This section is from the book "Materia Medica And Therapeutics - Vegetable Kingdom", by Charles D. F. Phillips. Also available from Amazon: Materia Medica And Therapeutics: Vegetable Kingdom.
Active Ingredients. - The active properties of lobelia are yielded both to alcohol and to ether, and appear to depend principally upon the presence of lobeline,1 a peculiar alkaline principle which presents itself in the form of a pale yellow liquid, of less specific gravity than water, upon the surface of which it floats. The odor is aromatic; the taste is pungent. It is soluble in water, more readily so in alcohol and in ether; and forms crystalline salts with the mineral acids. Lobelia also contains lobelic acid, which is crystalline, and soluble in water, alcohol, and ether; also a volatile oil, to which the odor of the drug is due; and a resin of acrid taste.
Physiological Action. - In small doses, lobelia acts as a diaphoretic and expectorant, the latter property being manifested without involving the pain of coughing. In full medicinal doses, say twenty grains of the powder, it acts as a powerful nauseating emetic, causing speedy and violent vomiting, attended by distressing and persistent nausea, and sometimes by purging, copious sweating, and great general relaxation. These symptoms are usually preceded by giddiness, headache, and general rigors. The effects produced are thus very similar to those of tobacco, only that for their occurrence larger doses are required. All experiments, alike upon men and animals, show that violent emesis and prostration ensue upon the administration of moderately large doses. A single grain, administered to a cat, induced these results in less than two minutes, the creature recovering in about three hours. Administered by the rectum, it produces the same distressing symptoms - sickness, profuse perspiration, and universal relaxation - which ensue upon a corresponding use of tobacco.
1 Discovered by Bastick and Proctor. See "Journ. Pharmaceut. Trans.," vol. x.
In excessive doses, or in full medicinal doses, too frequently repeated, the effects of lobelia are those of a powerful acro-narcotic poison. Extreme prostration is first induced, then great anxiety and distress, followed by convulsions and death. These symptoms are produced also by the alkaloid. The earliest effects are pain in the back of the head, with a feeling of fulness, tightness, and giddiness; these are followed by general tremor, with prickling sensation throughout the body, nausea, and profuse perspiration. Violent emesis, if not already present, soon ensues.
The painfulness and giddiness in the head generally alternate with the nausea; and, on the occurrence of profuse diaphoresis, the head-symptoms generally subside. Great prostration of strength and relaxation of the entire muscular system now set in, accompanied by heavy despondency and fear of death. There is much thirst; the hands and arms are thrown about, and the sufferer rubs or beats his stomach; the secretion of saliva and of mucus is increased; there is dryness, burning, and rawness in the throat, and frequent and difficult deglutition, with irritation of the oesophagus, and oppression of the praecordium. Extreme spasmodic difficulty of breathing attends these distressing conditions, and there is great flatulent distention throughout the abdomen, especially in the neighborhood of the navel, with frequent eructations, and flatulent discharges from the bowels.
At the same time the urine is very profuse, and causes a smarting sensation along its passage. Most other secretions are likewise increased. The pulse is irregular, slow, and feeble; or regular, slow, and full.
Before profuse perspiration sets in, there is generally a feeling of great restlessness, with distention of the abdomen, and irregular and spasmodic respiration.
The cheeks are usually suffused; the pupils are dilated, and the eyes become more brilliant. The senses are rendered more acute; the brain is generally excited; the mind wanders, sometimes lapsing even to wild and furious delirium, although a calm and placid sensation pervades the system generally.
The evacuations of the bowels are seldom increased in frequency. The patient mostly remains quite still, since to move causes return of the sudden and violent vomiting, with additional prostration. After a time he gets short periods of sleep, or sinks into a semi-somnolent condition, and out of one of these sleeps he awakes quite well.
When lobelia does not cause vomiting, its power is expended in profuse diaphoresis or diuresis.
When the dose is extreme, excessive prostration, anxiety, contracted pupils, insensibility, and convulsions set in, followed by death.
("In 1809 Samuel Thompson was indicted in Massachusetts for the wilful murder of Ezra Lovett, Jr., by giving him a poison called lobelia, on the ninth of January, of which he died the next day."1 The founder of
1 Barton: Vegetable Materia Medica, Phil, 1817.
Thompsonianism escaped conviction on the ground that he destroyed life through ignorance and not by design. If the State laws had declared that the wilful administration of powerful drugs by ignorant persons was a grave criminal offence, and had provided appropriate punishment, it is probable that the almost incalculable damage effected by this agent in the hands of Thompson's followers in New England and in this State would have been avoided. On the contrary, much of our medical legislation has been directly protective of this class of persons, and encouraged an increase in their number.)
Therapeutic Action. - In the United States this powerful plant is considered the most active article of the materia medica. When Europeans made their first settlement in that part of the world it was found to be the medicine most regularly resorted to by the aborigines. For a long time, however, it was left in the hands of irregular practitioners, and was only introduced to the notice of the profession by the Rev. Dr. Cutler, of Massachusetts. It was introduced into English practice in the year 1829, by the late Dr. Reece, who published a treatise upon its "anti-asth-matical properties."
The principal value of lobelia, in cautious hands, appears to be that of an anti-spasmodic. In some cases it becomes a useful adjunct to diuretics.
Lobelia has been resorted to as a substitute for tobacco in cases of strangulated hernia, in which it has been employed in the form of enema.
Paroxysmal spasmodic asthma, with extreme oppression, striving to cough, with inability to do so, is relieved by lobelia. It also often mitigates dry cough, with continual tickling in the throat, such as hinders the patient from sleep.
But, in some instances, it has appeared to lose power by repetition; and in any case it should be administered in doses so small as not to cause either nausea or vomiting. If either of these results should ensue upon the administration, the giving of the medicine must be immediately suspended.
Other disorders of the organs of respiration, such as catarrhal asthma, croup, and whooping-cough, when treated with lobelia, though great expectations were once entertained of its utility, appear not to have given encouragement to persevere with it.1
As an emetic, lobelia is unfit for general use, the operation being much too distressing for the patient, and by no means free from danger.
Compared with nicotine, it is a less active principle, though it is to tobacco that the general properties of lobelia admit of being most nearly compared. The taste and the sensations excited in the throat are similar; and, in default of any exact chemical tests by which the presence of lobelia may be ascertained, these form, at all events, an approximate clue to it. The analogy between lobelia and tobacco was originally observed by the American practitioners, and was confirmed by Dr. Elliotson.
I agree with many authors in believing that the administration of lobelia is best confined to temperaments remarkable for predominance of the nervous element.
Preparations and Dose. - Acetum Lobelia, m x. - xxx. (.60
1 Dr. Ringer, however ("Handbook," p. 484), speaks very highly of its use in un-complicated whooping-cough, and in all purely spasmodic respiratory affections. He has observed a much greater tolerance of the drug in children than in adults.
- 2.); Tinct. Lobeliae, m x. - xxx. (.60 - 2.); Tinct. Lobeliae AEtherea (B. Ph.); m x. - xxx. (.60 - 2.).