Botanical Name: Lobelia inflata, Campanulaceae

Common names: Lobelia, Indian tobacco, Wild tobacco, Puke weed, Bladderpod

Similar species: L. cardinalis, L. fenestralis, L. kalmii, L. dortmanna, L. laxiflora, L. puberula, L. siphilitica (pictured)

Plant description: Erect annual or biennial herb, 15 cm to one meter in height. Stem is angular and very hairy, yellowish-green in colour. The leaves are alternate, scattered, sessile, oblong, serrate and hairy, with distinct veins. The flowers are small, numerous, pale-blue, on short peduncles, each originating from the axil of a small leaf. The calyx consists of 5 subulate segments. The corolla is tubular, small, slit on the upper side, ventricose at the base; the limb bilabiate; tube prismatic; segments spreading, acute; two upper ones lanceolate, three lower ones oval. The anthers are united into an oblong, curved body, and of a purple color; filaments white. Style filiform; stigma curved, 2-lobed, enclosed by the anthers. The capsule is 2-celled, ovoid, inflated, striated, 10-angled, crowned with the persistent calyx. The seeds  are numerous, small, oblong, and brown. When broken or cut, the fresh plant exudes an acrid, milky juice that tastes almost like  tobacco. The dried herb has a faint odour, but when chewed produces a strong, acrid taste, affecting the pharynx and promoting nausea.

Habitat, ecology and distribution: Lobelia inflata is found primarily in the eastern United States and Canada, thriving in dry soil along roadsides, in dry fields, and old pastures, as well as in woodland grazing areas. Most species flower from July to September, or until the first frost.

Part used: Although the whole plant is medicinal, the leaves and seeds are more often used. Dr. W.H. Cook considered the seeds twice as strong as the leaf. The root is considered to be much more active, and is not typically used.

Harvesting and collection: Lobelia is typically gathered in the last week of July through to the middle of October. As the season progresses the number of seed pods increases from successive flowerings. King’s American Dispensatory (1893) recommends that the plant should be dried in the shade, and then covered if it is to be reduced to powder. The seeds can be separated out by thrashing.

History: Although claimed by Samuel Thomson as his own discovery, King’s American Dispensatory (1893) mentions that Lobelia inflata was used extensively as a medicinal prior to Thomson, by First Nations groups such as the Penobscot and Wampanoag, and possibly by later European settlers in the area. Besides Lobelia inflata, which is officinal for this species, other species, including L. cardinalis and L. siphilitica are mentioned in the ethnobotanical literature. Lobelia cardinalis was used by the Cherokee First Nations for a wide variety of disorders: as a poultice of crushed leaves used for headache and pain, as an infusion of root taken for indigestion and parasites, and as a cold infusion of the leaves that was “snuffed” for nosebleed, or given internally in the treatment of rheumatism, colds, croup, fevers, and ulcers (Hamel and Chiltoskey 1975, 28). L. syphilitica, as its name suggests, is reported to been of use in the treatment of syphilis, as well as other disorders. Without a doubt Lobelia is among the most famous plants native to North America, having secured for itself a permanent, if not notorious reputation in the annals of medical history. Although Lobelia was used and known to many First Nations peoples prior, it is Samuel Thomson that introduced it to a burgeoning U.S. population. In his early years as a healer, and as his reputation grew, the usage of Lobelia became vilified by Thomson’s medical opponents. In 1809 Thomson was arrested, charged with murder by a Dr. French, who accused Thomson of killing a young man with Lobelia. Thomson endured a bitter, cold winter in a dank, unheated jail cell, nearly killing him, before his trial was heard later the next year. At the trial Thomson was thoroughly vindicated, and in a surprising turn of events Dr. French withdrew the charges. Nonetheless, as Thomson’s reputation grew so did the chorus of opposition from the licensed medical doctors, and in his American Medical Botany (1817-20) Dr. Joseph Bigelow stated that Thomson had killed the patient with Lobelia, and since then, this error has been repeated countless times. In a later case, a Thomsonian physician named Frost was found guilty of murder in the fourth degree for administering Lobelia as a poison, but was sentenced for only three months. The medical use of Lobelia was first reported by Dr. Manasseh Cutler in the treatment of asthma, who learned of its virtues from  Thomson. The genus name Lobelia was given in honor of Matthias de Lobel (de l’Obel), a distinguished botanist of the sixteenth century. The species name inflata is to describe the mature, inflated seed pods.

