Syn.—Lobelia; Indian Tobacco; Vomit Weed.
P. E.—Whole plant.
N. H.—North America.
Properties: Sedative, antispasmodic, emetic.
Physiological action: In large, poisonous doses lobelia is a powerful depressant, causing extreme prostration and relaxation. Rapid and feeble pulse, burning in the throat and stomach; nausea, vomiting, purging, general gastric distress; cold, clammy skin, tremor, shallow respiration, feeble heart's action, anxiety, muscular relaxation, sweating, great debility, convulsions, coma and death resulting from paralysis of the pneumo-gastric nerve; the action of the heart continuing after the former has ceased. In large but not toxic doses it will cause headache, dizziness, nausea and vomiting. In small doses it is a stimulant, acting especially on the nerves that control secretion and digestion. It acts on the involuntary muscles first, then on the voluntary; impaired circulation, slow pulse result. It is of value on account of its stimulating effect on the nervous system, showing its power over the sympathetic nervous system. It is a local, irritant, but will not produce inflammation., Has a decided action on the nervous system and particularly on the centers of the pneumo-gastric nerve.
Indications: Full oppressed pulse; difficult, irritable, spasmodic, oppressed breathing. Respiratory disorders resulting from nerve irritation or exalted nerve force. A feeling of oppression in the chest with difficult respiration. In pains of agonizing character if otherwise indicated.
Use: Lobelia is a nerve depressant of great power, therefore should not be used when the pulse is very feeble. As a relaxant it is superior to most other remedies. In minute doses it checks vomiting. In small doses it is a stimulant; in large doses a relaxant and depressant to the nervous system, while in very large doses it is a prompt but depressing emetic. We think of it in threatened spasms with exalted nerve action, spasms of children, spasmodic asthma, spasmodic and membranous croup, pneumonia, coughs and colds. Applied locally to a felon before suppuration has set in it may abort it. In rhus tox poisoning 2 drachms to 4 ounces of water applied locally is very good treatment. A single large dose will relieve angina pectoris but should not be given where there is marked feebleness. In the obstetrical practice when os is doughy and unyielding it is of value. The average dose in coughs, colds and pneumonia is about 10 to 40 drops to 4 ounces menstruum, teaspoonful every 1 to 3 hours. In these cases it should always be combined with 10 to 20 drops of sanguinaria, which makes it more effective and less depressing. In croup and membranous croup it should be used in larger doses, especially in the latter. In these cases it is best to combine with sanguinaria to make it more effective. In spasmodic asthma, spasms, angina pectoris is should be used in much larger doses. In minute doses of 3 to 5 drops in 4 oz's of water, teaspoonful every 3 to 4 hours it is a good stimulant. In these minute doses, in proportionally less quantity according to the age of the child, it is useful in infantile colic.
The Materia Medica and Clinical Therapeutics, 1905, was written by Fred J. Petersen, M.D.