Piscidia.—Jamaica Dogwood.
Related entries: Franciscea.—Manaca
The bark of the root of Piscidia Erythrina, Jacquin.
Nat. Ord.—Leguminosae.
COMMON NAME: Jamaica dogwood.
ILLUSTRATION: Nuttall's North American Sylva, Plate 52.
Botanical Source and History.—This is a small tree, native of the West Indies, and known as Jamaica dogwood. It is rarely found in southern Florida. The flowers are in lateral clusters, appearing in profusion before the leaves. They have a broad, bell-shaped, 5-toothed calyx, and a papilionaceous corolla, of a dirty white color tinged with purple. The leaves are unequally pinnate, with entire, oval, acute leaflets, resembling those of the coffee-nut tree. The fruit is a 4-winged legume. The bark of the tree is very astringent, and is said to have been used in tanning. It is much employed in its native country as a fish poison (whence the generic name of the tree). It seems to act upon the lower animals as a poisonous narcotic.
Description.—Piscidia bark comes in quilled pieces, or in curved or flat sections. The corky layer is of a vivid orange (occasionally whitish) color, and is rugose, or appears fissured. Upon removal of the cork a deep ashen-gray surface appears, somewhat tinted with a brownish or blackish shade and is marked with sinuous, longitudinal striae, as well as by small ridges transversely arranged. Internally, it is smooth (sometimes fibrous) and of a brownish hue. The interior of the bark is bluish-green or brown-green, probably due to chlorophyll. It breaks with a fibrous, tough fracture, giving a narcotic, opium-like odor, and its taste, though slight at first, soon becomes acrid and bitter.
Chemical Composition.—The bark exhibits crystals of apparently oxalate of calcium, which, however, are phosphate of calcium (Berberich, 1898). According to Edward Hart (Amer. Jour. Pharm., 1883, p. 369), the active principle is a neutral body, piscidin (C29H24O8), which is neither a glucosid nor an alkaloid. It is produced by mixing 1 pound of the fluid extract of piscidia with 30 grammes of slaked lime, digesting for ½ hour, filtering, adding water in small amounts until the liquid becomes turbid; upon standing for 2 or 3 days the crystalline principle falls out, contaminated with some resin. They are finally recrystallized by means of alcohol. The principle occurs in prismatic, nearly colorless crystals readily soluble in chloroform, in boiling alcohol, and benzol, sparingly in cold alcohol and ether, insoluble in water. The crystals are also dissolved by strong acids, and from this solution are precipitated, apparently unchanged, by the addition of water. Its melting point is 192° C. (377.6° F.). These results were fully confirmed more recently by H. Berberich (Amer. Jour. Pharm., 1898, p. 424), who made a complete analysis of the bark. Beside the active principle, piscidia (piscidin), some resin, caoutchouc, wax and fat, starch (1.34 per cent), were present; tannin was not found.
Action, Medical Uses, and Dosage.—Jamaica dogwood possesses active properties, its chief uses being to control pain and to produce sleep. Dr. Isaac Ott (see Pharmacology of Newer Materia Medica, p. 597), who made extensive experiments with the drug, declares its physiological effects to be essentially as follows: It increases the salivary and cutaneous secretions; slows the pulse, increases the arterial tension, succeeded by a fall of tension due to a weakening of the heart; dilates the pupils, except when passing into a state of asphyxia, when contraction takes place; it does not affect the irritability of the motor nerve fibers, nor does it attack the peripheral sensory nerve endings; it reduces reflex action by stimulating Setschenow's centers, and induces a tetanoid condition by stimulation of the spinal marrow; finally, he pronounces it narcotic to frogs, rabbits, and men. Piscidia destroys life by causing heart failure or by arresting respiratory action. Unpleasant results have been occasioned by even small doses of piscidia; among these are nausea, vomiting, headache, etc. Convulsions were provoked in the case of a woman who had been given a ½- drachm dose for hemicrania. The drug is recommended to replace opium, chloral, and similar narcotics. Dr. Hamilton (Burnett's Outlines, p. 684) states that a tincture of the bark of this tree is, the same as the bark itself, astringent and irritating. He also observes that it is most powerfully and remarkably narcotic and diaphoretic, and that its local application is a specific in removing toothache. For the latter purpose it has also been applied locally and given internally at the same time, in irritation of the dental pulp, inflammation of the peridental membrane, alveolar abscess, as well as in other painful affections of the mouth. Burns, scalds and hemorrhoids have been relieved by it, while a solution of it has been recommended as an injection in gonorrhoea (Fearn). Internally administered, it relieves pain, overcomes spasm, allays nervous excitability, and induces sleep. It is a favorite remedy in prolonged insomnia, particularly in the aged, and in those of an excessively nervous temperament. It should at least be given the preference over opiates until its utility or non-utility is established. It has rendered good service in neuralgia—particularly sciatica, abdominal neuralgia, renal neuralgia, migraine, and tic-douloureux. It allays the pain of cholera morbus, and the gastro-enteralgia sometimes following enteric fever. It also relieves painful spasms of the muscles and acute articular and other forms of rheumatism. In the disorders of women it has rendered excellent service in alleviating neuralgic and other forms of dysmenorrhoea and in various pelvic neuroses. With viburnum, it has been administered to check false labor-pains and threatened abortion. Hysterical convulsions, delirium tremens and the insomnia of insanity have yielded to it. In the pain of carcinoma and that attending fractures, it has been preferred by some to opium and other anodynes. It relieves the spasmodic element of pertussis and asthma, and has been lauded for reflex coughs and the cough of spasmodic and chronic bronchitis, and pulmonary consumption. Foltz (Webster's Dynam. Therap., p. 595) praises it in neuralgia of the eyeball (where opium was not tolerated) and in supraorbital neuralgia, the dose given being from 10 to 20 drops of the fluid extract every 2 or 3 hours. He speaks lightly of it for the relief of pain in acute catarrh of the tympanum. Others speak highly of it in acute abscess of the external auditory canal and in iritis, panophthalmitis, and other inflammatory and painful affections of the eye. The dose of the fluid extract ranges from 10 drops to 2 fluid drachms; of specific Jamaica dogwood, 10 to 60 drops.
Specific Indications and Uses.—Insomnia and nervous unrest; to allay spasm, control pain and allay nervous excitability; migraine; neuralgia.