Constituents: Lobelia contains about 0.24-0.48% piperidine alkaloids, of which lobeline is considered the major, but includes other less-known alkaloids such as lobelanine, lobelanidine, norlobelanine, lelobanidine, norlelobanidine, norlobelanidine, and lobinine (Newall 1996, 187, Evans 1989, 575). Other constituents include a bitter glycoside called lobelacrin, chelidonic acid, fats, gum, resin and volatile oil (Newall 1996, 187). King’s American Dispensatory (1893) states that “the active principle of lobelia is an acrid, irritating, unstable alkaloid, called lobeline, first obtained by Wm. Procter, Jr. (Amer. Jour. Pharm., 1838, p. 98, and 1841, p. 1), as a yellowish liquid of faintly aromatic taste, soluble in water and exhibiting an alkaline reaction… Lobeline and its salts are exceedingly active emetics. Though stable when thus combined, it readily decomposes when freed from contact with the other constituents of the plant. Heat applied to either an aqueous preparation or an alcoholic tincture of lobelia, destroys this alkaloid, hence a decoction or hot infusion of this plant is irrational.”

Medical research:
• Central Nervous System: The alkaloid lobeline has long been thought to have peripheral and central effects upon the central nervous system similar to but weaker than to nicotine (Newall et al 1996, 187; Bradley 1992, 149). Thus, ever since lobeline and its effects were identified in the 19th century, the herb Lobelia has been used to treat tobacco addiction. Recent research has shown that although the effects of lobeline are 10 times less potent than nicotine, the anxiolytic effect is identical (McCurdy et al 2000). Unlike nicotine, lobeline does not increase the number of nicotinic receptors with chronic administration (McCurdy et al 2000), and has been shown to affect nicotine administration by down-regulating nicotine-evoked dopamine release (Dwoskin and Crooks 2002). Lobeline appears to act by both promoting the release of dopamine from the storage vesicles within the presynaptic terminal, while inhibiting dopamine uptake (Dwoskin and Crooks 2002). Some researchers have postulated that lobeline may interact with a different subtype of central nicotinic receptors than nicotine, or functions through non-nicotinic mechanisms (Dwoskin and Crooks 2002). Lobelia may also hold promise for other addiction disorders as it has also been shown to antagonize methamphetamine-induced dopamine release, in vitro (Dwoskin and Crooks 2002).
• Gastrointestinal: Lobeline is thought to account for Lobelia’s emetic properties (Newall et al 1996, 187).
• Respiratory: At therapeutic doses the alkaloid lobeline has been shown to act upon the chemoreceptors of the glomus caroticus, promoting a reflex response of the respiratory center (Bradley 1992, 149).

Toxicity: Duke lists the LD50 of intraperitoneal injections of lobeline in experimental animals to be 39.9 mg/kg (Duke 1985, 536), which unfortunately, says nothing of the potential toxicity of the oral usage of Lobelia. Although the purified alkaloid lobeline is certainly toxic, how this translates to the oral use of the whole herb is a controversial issue. Herbal practitioners have long observed that it is impossible to achieve a fatally toxic dose of lobeline from Lobelia herb as vomiting will be induced. Lobeline itself appears to be at least partially responsible for this property of Lobelia. Despite close to 200 years of popular use, the number of adverse effects reported for Lobelia is remarkably low, and even then, some of the accounts are vague, historical inaccuracies. Caution is still warranted however, as herbalists such as Michael Moore cites personal observations of Lobelia’s potential toxicity (1979, 98).

Herbal action: emetic, cathartic, diaphoretic, expectorant, antispasmodic, anticonvulsant, nervine, sialagogue, sedative, counter-irritant

Indications: fever, colds, cough, bronchial asthma, chronic bronchitis, sore throat, laryngitis, measles, pneumonia,muscle spasm, neuralgia, sprains, convulsion, epilepsy, eclampsia, rigid os uteri, indigestion, dyspepsia, headache, constipation, intestinal spasm, fecal impaction, cardiac angina, cardiac congestion, high blood pressure, dermatitis, eczema

Contraindications and cautions: extreme nervousness, shock, weakness, fatigue, pregnancy

Medicinal uses: King’s American Dispensatory (1893) states that when the fresh herb is chewed it stimulates a pronounced release of saliva and mucus into the mouth and pharynx, accompanied by a burning, acrid taste and a feeling of nausea. If consumed in sufficient volume, Lobelia will induce vomiting, causing the stomach to eject its contents along with large amounts of gastric mucus. This emetic response is accompanied by symptoms such as profuse perspiration, lethargy, and muscular relaxation. King’s American Dispensatory (1893) states that these symptoms soon dissipate however, and what typically remains is a sense of bodily satisfaction. King’s adds that if the emetic properties are not induced, a course of Lobelia will cause the bowels to purge. As the inspiration of his system of medicine, Thomson believed that the medicinal actions of Lobelia upheld and promoted the fundamental basis of health and well-being. Essentially, Lobelia achieves this by removing any obstruction to the vital force, wherever it occurs. How it does this is through three primary modes of action:

