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 ends of the young shoots and the leaves upon these parts have a bitter and nauseous taste, and, while fresh, yield a remarkable odor on being bruised. They contain two peculiar principles, one of which is neutral, the other a volatile liquid alkaloid. The neutral principle, called Scoparine, C21H12O10, forms yellow crystals, soluble in water and alcohol, and is destitute of bitterness. Dr. Stenhouse believes it to represent the diuretic property of broom-tops. The alkaloid, called Sparteine, C15H16N2, is pale when newly prepared, but on exposure becomes brownish, and has a bitter taste. It forms crystalline salts with bichloride of platinum, terchloride of gold, and corrosive sublimate, and is extremely poisonous, being little inferior in this respect to either conia or nicotia. Extractive matters and salts are likewise found on broom-tops, but they are of no importance.
Physiological Action. - Broom-tops have long been celebrated for their cathartic and diuretic powers, which are rendered available by infusion in water or in spirit. In small doses, the infusion is mildly laxative; in large ones it becomes emetic and purgative.
As already said, the diuretic effects of broom appear sufficiently accounted for by the ascertained powers of scoparine. The alkaloid sparteine is powerfully narcotic, but exists in such small proportions that it is not easy to judge whether it really takes any important part in the action of broom. Schroff killed a rabbit in six minutes with a single drop of sparteine which he placed in its mouth; there were violent tetanic symptoms. But Mitchell and Stenhouse gave four grains to a rabbit which lived for three hours afterward, and then died in stupor without convulsions. This difference of experimental results, and the fact that sparteine is little soluble in water, make it doubtful whether it goes for anything in the action of decoction of broom-tops.
Therapeutic Action. - Broom has been employed in dropsies, and with considerable success. Cullen says he found it more trustworthy than any other diuretic.
But the value of the medicine is dependent of course upon the particular character of the dropsical effusion. In acute inflammatory cases, and when the kidneys are diseased, the use of broom might prove objectionable; and in cases of thoracic dropsy it is expressly declared to be so, especially when the dropsy is accompanied by pulmonary congestion, in which there is inflammation of the lungs, however trifling. In cardiac dropsies, on the other hand, broom is most useful. Whenever employed, diluents should also be freely used, with a view to assisting the action of the medicine. Cullen recommended that half an ounce of the fresh tops should be boiled in a pint of water until reduced to one-half that quantity, two tablespoonfuls of this decoction to be given every hour, until the whole had been taken, or, at all events, until the bowels were moved.
Preparations and Dose. - Infus. Scoparii (B. Ph.),
(30. - 90.); Succus Scoparii (B. Ph.), 3 j. - iij. (4. - 12.).