Derivation.—Aconite is obtained from the root of aconitum napellus, which grows in Northwestern North America, Europe and Asia in mountainous regions, and cultivated in the United States for its beautiful flowers.

Properties.—The fresh leaves have a faint narcotic odor, most sensible when they are rubbed. Their taste is at first bitterish and herbaceous, afterwards burning and acrid, with a feeling of numbness and tingling on the inside of the lips, tongue and fauces, which is very durable, lasting sometimes many hours. When long chewed they inflame the tongue. The dried leaves have a similar taste, but the acrid impression commences later. Their sensible properties and medical activity are impaired by long keeping. They should be of a green color, and free from mustiness. The root has a feeble earthy odor. Though sweetish at first, it has afterwards the same effect as the leaves upon the mouth and fauces. It shrinks much in drying and becomes darker, but does not lose its acrimony. Those parcels, whether of leaves or roots, should always be rejected which are destitute of this property. Aconite root is officially described as being “slenderly conical, 4 to 10 cm. long, 10 to 20 mm. thick at the crown; occasionally split; longitudinally wrinkled; dark brown and marked with coarse whitish root-scars; fracture short, horny or mealy; internally whitish or light brown; the cambium zone irregular and 5 to 7-angled; odor very slight; taste sweetish, soon becoming acrid and developing a tingling sensation, followed by numbness.”

Preparations of the leaves are not official in the U. S. P. The root is five times stronger than the leaves.

Constituents.—The alkaloid representing the action of the drug is aconitine, which is precipitated by ammonia from an aqueous solution of an alcoholic extract of the root of various species. It is a colorless, crystalline or amorphous, gray powder, almost insoluble in water, and soluble in 22 parts of alcohol, in 44 parts of ether and 1 part of chloroform. Its salts are soluble in water. Aconitine or its solutions, unless very dilute, are too poisonous to be tasted.

Commercial preparations vary in purity and strength, and since it is extremely poisonous its internal administration is undesirable. Pseudo-aconitine, aconitine and other alkaloids in combination with aconitic acid have been obtained from aconite, but their identity and chemistry are uncertain.

Dose.—Horses and cattle, 3 to 20 grs.; sheep and pigs, 1 to 3 grs.; dogs, ¹/₁₀ to ¹/₁₁ gr.

PREPARATIONS

FLUIDEXTRACTUM ACONITI—FLUIDEXTRACT OF ACONITE

Made by maceration and percolation with alcohol and water and evaporation. Assayed so that each 100 c. c. contains 0.4 gm. aconitine.

Dose.—Horses and cattle, 5 to 20 m.; sheep and pigs. 2 to 5 m.; dogs, ¹/₁₀ to 1 m.

TINCTURA ACONITI—TINCTURE ACONITE

Made by maceration and percolation of aconite, 100; with alcohol and water to make 1000.

Dose.—Horses and cattle, 20 m. to 1 dr.; sheep and pigs, 10 to 20 m.; dogs, 2 to 10 m.

Fleming’s Tincture (non-official) (79 per cent).

Dose.—Horses and cattle, 8 to 20 m.; dogs, ¹/₂ to 2 m.

ACONITINA—ACONITINE

Not used to any extent in veterinary practice; is very unreliable and varying in strength. Aconitine often contains a considerable proportion of aconite and benzaconine, and so varies in activity, which is a great objection to the use of one of the most powerful drugs known.

Dose.—Horses and cattle, ¹/₃₀ to ¹/₅ gr.; dogs, ¹/₂₀₀ to ¹/₁₀₀ gr. subcutaneously.

Actions of aconite, its preparations and derivative are anodynes and sedatives, acting specially on the peripheral endings of the sensory nerves, on the heart and on respiration. Aconite kills by respiratory arrest.

Its physiological actions as a cardiac and respiratory sedative renders it a febrifuge; it is also diaphoretic and diuretic. It is prescribed in acute febrile conditions, and in the earlier stages of acute local inflammation. It is used topically to relieve pain.

General Actions.—Locally applied, in virtue of its action on sensory nerves, aconite produces first irritation, tingling and twitching and subsequently numbness and anesthesia. The tincture of aconite is rapidly absorbed and quickly passed into the tissues, as is shown by the blood of a poisoned dog five minutes after the drug has been administered, being transferred into the veins of another dog without producing the physiological action of the poison.

Toxic Effects.—One and one-half drachm of the tincture (equal to about one drachm of aconite root) is given as the minimum fatal dose for the horse, one-half drachm will occasionally cause very serious symptoms and where an idiosyncrasy exists as little as fifteen minims will cause toxic symptoms.

It causes great muscular weakness, dimness of sight; pupil at first may be dilated or contracted, but as the end approaches remains dilated; shallow irregular and labored respiration, a slow and small pulse, becoming rapid and imperceptible near the end. Gulping, frothy saliva, flatulence, belching, retching, nausea, etc. There is often a peculiar clicking sound made from the constant attempts at swallowing.

Coldness of surface, clammy sweat, anxious countenance, extreme weakness of the extremities, lowering of temperature 2 to 3 degrees, abolishment of sensation, reflexes and motility and finally death from paralysis of the heart and respiration, with or without convulsions, consciousness being preserved until near the end, when carbon dioxide narcosis sets in.

Uses.—It antagonizes the fever process, when properly used is a most valuable drug; it is indicated in all affections, characterized by high resisting pulse, dry, hot skin and elevated body temperature; is useful in acute throat affections as laryngitis, pharyngitis and perotiditis, in small doses often repeated. Indicated in acute inflammation of the organs of respiration. For pleurisy and perotiditis, at the outset, give aconite with opium. Aconite is indicated in simple fevers or in puerperal fever, inflammation of the brain; in acute or inflammatory rheumatism, in acute local inflammation, as arthritis or inflammation resulting from bruises, sprains, etc.

In lymphangitis, laminitis and enteritis, if called in first stages of enteritis give 20 ms. of aconite and repeat with 10 or 15 ms. every hour and between times gives fluid extract of belladonna 15 to 20 ms. every hour and externally woolen blankets wrung out of hot water and wrapped around the body.

In mammitis is also useful in large doses, combined with phytolacca; in spasmodic colic brought on by drinking cold water, give 30 to 60 ms. of the tincture of aconite with other colic mixture; in congestion of the bowels or liver, or in congestion of any part, small repeated doses are better than large ones. It is also advantageously used in lung disorders.