Acidum Oxalicu

Oxalic Acid

Properties

Oxalic acid occurs in flat oblique rhombic prisms, transparent, colorless, soluble in about eight parts of cold water, and in nearly all proportions in boiling water. It is strongly acid to the taste and in reaction, and combines with bases to form salts. Dose, gr. 1/8 to gr. ss.

Actions and Uses

In sufficient doses it is an irritant poison, causing nausea, vomiting, and gastro-intestinal inflammation. The matters brought up assume a brownish hue and presently become bloody. Intense burning pain occurs, and profound depression comes on, terminating in collapse. Very large doses may be rejected by vomiting, and no further symptoms occur. In ordinary toxic quantity, oxalic, besides the local gastro-intestinal inflammation, affects the action of the heart, which becomes feeble and intermittent, and death ensues by cardiac failure, with stupor, coma, and insensibility, and sometimes convulsions. In some rather exceptional cases the gastro-intestinal symptoms are comparatively mild, and the force of the poison is expended on the nervous system. In such examples there ensue stupor, general muscular paralysis, and finally complete loss of consciousness; or, with but little gastro-intestinal disturbance, the patient passes at once into coma and complete muscular resolution. It does not act on the peripheral nerves.

In experiments on animals, it has been ascertained that repeated administration in moderate doses sets up oxaluria, and subsequently albuminuria with tube casts (Kobert). The same observer found that the exhibition of non-toxic quantities caused a form of glycosuria to appear. Whether this is due to the local action of the poison at the point of excretion, or to an interference with the amylolytic transformations of the primary assimilation, remains undetermined. It is certainly true the oxalates form concretions that line the tubules of the kidneys in rabbits, and must therefore exercise some irritant action along the points of contact. In what way soever determined, it is an interesting fact that oxalic acid causes albuminuria and glycosuria when administered to animals, and the presence of sugar in the urine has been ascertained in some cases of poisoning in man.

Oxalic acid has powerful germicide properties.

Poisoning by this agent is to be treated on the same general principles as the mineral acids.

Therapeutically, it is indicated in the treatment of albuminuria with tube casts on the principle of antagonism. In the same way it may be applied to the treatment of diabetes, since it causes glycosuria in man. It is said, also, to be an efficient remedy in amenorrhoea. It is indicated in cases requiring an active stimulant to the uterus and ovaries.