  1. Lobelila is a powerful gastric stimulant, and when used to the point of emesis, stimulates a non-specific immunological response (i.e. vomiting, glandular secretions). This in turn, has a reflex activity upon other metabolic processes, speeding the up the breakdown and processing of cellular wastes. The use of Lobelia as an emetic, along with sweating therapies, was the foundation of Thomson’s system of herbal medicine. Although such treatments were generally out of favour in North America by the turn of the 20th century, both the ancient medical system of Ayurveda and Chinese medicine maintain emetic therapies as a specialized practice.
  2. Lobelia is a diffusive remedy, promoting the movement of blood and fluids to the periphery, where toxins are eliminated through the skin as perspiration. This model is based in Thomson’s belief that the vitality of the body was synonymous with the function of stomach, in much the same way that the hearth was at one time the center of the home. Thus the vital function was in actual fact the ‘heat’ of digestion, that burns and cooks the food within it. By stimulating this fire, causing it to radiate outwards to the periphery of the body, the coldness and obstruction of disease is removed.
  3. Lobelia is antispasmodic, relaxing areas of contraction, thereby improving the movement of blood and fluids in and out of tissues. By relieving the contracted response of obstructed and diseased tissues or organs, Lobelia allows the vital energy to permeate, facilitating natural eliminative processes.

The pulse of Lobelia is “full, labored, and doughy,” indicating obstruction and congestion, but with a significant amount of energy behind it. Lobelia does not work  without the help of the vital force: it merely harnesses the vital reserve to remove the obstruction. In patients with thin and weak pulses Lobelia may be too powerful, and caution should be exerted. Looking at the tongue, Lobelia is indicated where a thick coating covers its base. The first and primary indication for Lobelia is as a diaphoretic and diffusive stimulant in the treatment of fever. Used in larger, emetic doses along with steam baths and other herbs such as Cayenne and Bayberry, Lobelia was believed by Thomson to be able to overcome almost any obstruction to the vital force. In his Narrative, Thomson recounts his success with typhoid and yellow fever, at a time when those under medical care were dying in great numbers, not by inhibiting thermotaxis, but by removing the obstruction and allowing the condition to resolve naturally. Lobelia helps to ripen a fever. Similarly, Lobelia is used when normally eruptive diseases like measles and scarlet fever fail to mature. Lobelia is indicated in any kind of chest pain, especially that of a heavy and oppressive nature. Generally, Lobelia relieves chest congestion and initiates thoracic relaxation. For lung congestion and spasm Lobelia dilates and relaxes the bronchus and bronchioles, promoting the expectoration of mucus. Lobelia is thus indicated in a variety of lung complaints, including asthma, bronchitis, croup, and whooping cough. Lobelia also acts upon the heart, relaxing and decongesting the tissues, making it a specific for angina and cardiac congestion, with shortness of breath and a painful, bruised feeling in the chest. Due to its relaxing nature, Lobelia is indicated in almost any spasmodic affliction. King’s American Dispensatory (1893) states however that in order for Lobelia to control spasm, the dose must promote a nauseant or emetic effect. Such doses are used to treat tetanus, chorea, infantile convulsions and other convulsive disorders such as epilepsy. This powerful antispasmodic activity also commends itself to obstetrics. Lobelia is mentioned in King’s as being very helpful “…to overcome a rigid os uteri during parturition,” while at the same time, “…relaxing the perineal  tissues” prior to delivery. In the digestive tract Lobelia is a powerful agent to relieve intestinal obstruction and spasm, used in fecal impaction “…when cathartics would result fatally.” To achieve any of these effects Lobelia was typically administered in physiologic doses by mouth and rectum. Dr. W.H. Cook suggests that the use of mint or burdock seed can help to alleviate the nausea of physiologic doses of Lobelia. Used in small doses, Lobelia is a stimulant to digestive function, overcoming atonic states of the bowel, as well as treating indigestion and  yspepsia, being especially indicated in the nausea and sick headache that can accompany such conditions. Lobelia was also used at one time  in a wide variety of skin disorders, including herpes, erysipelas, eczema, and psoriasis, as well as an antidote to Stinging Nettle and Poison Ivy. The affected area was bathed frequently in a aqueous solution, and used as a fomentation. Prepared as a poultice with an excipient such as slippery elm, Lobelia was valued by both the Eclectic and Physiomedicalists to ease the discomfort of insect stings. An aqueous extract was also used in ophthalmic disorders as an eye-wash. For earaches, John Christopher recommends that Lobelia can be instilled into the ear as a medicated oil.

