Formula

C2Hc13o2.

Derivation

Trichloracetic acid is prepared by the oxidation of hydrate of chloral by means of nitric acid. It consists of colorless, rhombic deliquescent crystals. It belongs to a group of three acids, the other two being the monochloracetic and the dichloracetic acids, and the difference in their composition is due to the proportions of chlorine they contain. They have similar properties.

Medical Properties And Action

Trichloracetic acid in its full strength is a very powerful escharotic and styptic. It is readily soluble in water and alcohol, with an agreeable odor. It coagulates albumen, and its concentrated solutions are powerfully caustic. Diluted solutions cause an increased secretion of saliva, and destroy its power to convert starch into sugar; it also arrests the digestive action of pepsin. As an antiseptic it has been employed in putrid and indolent wounds, in the form of weak solutions, which are unirritating, and promotes healthy granulations and cicatrization ; it has also been employed externally in erysipelas and venereal sores. Internally, it has been recommended by Dr. Filippowitch as a preventive of cholera, in doses of gr. ij to iij, three or four times daily. Externally, it is employed in one or two per cent. solutions. The common dose is gr. ij to v, in very dilute solutions, three times a day.

Therapeutic Uses

Trichloracetic acid is stimulant, refrigerant, antiseptic, escharotic and styptic, and a solvent of calculi. It is also a powerful caustic and escharotic; diluted with water to a strength of three per cent. it is an efficient astringent and stimulant, and diluted to a strength of one per cent. it is useful as a refrigerant mouth wash. It coagulates albumen, and its concentrated solutions are caustic. Diluted solutions cause an increased secretion of saliva, and destroy its power to convert starch into sugar; it also arrests the digestive action of pepsin. It is employed as an antiseptic in the treatment of putrid and indolent wounds, in the form of weak, unirritating solutions, and promotes healthy granulations and cicatrization; it has also been employed externally in erysipelas and on venereal sores. Externally, it is generally employed in one or two per cent. solutions. It destroys all forms of organic life in such a percentage; and in five per cent. solution it arrests the growth of bacteria and other forms of micro-organisms. Internally, it has been administered in cholera, gastric catarrh, etc., in doses of grains ij to iij: for summer complaint of children, the dose is 1/2 to 1 grain, 3 times daily.

Dental Uses

Trichloracetic acid is employed in dental practice as an escharotic in the treatment of pyorrhoea alveolaris, on account of its destructive effect on pus secreting surfaces of the alveoli of teeth, for which purpose a ten per cent. solution is applied. It is also employed for the removal of vascular tumors of the pulp, and hypertrophy of the margins of the gums, and epulis. It destroys hypertrophied gum tissue, and when such tissue has grown into and filled up carious cavities in teeth, and been cut away, and the profuse hemorrhage interferes with the filling, an application of trichloracetic acid will not only remove such tissue, but arrests the hemorrhage in a few minutes.

Dr. Kirk speaks of using this acid in the strong solution of about ninety per cent. for the removal of such growths. Trichloracetic acid has also a solvent effect on calculi upon the roots of teeth and on necrosed bone, a ten per cent. solution in water being recommended, and has also been employed on the overhanging and resistant gum of third molars. One application to the pus-pockets of alveolar pyorrhoea, will cleanse the surface of the alveolus and the diseased tissue lining the pocket, and remove any calculi present; any subsequent applications should be not stronger than four per cent. solutions. When used in full strength, it should be followed with bicarbonate of soda to counteract the effect. A one per cent. solution has been successfully employed as a mouth wash, for its astringent and stimulating action in inflammations and ulcerations. It is also used in combination with pyrozone in the treatment of alveolar pyorrhoea, and in such a solution, as well as alone, its effects have been remarkably satisfactory. Trichloracetic acid may be combined with any suitable alkaline solution, such as soda or magnesia, when it is desirable to limit its action. It has a peculiar power to soften and remove sanguinary deposits, and it acts without injury to the teeth or soft tissues.

Diluted with water to a three per cent. solution it is an excellent local astringent and stimulant. Dr. Harlan recommends it for removing the overlying gum for third molars, as it destroys the tissue without hemorrhage or subsequent soreness. Trichloracetic acid is also employed to gain access to roots of abscessed teeth through a fistulous opening, one crystal followed by more being placed in the fistula; it is also used for removing gum polypi, in necrosis of the bones of the jaws, and for hyper-trophied gums.