This plant contains as its active principle, hydrastin; berberin, canadin and hydrastinin are also present, the latter being a derivative of hydrastin. Hydrastin and hydrastinin cause vasoconstriction and a rise in blood pressure, due to stimulation of the vasomotor center and to a peripheral vasoconstricting action.

Hydrastin stimulates the medulla and cord resulting in increased respiration, rise of blood pressure, slowing of the pulse and convulsions. Symptoms of paralysis soon follow, associated with shallow respiration, quickened pulse and a fall in blood pressure, due to medullary depression and paralysis of the heart muscle. Hydrastin also stimulates the uterus and the peristaltic activity of the intestine.

The activity of Hydrastis is not at all due to hydrastin, which is an artificial substance, not naturally found in the plant. Hydrastinin does not affect the central nervous system, in so pronounced a manner as does hydrastin; but in large doses it may cause death from respiratory paralysis. Hydrastinin is a peripheral vasoconstrictor, possessing this property to a greater degree than does hydrastin. Unlike hydrastin, hydrastinin does not paralyze the heart.

Hydrastis affects the mucous membranes generally. Its first effect is to produce stimulation of the gastric functions, to which is added a general increased reflex excitability. This is followed by atonic, relaxed conditions of mucous surfaces, resulting in debility, general catarrhal discharges and a tendency to ulceration.

Therapeutics

Hydrastis canadensis: Here we have a remedy most valuable in catarrhal inflammations of the nasopharyngeal and gastrointestinal tracts. One strong, characteristic and guiding symptom is found in the tenacious, tough, yellowish nature of the discharges which are, in addition, sometimes bloody and usually thick.

With these conditions in mind, Hydrastis will be found useful in dull, frontal catarrhal headaches, with thick, stringy yellow, lumpy nasal and postnasal mucous discharge. Likewise is the remedy indicated in watery excoriating coryzas, with much rawness in the throat and chest, and frequent sneezing.

The eyes are inflamed, with similar thick yellow tenacious discharges; catarrhal ophthalmia or blepharitis will at times need this medicine; also otorrheas following middle ear inflammation.

Stomatitis in children or in nursing women, particularly when chlorate of potash or mercury has been used injudici ously, will need Hydrastis when the characteristic yellow, tenacious mucous discharge is present, together with foul odor to the breath and thickly coated yellow tongue, which often is flabby and swollen, taking the imprint of the teeth.

Small aphthae are found upon the buccal mucous membrane and small ulcers are frequently to be seen upon the tonsils and in the pharynx generally.

Constipation is a marked symptom of the Hydrastis patient, who has little or no desire for stool, but complains of a peculiar faint, empty or gone sensation at the pit of the stomach. The remedy is often useful under these circumstances and when purgatives have been abused. Gastroduo-denal catarrh, as well as chronic catarrhal enteritis, will need Hydrastis very frequently. The stools are bloody or at least blood-streaked and consist of the characteristic tenacious yellow mucus.

The later stage of gonorrhea will require Hydrastis when the discharge is sticky, yellowish and tenacious. The same description applies to the leucorrheas for which this remedy is indicated and in these cases, ulceration of the cervix uteri and of the vagina, will be present.

In the gastric or bilious complaints for which Hydrastis is serviceable, the tongue will be found coated yellow in the centre with red, clean edges.

An alkaloid of Hydrastis, hydrastini-mini muriaticum, when given in the sixth decimal trituration, is often of great value in controlling the hemorrhage of uterine fibroids.

Characteristic Symptoms Of Hydrastis Canadensis

1. In nasal catarrh, secretions more from posterior nares; thick tenacious; air feels cold in the nose.

2. Stomatitis in nursing women or weakly children, especially after mercury or chlorate of potash.

3. Faintness at stomach, sinking, gone feeling.

4. Gonorrhea, second stage, thick, yellow discharge.

5. Leucorrhea, tenacious, ropy, thick yellow.

6. All mucous secretions tenacious, thick, erosions of mucous surfaces.