Herbal Nerd Society Exclusive Article
Lobelia (Lobelia inflata) was a favorite herb of the Eclectic (Thompsonian) herbalists from the 1800s. It was used primarily as an emetic to purge toxins and a relaxant for respiratory concerns. There are 415 different lobelia species and all have some amount of lobeline. Some are used medicinally. Some are not. It is only one of the alkaloids in lobelia but it is the most reactive medicinally. The primary constituent that has gained the lion’s share of research from chemists which serves this purpose is lobeline.
The molecular formula for lobeline is C22H27NO2 but it has a variety of other chemical names even though formula is unchanged. Synonyms include lobelin, (-)-lobeline; lobeline hydrochloride; Alpha-lobeline; 8,10-diphenyllobelionol and others depending on the context. Lobeline is considered a “true” alkaloid due to the existence of the nitrogen ring in the center of the formula. Like other alkaloids, lobeline impacts the central nervous system. Depending on the dose or use, it can either serve as a relaxant or a stimulant. The taste, like other alkaloids, is also quite bitter.
Lobeline is the subject of many studies due to it’s ability to bind to the nicotine receptors in the brain known as striatum. This is the section of the central nervous system that control impulses and rewards. Tobacco contains nicotine (another alkaloid) which binds to the alpha4-beta2 receptor and plays a key role in tobacco addiction. The replacement of lobelia in smoking mixtures are part of smoking cessation programs known as Competition Neuronal Nicotinic Receptor Antagonist Therapy. Put simply, it offers substitute chemicals in the form of whole plants or isolated constituents from these plants to fill the craving of nicotine while reducing the dependency on the alkaloids in question.
Lobelia inflata has many uses. It has been used to address respiratory disorders, peripheral vascular disorders and insomnia along with the standard use for smoking cessation. Taken internally in amounts higher that 10-20 drops (5-10 ml) per liquid extract dose, it can activate the nicotinic receptors at autonomic ganglia and induce vomiting thus supporting the Eclectic physicians traditional use as an emetic. This is why lobelia has earned the title of a “low dose botanical”. It is always advised to start with a low dose, 1 or 2 drops and add a few more after a few hours to gauge the effect on the patient. Stop the dose increase at the first signs of nausea or undesired increased heart rate. Results will vary upon the person.
As an antispasmodic, lobelia is remarkable. Herbalist 7Song keeps a tincture of lobelia in his first aid kit to reduce spasms caused by asthma among other conditions. The lobeline in this plant can be used to reduce muscle or internal organ spasms simply by adding a few drops of lobelia tincture to an existing formula or by adding a pinch of dried lobelia to a tea blend.
Counter-Indications for Lobeline
Lobeline inhibits dopamine release and is counter-indicated for conditions such as Parkinson’s Disease that include an already low amount of dopamine. It is counter-indicated with medication that reduces dopamine such as medication for ADHD and schizophrenia although there is no research at the time of this writing to back up this caution. Lobelia increases blood pressure in some doses and is thus counter-indicated for those with hypertension. Do not take lobeline containing herbs if you are pregnant or breast feeding without first consulting with a qualified healthcare practitioner.
In 1985, the FDA declared Lobelia inflata a poisonous plant after comparing it to a different lobelia species (Lobelia berlandierri) which is toxic to rats. It remains on the Poisonous Plant Database despite the fact that lobeline is now used in the pharmaceutical industry.
Further Research
Dr. Christopher’s Herbal Legacy – Lobelia Counter-Indications
NCBI – The Role of Striatum in Social Behavior