Pharmacy and dosage: King’s American Dispensatory (1893) notes that hot water, vinegar, and alcohol are all useful methods of extraction, but that boiling dissipates Lobelia’s  properties. For non-emetic purposes Lobelia is usually taken as a tincture, in small doses. To achieve an emetic result, give the extract in small frequent doses until nausea is induced, and then larger doses until emesis. Emesis is facilitated by having the patient drink several glasses of water before and during treatment. Lobelia tincture and medicated oil can also be used topically, as needed.

Dosages for Lobelia have wide variance within herbal medicine, depending not only on the condition, but as well to the particular ethic of the practitioner. On the one hand there are those who have rational concerns about the potential toxicity of Lobelia in large, emetic doses. On the other hand almost all of the historical and anecdotal evidence seems to support its usage as an emetic, in the treatment of both acute and chronic conditions.

Because there is this wide variance in traditional dosages, each practitioner will have to decide for themselves what is and what is not appropriate. For example, many practitioners have used Lobelia in formulation or in relatively small doses to treat spasm without initiating an emetic reflex or nausea. Certainly our objective is to cause the patient the least amount of discomfort as possible. Nonetheless, we should not forget the justifiable and natural discomfort that can result when a positive eliminative process overcomes an obstruction. If the indications for using Lobelia can be identified correctly, then the weight of close to 200 years of empirical usage will lend itself to the practitioner’s advantage.

Fresh Plant Tincture (aerial parts): 1:2, 95% alcohol, 3-10 gtt. • Dry Plant Tincture (aerial parts): 1:5, 50% alcohol, 3-20 gtt. • Acetum Tincture (aerial parts): 1:5, 50% vinegar, 10-20 gtt. • Seed Tincture (seed): 1:5, 65% alcohol, 3-10 drops • Cold Infusion (dried herb): 2 – 5 g in 250 mL water • Powder (aerial parts): 200 – 600 mg • Medicated oil (dried ground seeds): grind seeds and use ethanol as an intermediate solvent, and prepare as 1:7. Apply topically as needed.

Enema: powders of Lobelia 1., Nepeta (Catnip) 2, Zingiber (Ginger root) 1, Pinus canadensis (Pine bark) 2. Infuse 10 g of powder in one litre of cool water, overnight.


Compound Tincture of Lobelia (King’s American Dispensatory, 1898): take 30 g, coarsely powdered, each of Lobelia  herb, Sanguinaria root (Bloodroot), Lysichiton root (or Dracontium, Skunk-cabbage root),  sarum root (Wild Ginger root), and Asclepius root (Pleurisy root). Macerate or percolate with two litres of  iluted alcohol. Used in the treatment of croup, whooping-cough, bronchitis, asthma, convulsions, and in all cases where an emetic is required, in both children and adults. Adult dose is 5 – 10 mL, up to five times daily.

Compound Tincture of Lobelia and Capsicum (King’s American Dispensatory, 1898): take 60 g, coarsely powdered, each of Lobelia herb, Capsicum pods (Cayenne), and Lysichiton root (or Dracontium, Skunk- cabbage root), and macerate or percolate with one litre of diluted alcohol. Used in the treatment of cramps, spasms, convulsions, and tetanus. Adult dose is 2.5 – 5 mL, every 10 or 20 minutes, as often as the urgency of the case requires. • Antispasmodic Tincture (W.H. Cook): “Lobelia seeds and capsicum, each half an ounce; cypripedium, two drachms.  Tincture with eight ounces of the Compound Tincture of Myrrh. It may be used in doses of a teaspoonful, or much more, in water or some demulcent infusion, when vomiting is required under circumstances of depression–as in narcotic poisoning, apoplexy from over-eating, membranous croup when lobelia alone will make no impression, etc. It is to be given at short intervals, so as to obtain very prompt action. In sudden depression of the pulse, all forms of collapse, and shock of injury, it is unequaled as a stimulant; and may be given in doses ranging  from a few drops to one or two teaspoonsful, every five or ten minutes, till reaction is obtained.”

Antispasmodic Tincture (John Christopher, 1976): equal parts Lobelia seed, Scutellaria (Skullcap) herb, Lysichiton  root (or Dracontium, Skunk-cabbage root), Commiphora gum (Myrrh), and Actaea (Black Cohosh), and one half part Capsicum pods (Cayenne). Listed by Christopher in the treatment of epilepsy,  convulsions, lockjaw, tetanus, tremors, fainting, hysteria, cramps and coma. Dose is one drop to several drops.