias with their drooping tubular bluish flowers are well suited for bee pollination. Bee vision extends through the blues to the ultraviolet range but they cannot see red. Cardinal flowers grow in boggy habitats in dense stands, evidence of multiple germinations at the same location. They are frequently attended by  butterflies flitting from flower to flower, especially spicebush swallowtails. It is quite probable that this has something to do with the color, which is attractive to butterflies while unseen by bees.

Cardinal flowers attract Spicebush Swallowtail butterflies

The purpose of sex is genetic diversity, a simple fact often misconstrued in the neo-culture of gender preference, both real and perceived. Nature goes to great lengths to ensure that genetic DNA is mixed and matched to produce the variation on which adaptability depends. The fossil record is a road map of what has and has not been able to change to meet new environmental challenges such as that induced by a meteor crashing into the earth near Chicxulub, Mexico 65 million years ago. Floral diversity can only be achieved via transport of male gametes from one plant to the female gamete of another. Dioecious species like maple and holly trees have a male plant and a female plant to promote diversity. Monoecious species like lobelias that have both sexes on the same plant are more common. Since the stamens of a flower that contain the male pollen are situated adjacent to or directly over the female pistil, self-pollination instead of the preferred cross-pollination would be the more likely outcome absent some evolutionary legerdemain. The term proterandrous, literally “before-male,” applies to lobelias. It means that a flower’s male pollen reaches sexual maturity before the female stigma is receptive. A pollinator would then be more likely to carry pollen from one flower with stigma deactivated to another that is receptive. Several days after opening, the stigma curls backward to come in contact with pollen dropped into the base of the flower from its own anthers. This functions as a backup, promoting self-pollination should pollinators fail to deliver. This then would assure survival although lacking the genetic diversification of DNA contributions from two different plants. [2]

In order to mature to reproductive age and produce seed for future generations, plants must survive to sexual maturity. Chewing insects and browsing herbivores must therefore be held at bay. This is the basis for spines and thorns that keep animals away but also for the chemistry of taste and aroma as deterrents. Plants evolve random mutations to create compounds against specific threats. The toxic “milk” in milkweed is exuded when the stem is punctured to keep sap-sucking bugs away. Some animals adapt to tolerate these toxins to employ them as their own deterrents. Monarch butterfly larvae that eat milkweed are a good example, as both the caterpillar and the adult gain the advantage of the plant’s poisons to escape predation. In a similar vein,  herbal medicine is the use of plant produced chemicals to promote human health. The difference is sentience … herbs are chosen for specific conditions based on human knowledge. Since the Great Lobelia is named L. siphilitica, syphilis provides a good case in point. The disease first appeared in Italy in 1494, infecting many of the French soldiers besieging Naples who spread it throughout Europe as “the French Disease.” The name syphilis comes from an epic poem attributing the disease to a shepherd named Syphilus who had offended the god Apollo. As punishment, “A hideous leprosy covers his body; fearful pains torture his limbs and banish sleep from his eyes.” [3] It was the scourge of Europe in the 18th and 19th centuries, infecting many notable composers, philosophers, and musicians including Mozart and Beethoven. [4]  

Syphilis is caused by Treponema pallidum, a spirochete closely related to the microbe that causes Lyme Disease which has similar symptoms. It is spread mostly through “intimate sexual contact,” the coarse vernacular now only too common. It was almost certainly imported from North America by lascivious Columbian mariners debarking in Italy. Bone samples that pre-date any association with Europeans confirmed that the disease occurred in Native American populations. The debilitating consequence of syphilis as it spread unchecked through the upper echelons of European society (one need not wonder why) precipitated a pressing need for treatment. Before the age of pharmaceutical drug trials, the only option was to identify a naturally occurring compound by trial and error; searching in North America where it started was the logical thing to do. Herbalists who had begun to study the unique flora of the New World in the eighteenth century working on occasion with Native Americans learned of a treatment for syphilis using lobelia plants. [5] By the time that Carolinus Linnaeas started cataloguing plants by genus and species in about 1735, the use of lobelia plants for treating syphilis had been well established ― enough to warrant assigning the scientific name Lobelia siphilitica. The fact that the treatment ultimately failed to cure the disease in Europe was attributed to deterioration of the relevant lobelia compounds on the long sea voyage. [6] It is much more likely that it didn’t do much good for the Native Americans either. 

