CUTANEOUS DISORDERS.—In cutane ous disorders, especially those in which the mucous layer is principally involved, tar is an effective remedy. In eczema and psoriasis the tarry preparations are very useful, and are more effective when applied directly to the diseased surface. In eczema it gives the best results when applied after the subsidence of active inflammation; if begun earlier it is apt to aggravate the disease; the indications for the use of tar is a condition of sub acute inflammation accompanied by a dry, scaly surface, with more or less hyperaemia and pruritus, inflammatory products still remaining in the tissues. It is best to begin with a mild prepara tion: Tar ointment, 1 part; zinc oint ment, 3 parts. Stronger applications may be made later. The applications of tar may be continuous or intermittent.
In the dry chronic eczema of children the following is useful: Tar, 1 part; precipitated sulphur, 1 part; zinc oint ment, 16 parts. Mix and apply night and morning (Hare).
Bulkley advises liquor picis alkalinus in the treatment of chronic eczema.
For psoriasis tar may be used as a stimulant in the same manner, but it is not so much used as formerly, having been superseded by chrysarobin.
Tar, in the form of soap, ointment, or liquor picis alkalinus (Bulkley), may be used in the treatment of scabies, tinea capitis, and lepra.
Care should always be taken in apply ing tar, lest it excite dermatitis or acne picealis.
In prurigo tar is often valuable. In pruritns ani a weakened tar ointment will often afford relief.
A useful application to hemorrhoids is the following: Tar and alcoholic ex tract of belladonna-leaves, of each, 45 grains; glycerite of starch, 1 ounce. This is to be applied morning and even i ng.
Tar ointment in full strength, or modified, will be of service in lichen, comedo, sycosis, pemphigus, lupus ery thematosus, and lupus vulgaris. Stern has observed that, when tar is allowed to stand in a warm place for several weeks, it separates into two layers, the upper of which is thin, syrupy, and devoid of irritant properties; an ointment pre pared with this is advised when a mild effect is desired.
Derivatives and Allied Compounds. LYSOL.—Lysol is an antiseptic prepara tion made by dissolving in fat, and sub sequently saponifying with alcohol, that part of tar-oil which boils between 374° and 392° F. It occurs as a clear, brown, oily-looking liquid, having a feeble, aromatic, creasote-like odor. It con tains 50 per cent. of cresols, is miscible with water, forming a clear, soapy, froth ing liquid. It is also soluble in alcohol, chloroform, glycerin, etc. Lysol is five times stronger than carbolic acid, and eight times less poisonous. It is used in 0.3- to 1-per-cent. solution for dress ing wounds and injuries, in diphtheria, and in cutaneous disorders.
In 2- to 4-per-cent. solution it may be used for disinfecting the hands and surgical instruments. Haenle claims that it does not affect the operator's hands unpleasantly, but renders the skin soft and supple. It has also been used and recommended in gynxcology and general surgery by Cramer, Parvin, Haenle, Michelsen, etc., and in skin dis eases by firma and others (especially in lupus by Leslie Phillips). Upon mucous membranes a stronger solution than 2 per cent. should not be used. Lysol has been given internally in dyspepsia in doses of to S grains after meals, the taste being disguised by spirit of pepper mint.
PixoL.—This disinfectant is made by dissolving 1 pound of green soap in 3 pounds of tar, and slowly adding a solu tion of a little more than ounces of either potassium or soda dissolved in 3 pints of water. This makes a syrupy fluid which in a 5-per-cent. dilution is used for disinfecting linen and the hands. Dejecta may be disinfected by using a solution, which is said to be fatal to the micro-organisms of suppuration, anthrax, cholera, and enteric fever.