Origin. - Prepared by neating copper and sulphuric acid together, dissolving the soluble product in hot water, and evaporating.

Description and Properties. - Large, transparent, deep-blue, triclinic crystals, odorless, of a nauseous, metallic taste; slowly efflorescent in dry air. Soluble in about 2.6 parts of water and in 0.5 part of boiling water; almost insoluble in alcohol.

Dose. - 1/8-1/2 grain (0.008-0.03 Gm.) [1/2 grain (0.03 Gm.), U. S. P.] as an astringent; as an emetic, 2-20 grains (0.12-1.2 Gm.) [4 grains (0.24 Gm.), U. S. P.].

Antagonists and Incompatibles. - Alkalies and their carbonates, the sulphides, mineral salts (except the sulphates), lime water, the iodides, and vegetable astringents.

Physiological Action. - Copper sulphate is the salt mostly used, and the only official preparation. Its action is therefore given as characteristic of that of cuprum.

Externally. - Applied to the unbroken skin it produces little effect, but on raw surfaces or mucous membranes it acts as an astringent. In large quantities it acts as a caustic. It also possesses antiseptic properties.

Internally. - Digestive System. - It acts as an irritant, causing vomiting of greenish matter, though nausea does not follow the emesis. The secretions are augmented, and salivation and purging of blood and mucus are attendant consequences of its ingestion. Should emesis be delayed, the stomach should immediately be emptied, otherwise the copper is liable to produce inflammation.

Circulatory System. - Copper exists normally in the blood and acts as a tonic, being present in the circulation as an albuminate, or, as Robert describes, a new compound, cuprohaemal. It depresses the heart's action, causing a small, weak, rapid pulse.

Nervous System. - It acts as a depressant.

Respiratory System. - Its influence is to hasten and depress the respiratory movements.

Absorption and Elimination. - Copper salts are slowly absorbed, tending to accumulate in the liver. The drug is eliminated by the liver, kidneys, salivary glands, and intestinal canal.

Poisoning. - Acute poisoning results from the inhalation of cupreous fumes, eating fruits cooked in copper vessels, or from an overdose of a copper salt.

When inhaled the first symptoms are those of bronchial catarrh and irritation. Internally administered, the symptoms do not usually appear at once, but after an hour's interval there are manifest a strong metallic taste in the mouth, burning and constriction of the pharynx and fauces, salivation and vomiting of greenish matter, and purging, the passages after a while containing mucus streaked with blood. There are present also burning in the epigastrium, and griping, colicky pains.

Copper enters the circulation quickly, it being highly diffusible. A characteristic symptom of poisoning is a green line on the gums. Sometimes jaundice may be present, and headache, convulsions, suppression of urine, cardiac depression, and hurried respiration are among the graver symptoms.

Treatment of Poisoning. - A chemical antidote should be given at once, potassium ferrocyanide being the best, as it forms an insoluble copper cyanide. Other recourses are white of egg, milk, sweet oil, emetics, and the use of the stomach-pump. A mustard plaster, with a little opium added to allay the pain and irritation, may be applied over the pit of the stomach as a counterirritant. Should vomiting have already occurred, emetics should be withheld.

Chronic poisoning is thought to result from long-continued use of the medicine or from taking minute quantities of copper as found in the many foods that are treated with copper salts. The acute symptoms are described the same as those of acute poisoning, with the following superadded: paresis of the limbs, paralysis, inco-ordi-nation of muscles, atrophy of the liver, with fatty degeneration of the liver-cells, and proliferous growth of the connective tissue. There may also be present congestion of the lungs and fatty degeneration of the kidney, together with bronchial catarrh. It is by no means certain that these symptoms are due to the copper alone or to lead and arsenic, which are so frequently associated with it, particularly in foundries, etc., where these symptoms are noted. In view of the value of copper as a general disinfectant, the metal and its salts being markedly bactericidal, the question of chronic poisoning merits detailed investigation.

Therapeutics. - Externally and Locally. - Copper sulphate stimulates old, flabby, granulating ulcers. Ringworm, scabies, and tinea sycosis derive great benefit from its use.

The crystal or solution, 2 grains to 1 ounce (0.12-32.0 Gm.) of water, is used extensively in conjunctivitis, tinea tarsi, and trachoma condylomata, and as a gargle in relaxed sore throat. The aphthae in aphthous stomatitis are benefited by touching with the copper sulphate solution. It is also used as an injection in gonorrhea and gleet, 2 grains to 1 ounce (0.12-32.0 Gm.). It is also valuable in mercurial sore mouth and gangrene of the pharynx.

Internally. - Copper sulphate is the chemical antidote for phosphorus-poisoning, yet it should be given with great caution, lest of itself it produce acute poisoning. It is a speedy emetic, since it acts directly upon the stomach. If emesis is not produced by the first dose, sulphate of zinc or mustard may be employed. It is used as an emetic in croup.

In chronic dysentery and diarrhea an enema of a pint of water (512.0 Gm.) and 10 grains (0.64 Gm.) of sulphate of copper is an efficient remedy, being by some authors considered the best metallic astringent in chronic dysentery.

Copper associated with arsenic is highly beneficial in anemia.

Oleate of copper is used in the skin affections mentioned.

Nitrate and acetate of copper act like the sulphate.

Arsenite of copper has been suggested as a remedy in anemia, and has been used in doses of 1/100 grain (0.0006 Gm.) in diarrhea and cholera infantum.

Administration. - For an enema in diarrhea and dysentery it may be combined with opium -2 grains to 1 ounce (0.12-32.0 Gm.) of water being used. For eye affections the crystal or solution is employed. In addition to the enema, copper sulphate, 1 grain (0.06 Gm.), may be united with magnesium sulphate 1 ounce (32.0 Gm.) and 1 dram (4.0 Gm.) of diluted sulphuric acid in 4 ounces (128.0 Gm.) of water, a tablespoonful of the mixture being given every three or four hours. To produce emesis 10-15 grains (0.6-1 Gm.) are dissolved in about 5 ounces (160.0 Gm.) of water, a tablespoonful being given every ten minutes until vomiting is produced.