Definition. - It should contain not less than 99.5 per cent. of pure phosphorus.

Origin. - It exists, chiefly as phosphates, in many minerals and in all plants and animals. It is prepared by treating calcined bones with sulphuric acid, evaporation, and distillation.

Description and Properties. - A translucent, nearly colorless solid, of a waxy luster, having at ordinary temperatures about the consistence of beeswax. When kept for some time the surface becomes red and occasionally black. Phosphorus has a distinctive and disagreeable odor and taste (tasting being allowable only in the form of extreme dilution). When exposed to the air it emits white fumes, visible in the dark, which have an odor somewhat resembling that of garlic. Upon prolonged exposure to air it takes fire spontaneously.

Phosphorus is insoluble, or nearly so, in water, to which, however, it imparts its characteristic disagreeble odor and taste. It is soluble in 350 parts of absolute alcohol, in 80 parts of absolute ether, and in about 50 parts of any fatty oil. It is very soluble in chloroform or in carbon disulphide, the latter yielding a solution to be handled with the greatest care to prevent accident from combustion. The drug should be carefully kept under water, in strong, well-closed vessels, in a secure and moderately cool place, protected from light.

Dose. - 1/100-1/30 grain (0.0006-0.002 Gm.) [1/128 grain (0.0005 Gm.), U. S. P.].

Official Preparation

Pilulae Phosphori - Pllulas (ace.) Phosphori - Pills of Phosphorus. - Dose, one or two pills. Each pill contains 1/100 grain (0.0006 Gm.) of phosphorus.

Antagonists and Incompatibles. - The principal chemical antidotes are hydrated magnesia, lime water, powdered charcoal, copper sulphate, and old acid turpentine.

Synergists. - Oily or fatty substances generally aid the action of phosphorus by increasing its absorbability. Cod-liver oil and the restoratives generally aid the action of phosphorus.

Physiological Action. - Externally and Locally. - Applied to the skin, phosphorus causes local inflammation, ulceration, and possibly gangrene. The fumes, so common in factories in which phosphorus is used - i. e., in making matches - may produce the most serious results - even maxillary necrosis where dental caries is present, as well as great irritation of the conjunctivae and the respiratory mucous membrane. The graver systemic symptoms are confined to the conditions induced by toxic doses of the drug.

Internally. - Digestive System. - Taken into the stomach, no special effect is apparent as a result of small doses, save that the drug acts as a functional stimulant. Ferment action is not impaired by non-poisonous doses. Large non-toxic doses cause irritation, with anorexia, increased peristalsis, diarrhea. Fatty degeneration of the cells of the mucosa is readily induced.

Circulatory System. -The primary action is stimulating, the pulse-rate rising and acquiring more force, though not firmness. The facial capillaries are dilated, often congested; the cutaneous circulation becomes more rapid; and diaphoresis is produced. Under toxic doses the action of the heart is strongly depressed.

Nervous System. - Small or moderate doses act as general stimulants to the entire nervous system. Toxic effects include coma, and occasionally vertigo, with delirium, convulsions, insensibility, and collapse.

Respiratory System. - The deleterious action of the fumes of phosphorus is exemplified in their irritating effect upon the broncho-pulmonary mucous membrane. Toxic symptoms are often accompanied by serious disturbances, respiratory failure being among the immediate causes of death. Small doses of phosphorus have no marked action on the function of respiration.

Liver, Bones, and Metabolism. - Phosphorus acts very markedly upon the cells of the liver. Its chief action, apart from certain corrosion effects, may be said to be exerted on this organ. In small doses it probably induces a specific irritation whereby the normal functions of the liver are enhanced. More bile is produced, and it is more highly pigmented. Possibly the so-called tonic properties of phosphorus are dependent on this, as yet little understood, increase in biliary activity. But phosphorus, even in small doses, soon brings about retrograde changes in the liver cells. With these is associated a certain loss in the oxidative properties of this organ. The production of ammonia, leucin, and tyrosin, which are found in the excreta, and the presence of lactic acid in the blood and tissues, seem to show that this loss is one of the early changes induced in the liver cells by this drug. Further irritation leads to engorgement of the organ, mechanical difficulties in the elimination of the bile formed, and general jaundice. Further fatty degeneration takes place, either as a result of the lessened oxidative capacity of the liver, or as a concomitant, and more serious metabolic disturbances occur, which cannot be entered on here. The general fatty degenerations caused are discussed in the paragraph on Poisoning.

The bones also are the site of a specific effect of phosphorus action. This consists largely in a specific irritation of the bone-forming cells, by which they are increased in number and ossifying cartilage lays down more bone than is normally formed. Over-irritation leads very readily to destruction of bone-formation and to necrosis.

Kidneys. - Phosphorus irritates the kidney epithelium. There is albuminuria; fatty casts and blood may even appear in acute poisoning. The urine is increased in amount under small doses. Diminution of urine and anuria, as well as other changes in the substances found in the urine, are symptoms of intoxication.

Absorption and Elimination. - The modus operandi of absorption is a matter of some dispute. Absorption is very slow, and if much phosphorus be ingested it may pass through with the feces. Probably a portion of the drug undergoes oxidation in the stomach, and the phosphoric acid formed, combining with the alkalies, enters the blood as phosphates. A part of the phosphorus is dissolved in the fats and oils present in the stomach, probably entering the circulation as elementary phosphorus.