Hc1. Sp. gr., 1.16.


Hydrochloric or Muriatic Acid is obtained by the action of sulphuric acid on a solution of chloride of sodium or common salt. When pure, it is a transparent, colorless liquid, but when contaminated with chlorine, iron and other substances, it has a yellow color. It emits a dense, white vapor, with a pungent odor and a corrosive taste, being an active poison. The antidote is magnesia or soap.

Medical Properties And Action

The strong acid is a powerful caustic and escharotic; also disinfectant and fumigant, but inferior in its disinfectant properties to those of chlorine. For internal use the dilute acid, which is tonic, refrigerant and astringent, is employed, acidum hydrochloricum dilutum, - diluted hydrochloric acid, which is prepared by diluting the strong acid so that four ounces of the acid are contained in a pint of diluted acid. It is of a deep yellow color, and emits the odor of chlorine, which is its principal constituent.

Therapeutic Uses

The dilute hydrochloric acid is internally employed in the treatment of calculous affections, gout, atonic dyspepsia, typhus and typhoid fevers, continued fevers of childhood, syphilis, chronic whooping-cough, phthisis, etc., and externally in diphtheria, ulcerated sore throat, cynanche maligna, etc.


Of dilute hydrochloric acid, m x to m xxx, freely diluted; otherwise, when swallowed, it is highly irritant and corrosive.

Dental Uses

The strong acid is employed in the dental laboratory for dissolving zinc, in the preparation of flux for soldering certain metals.

The strong acid is also employed as a local application in gangrenous stomatitis or cancrum oris, for arresting the ulcerative process; but care is necessary in its use, on account of its powerful action. Combined with equal parts of glycerine it is useful in inflammation and ulceration of the oral mucous membrane; also, the same combination in cases of sloughing will induce a healthy form of inflammation, and to limit its application to the parts on which it is to act, collodion may be applied. For mild cases of inflammation it may be diluted with an equal amount of honey.

In aphthous ulcerations of the mouths of children, it is often a useful application.

Dental Formulae

For Aphtha.

Acidi hydrochlorici . I part Mellis . . ... 8 parts. M.


Apply with a camel-hair pencil.

Signa 489

For Chronic Inflattimation of Mucous Membrane and Gums. Acidi hydrochlorici diluti.......

Infusi cinchonae . . Mellis ......

Fiat gargarysma.

Signa 490Signa 491

For Ulceration of Mucous Membrane.

Acidi hydrochlorici diluti .....


Aquae destillatae . .


To be used as a gargle.

Signa 492Signa 493

For Scorbutic Gums.

Acidi hydrochlorici di luti.......


Aquae rosae . . . . aa SlGna. - Apply with a camel-hair pencil 3 or 4 times a day.

Signa 494Signa 495