Origin. - The sclerotium of Claviceps purpurea (Fries) Tulasne (Fungi), replacing the grain of rye, Secale cereale L. Most of the commercial article comes from Spain and Russia.

Description and Properties. - Somewhat fusiform, obtusely triangular, usually curved, about 3/4 to 1/4 inches (2-3 Cm.) long and 1/8 inch (3 Mm.) thick; three-fr.rrowed, obtuse at both ends, purplish-black, internally whitish, with some purplish striae, breaking with a short fracture; odor peculiar, heavy, increased by trituration with potassium or sodium hydrate T. S.; taste oily and disagreeable. Old ergot, which breaks with a sharp snap, is almost or entirely devoid of a pinkish tinge in the fracture, is hard and brittle between the teeth, and comparatively odorless and tasteless, should be rejected.

Ergot should be but moderately dried and preserved in a closed vessel, with a few drops of chloroform added from time to time to prevent the development of insects. When more than one year old it is unfit for use.

The active constituents of ergot are not definitely ascertained. It contains, however, an acid soluble in water and variously termed sderotinic, ergotinic, and ergolic acid, and another, soluble in alkalies, known as sphacelic acid. Both of these acids possess ecbolic properties. Kobert isolated a principle known as cornutine. 30 per cent. of a yellow non-drying saponifiable fixed oil, besides proteids, sugar, tannin, and ash are also present. The commercial ergotin is merely a purified aqueous extract of ergot.

Jacobj has more recently isolated two bodies: one, sphacelotoxin, which produces gangrenous effects, and chrysotoxin, which acts somewhat like Kobert's cornutine.

Dose. - 5-60 grains (0.30-4.0 Gm.) [30 grains (2 Gm.), U. S. P.].

Official Preparations

Extractum Ergotae - Extraicti Ergotae - Extract of Ergot. - Dose, 2-10 grains (0.12-0.6 Gm.) [4 grains (0.25 Gm.), U. S. P.].

Fluidextractum Ergotae - Fluidextracti Ergotae - Fluidextract of Ergot. - Dose, 15-60 minims (1.0-4.0 Cc.) [30 minims (2 Cc), U. S. P.].

Vinum Ergotae - Vini Ergotae- Wine of Ergot. - Dose, 1-3 fluidrachms (4.0-12.0 Cc.) [2 drachms (8.0 Cc), U. S. P.].

Antagonists and Incompatibles. - The cardiac and motor depressants antagonize the action of ergot. Caustic alkalies and metallic salts are chemically incompatible.

Synergists. - Its action upon the circulation is aided by digitalis and belladonna; upon the nervous system by strychnine; while ustilago, hydrastine, gossypium, and the emmenagogues enhance its influence upon the uterus.

Physiological Action. - Externally and Locally. - Ergot has no distinctive action upon the skin, but upon mucous membranes its influence is that of an astringent, possessing hemostatic properties.

Internally. - Digestive System. - In large doses it is a gastrointestinal irritant, occasioning considerable heat and dryness of the throat, accompanied by thirst and succeeded by pain in the stomach and bowels, vomiting, and occasionally purging, with violent per-istalis, although constipation is the commoner sequence.

Circulatory System. - Repeated medicinal doses increase the blood-pressure and render the pulse slower and smaller, the result principally of stimulation of the vasomotor center in the medulla, with possibly some influence upon the heart or the walls of the arterioles. Jacobj thinks that sphacelotoxin is the chief agent in causing the contraction of the arteries, and that its activities are exerted both centrally and peripherally.

The heart muscle itself seems to be stimulated secondarily only.

Nervous System. - Medicinal doses have no especial action, though excessive doses sometimes depress the sensory mechanism, producing general cutaneous anesthesia.

The action of toxic doses on the nervous system will be described under "Poisoning."

Medulla. - Ergot has a distinct action on the medulla, stimulating the respiratory and cardio-inhibitory centers, and acting as a distinct stimulant to the vasoconstrictor apparatus. Its action on circulation is thus marked.

Respiratory System. - Medicinal doses produce a mild stimulation of the respiratory center.

Absorption and Elimination. - The actual constituents of ergot are rapidly absorbed into the blood, and are eliminated principally by the kidneys, increasing the urinary flow.

Temperature. - No special action has been observed.

Eye. - The caliber of the retinal and nutrient opticus bloodvessels is reduced, resulting in marked pallor of the disk, transitory amblyopia, and papillary anemia.

Uterus. - Probably the most important action of ergot is upon this organ. It produces in full doses tetanic, tonic contraction of the uterine muscle, the uterus becoming hard and pale, and forcing the blood out of the uterine arterioles. The organ is more sensitive to the action of the drug during pregnancy.

The precise manner in which ergot affects the uterus is still a matter of discussion. It is fairly demonstrated, however, that the drug acts both centrally and peripherally.

It is doubtful if any drug in our Materia Medica has been more carefully studied than ergot, and, if opinions differ widely as to its modus operandi, it is because we have to deal with a very complex substance, the nature, and even the number, of whose constituents are as yet inadequately known. Many principles of the drug are unstable and variable in their action, certain preparations differing decidedly from others in their influence, as, for instance, Tanret's ergotinine, which has no effect upon the uterus. Bonjean's ergotin is a powerful ecbolic, and has a marked action, moreover, upon the vascular system, whereas Wigger's ergotin is inert. Kobert's cornu-tine is probably not a pure principle, and his ergotinic acid is not a true principle. Jacobj's principles are those last isolated.

Untoward Action. - In addition to the gastro-intestinal disturbances already described, there are occasionally produced headaches, mental confusion, dizziness, a feeling of chilliness, muscular weakness, dilatation of pupils, and glimmering before the eyes.