Lobelia is a species of colorful, flowering plant that is commonly known by the popular botanical variety Lobelia inflata, or the nicknames Indian tobacco, Indian weed, puke weed, asthma weed, gagroot, and vomitwort. Historically, as its nicknames suggest, it has been a popular herb for the support of the respiratory system health and the removal of toxins from the body. Lobelia grew in popularity as a smoking cessation aid until 1993 when it was ruled that lobelia was not a substitute for nicotine and did little to help people stop smoking.
Today, lobelia remains popular among herbalists for its potential use for individuals with asthma, bronchitis, frequent coughing, and other respiratory ailments. It is also popular in gardens as the bright flowers add an extra splash of color. There is no right or wrong way to enjoy lobelia, but learning about its past and the research around it can help provide better context to its continued relevance in gardens and as a medicinal aid.
What is Lobelia?
Lobelia is a species of more than 250 large and small plants in the genus Lobeliaceae. At higher elevations it is more often shrubby, with tree-like qualities, which compares to the smaller variants of the plant found in damp pastures and other low lying areas. (1) Lobelia prefers warmer regions but can grow in most climates if planted at the right time of year. (2) Lobelia should be planted earlier in the year the further it is grown from the equator.
The more familiar flowering varieties of lobelia are up to 10 inches tall and are covered with neon-like blue flowers. The flowers can also be white, pink, purple, or violet. In all cases, flowers are bright and showy. Gardeners recommend planting them along the edges of pots and soil beds so that the flowers tumble outward to create a splash of decorative color. The plant is fast spreading, dense, and has a medium texture. It grows best in cool environments with direct sunlight but will need occasional shade in hotter climates.
If shopping for lobelia, look for the following varieties and color they produce.
- Blue Moon – Dark blue
- Cambridge Blue – Soft blue
- Crystal Palace – Bronze-green leaves and dark blue flowers
- Paper-Moon – White flowers
- Rosamaunde – Carmine red flowers and white eyes
- White Lady and Snowball – White flowers
- Blue Cascade, Fount, and Hamburgia – Blue flowers, and is most suitable for hanging baskets
- Sapphire – Purple flowers with a white eyes and also ideal for hanging baskets
Sow lobelia seeds outdoors or in planters indoors for later transplanting when the weather warms. (3) Moist, good quality soil that is kept warm will help the plant to flourish. It takes up to 2 weeks for the first sprouts to appear. If starting them indoors, let them grow to around 2 inches, then move them to the garden about 4 inches apart. During periods of high heat, water the plant frequently and continue pinching off wilting flowers to encourage new blooms. Add liquid fertilizer about once a month until the first frost when lobelia will start to die back. For winter maintenance, it is best to keep the central stem intact when cutting back dead growth. Mulching over the plant will provide additional protection from frost.
The use of lobelia as a respiratory aid goes back to indigenous cultures of the Americas that predate the settlement of European explorers. (4) The term “Indian tobacco” is attributed to Native Americans in North America who burned the dried leaves over burning coals and inhaled the vapors. This is said to have helped with wheezing, muscle spasms, and other respiratory problems. Similarly, lobelia teas and tinctures have been used to aid with asthma, coughing, and bronchial tube restrictions. Plasters and compresses made with lobelia plant parts were also applied directly to the chest with the hope of opening airways.
In the 19th century, physicians prescribed lobelia to induce vomiting and “remove toxins from the body,” which earned the plant the nickname “puke weed.” (5)
In the 20th century, scientists believed that lobeline has a similar physiological effect to nicotine, but without the addictive qualities. Smoking cessation products containing lobeline were sold until 1993 when the U.S. Food and Drug Administration ruled such products were ineffective and the marketing materials for these products were misleading. (6)
The use of any plant or carbon material used for the goal of reducing tobacco smoking frequency may be risky due to the increased chances of developing emphysema or other lung and throat disorders. According to the American Cancer Society, “smoke from all cigarettes, natural or otherwise, has many chemicals that can cause cancer (carcinogens) and toxins that come from burning the tobacco itself, including tar and carbon monoxide. Even herbal cigarettes with no tobacco give off tar, particulates, and carbon monoxide and are dangerous to your health.” (7)
Studies show that the potential medicinal benefits of lobeline are the result of the plant compound lobinaline. In lobelia extracts, lobinaline has been found to comprise around 70% of all constituents in the plant. (8) Lobelanine and lobelanidine are the other major chemical compounds that have been identified. Research shows that these chemicals help to support muscle relaxation, detoxification, perspiration, may help to loosen mucus in airways, and may provide temporary relief from occasional coughing and overworked lungs.