The several species of flowers in the genus Lobelia were used for a wide variety of treatments by different tribal groups as a matter of local lore and cultural practice. The Iroquois, a confederation of six tribes in the northeast, used parts of the roots and stems of the cardinal flower for just about everything, considering it a panacea by itself but also as a complimentary adjuvant when mixed with other herbs. It was even taken for sickness (presumably depression) caused by grieving. The Cherokee, native to a vast territory comprising a large portion of the southeast, were more selective, using lobelia compounds for specific ailments like fever, rheumatism, and stomach problems. That they diagnosed and treated the disease called syphilis with lobelia is likely the fons et origio of its purported curative power. The Cherokee are also closely associated with a third species of lobelia called Indian Tobacco (L. inflata). The common name implies that it was used as a substitute for tobacco (genus Nicotiana from which nicotine is derived) which was widely used by native peoples throughout the Americas. According to the historical record, however, it was used as a substitute for tobacco in order to break the nicotine habit and not as an alternative. [7] There would be no need for a tobacco substitute as it was quite common. Indian tobacco was also used medicinally as a strong emetic, which is appropriate, since it has the highest concentration of the “medicinal” compound shared by all lobelias.

Indian Tobacco is medicinally the most potent of the lobelias

The efficacy of historic herbal remedies such as lobelia extracts can only be determined using science-based methods to distinguish snake oil from bonafide medicine. However, it is almost never cost effective to do so since human trials are exorbitantly expensive and wild plants are free. It is well established that the effective chemical in lobelia plants is an alkaloid named lobeline according to generic custom. It is similar in structure to nicotine, producing commensurate physiological effects. Lobelia extracts have been used in a variety of products like chewing gum and patches marketed to break the tobacco habit, emulating the Cherokee practice. In nineteenth century America, when treatment options were primarily limited to extracts from plants and animals, lobeline was one of the most popular. The common names gagroot and pukeweed suggest that it was often used as an emetic. This should not come as much of a surprise, because ingesting a poison is almost certain to induce the stomach to eject it along with everything else. There are anecdotal suggestions that death may have resulted from using lobelia as a home remedy. [8] Recent research has shown that herbal supplements, lobeline among them, can have adverse cardiovascular effects, particularly when used in combination with other drugs. [9]  While there has also been some research with animals to attempt to validate lobeline as a viable drug, the current consensus in the medical community is that “lobelia is not effective for smoking cessation, asthma, or any other medical condition..” [10] However, the jury is still out on lobeline, which has been shown to improve patient response to multi-drug resistance, a problem in chemotherapy.[11]  It is fair to conclude that Native Americans were onto something whose full potential has yet to be realized. Perhaps one might look to the Meskwaki Indians for inspiration. They used chopped up lobelia sprinkled in food or on beds of discordant couples as a means of easing marital discord. [12] It would likely not be too difficult to recruit drug trail participants for a love potion.


1. Niering, W. and Olmstead, N. National Audubon Society Field Guide to North American Flowers, Alfred A. Knopf, New York, 1998 pp 438-442

2. Gadella, T. W. “Campanulales” Encyclopedia Britannica, Macropedia William Benton Publisher, Chicago, 1974, Volume 3 pp 704-708.

3. Fracastor, Hieronymus, Syphilis, The Philmar Company, St. Louis, Missouri 1911. pp 1-58.

4. Franzen, C. “Syphilis in composers and musicians – Mozart, Beethoven, Paganini, Schubert, Schumann, Smetana”. European Journal of Clinical Microbiology & Infectious Diseases. 1 July 2008 Volume 27 No. 12 pp 1151–57.

5. Foster, S. and Duke, J. A Field Guide to Medicinal Plants and Herbs, Houghton Mifflin Company, Boston, 2000. pp 163-164.


7. Native American Ethnobotany Database at   

8. Foster, op cit.

9. Cohen, P. A.; Ernst, E. “Safety of herbal supplements: A guide for cardiologists”. Cardiovascular Therapeutics. August 2010 Volume 28 Number 4 pp  246 – 253.

10. Memorial Sloan Kettering Cancer Center.   

11. Ma Y. “Lobeline, a piperidine alkaloid from Lobelia can reverse P-gp dependent multidrug resistance in tumor cells”. Phytomedicine. 15 September 2008 Volume 15 No. 9 pp 754–758.

12. Harris, M. Botanica, North America, Harper Collins, New York, 2003, p 89.