Origin.—Cinchona is obtained from the bark of a tree (Cinchona Calisaya), which grows in South America, East Indies and Jamaica. It contains at least five per cent of its peculiar alkaloids, of which not less than one-half should be quinine sulphate, which is the most important.

Actions.—Cinchona is an astringent. Other than that cinchona and its alkaloids possess the same actions, that being, bitter tonic, stimulant, antiseptic, antiperiodic, antipyretic, antiphlogistic, antimiasmatic, stomachic and antiferment. Large doses are general depressants.

Uses.—Cinchona and its alkaloids are recommended for all classes of patients as bitter stomachic and tonics. They stimulate the appetite, check abnormal gastro-intestinal fermentation and counteract relaxed conditions of the intestines and the accumulations of mucus, which prove favorable to the development of worms.

In troublesome cases of atonic indigestion in horses respond rapidly when quinine sulphate is frequently given in thirty to forty grain doses with half a drachm of dilute nitric or hydrochloric acid. Weak foals and calves suffering from relaxed condition of the bowels, following a dose of castor oil are often much benefited by a few doses of cinchona bark, hydrochloric acid dilute and brandy.

Few medicines are so effectual as cinchona bark or quinine sulphate in improving appetite and muscular strength and hastening convalescence from debilitating disease.

They are advantageous in anaemia joined with iron salts.

Good results are obtained from cinchona or quinine in the earlier stages of tuberculosis, in septicaemia and pyaemia in all animals; in influenza, protracted cases of strangles, purpura and other similar diseases of the horse; in septic metritis in cows and ewes and in lingering cases of distemper in dogs. Their beneficial effects in these and other diseases probably depending on the action of quinine on micro-organisms or their products. It is often useful in rheumatism conjoined with salicylic acid or potassium iodide. Administered with cathartics, like other bitter tonics, it generally increases their activity. Alternated with cod liver or olive oil and iron, quinine is the best tonic for weak dogs and those suffering from chorea.

Quinine and urea hydrochloride has recently come into use as local anaesthetic. One per cent solutions make a satisfactory substitute for cocaine, etc. It also has advantages over cocaine. It is non-toxic, it may be exposed to a boiling temperature and its anaesthetic effect for dogs after an operation, therefore aiding in dressing of wounds. Its anaesthetic effect comes on within five minutes to half an hour after being injected into the intended seat of operation.

Speaking from practical experience, I prefer quinine and urea hydrochloride to cocaine or any of its allies.

Dose.—Of the powdered cinchona bark: Horses, 2 dr. to 1 oz.; cattle, 1 to 2 oz.; sheep and pigs, 1 to 4 dr.; dogs, 10 gr. to 1 dr.

ALKALOIDAL SALTS OF CINCHONA—QUININAE SULPHAS—SULPHATE OF QUININE

Dose.—As a tonic: Horses, 15 gr. to 1 dr.; cattle, ¹/₂ to 1¹/₂ dr.; sheep and pigs, 5 to 10 gr.; dogs and cats, 1 to 2 gr. As antipyretic Dose: Horses and cattle, 2 to 4 dr.; sheep and pigs, 15 gr to 1 dr.; dogs and cats, 5 to 10 gr.

QUININAE ET UREAE HYDROCHLORIDUM—QUININE AND UREA HYDROCHLORIDE (NON-OFFICIAL)

Soluble in 18 parts of water. Use hypodermically as a local anesthetic.