How Lobelia Works in the Respiratory System
Lobeline supports the respiratory system by stimulating pulmonary afferent nerves. These nerves signal the surrounding fibers to move at a relatively high velocity. They are common in the lungs and provide contractions that lead to coughing, the release of mucus, and are important to reflexes in the surrounding tissue. (9) Lobelia has been shown to stimulate these nerves in a relatively short period when administered orally in high doses or intravenously. In some cases, individuals may experience a choking sensation prior to the cough reflex and release of fluids present in the respiratory system.
Lobeline also works through the stimulation of J-receptors (juxtapulmonary capillary receptors), which support the cough reflex. Lobeline also helps to relax muscles around the airways by signaling to pressure receptors around blood vessels to relax. In therapy, lobeline is thought to be useful in helping to ease ailments that cause breathing restrictions or an increase of fluids in bronchial passages; however, human studies that fully validate these claims are limited. (10)
Lobeline may also help to regulate the release of catecholamines, a compound found in the adrenal glands that is partly responsible for adrenalin-like responses. It is suggested that lobelia may help to ease wheezing or other general respiratory challenges that result from psychological stress, anxiety, and nervous tension. (11)
Lobeline has been suggested to produce a nicotine-like effect in the body. (12) Some studies have indicated that lobeline inhibits the binding of nicotine in the brain, while at the same time providing the same behavioral benefits offered by nicotine. Research comparing the effects of lobeline and nicotine in the brain have not found them comparable, with only nicotine providing the desired behavioral changes. This indicates that using lobeline as a smoking cessation tool instead of nicotine is unlikely to produce the desired results.
Lobelia Dosage, Warnings, Interaction
There is no established safe dosage of lobelia. Supplements can contain dosage amounts ranging from under 100 mg to over 1,000 mg. Smoking cessation products that contained lobelia recommended up to 5 mg of lobelia administered up to twice daily. Consuming more than this amount may result in nausea or vomiting. Lobelia can also be found in herbal blends that do not disclose the precise ratio of each herb. Supplements may contain whole parts of the root, or leaves, and extracts from each of the plant parts.
Lobelia is considered safe and well tolerated by most individuals. There is insufficient data about side effects and possible drug interactions at different dosage levels. Some research suggests that it may interact with psychiatric medications, nicotine substitutes and anti-smoking medications, and tobacco products. (13) Lobelia may interact with other drugs or therapies, so if changes to health occur immediately contact a primary care physician. Pregnant women should not use lobelia, and it should never be given to children unless under the supervision of a primary care physician.
Risk to Pets
The varieties of the lobelia species that are known to be potentially fatal to pets includes cardinalis, inflata, and siphilitica. (14)(15) All lobelia species may pose a risk to pets and should not be consumed. After ingesting the plant, immediate side effect can include sudden vomiting, diarrhea, salivation, arrhythmia (irregular heart rate), and abdominal pain. A veterinary professional will provide suggestions for treatment, including fluid therapy to help flush out the compounds. If treatment doesn’t occur within a few hours, symptoms can progress in severity until death.
Lobelia is available in capsules, tinctures, liquids, tablets, herbal blends, and tea. Each supplement may contain one or more of the varieties of the lobelia species, which could affect the potential medicinal benefits an individual will experience. For best results, consult with a primary care physician before starting any supplement regimen, and follow the manufacturer dosing guidelines and warnings.
Shopping for Lobelia
The NHC.com store carries a wide variety of brands that are known to follow Good Manufacturing Practices, use third party testing for quality and purity, or use ingredients made or grown in the USA. Experience lobelia and see if it makes a difference in your life.