PSORIASIS (from the Greek word psora, which signifies a cutaneous eruption, sup posed by some to be the itch) is now employed to signify a disease characterized by slight elevations of the surface of the skin covered with whitish scales. There are vari ous forms of this disorder, such as P. guttata (which is the simplest kind, and derives its specific name from the scales not coalescing, but remaining distinct, like isolated drops of water on the skin); P. (Vasa, when the disease spreads over large portions of the skin, and often renders the patient hideous to look at, the scaly incrustations being often interspersed with bleeding cracks and fissures in all directions; P. inveterate, which is merely the severest phase of the preceding form, and occurs chiefly in itaed persons of broken-down constitution; and P. gyrate, a rare form, in which the disease occurs in narrow stripes or rings. The causes of psoriasis are very obscure.. It is certainly not contagious, but there appears to be in some families an hereditary tendency to it. It is occasionally associated with gout and rheumatism. Persons of both sexes, of all ages, and of all conditions of life, are liable to it, although it is more common in middle and advanced life than in childhood. The treatment varies with the condition of the patient.
A middle-aged, vigorous patient should be purged two or three times a week with sul phate of magnesia, should be restricted in his diet to vegetables and milk, should be debarred from all stimulants, and should take a warm bath daily. The internal remedies of most repute for this disease are-1. Decoction of dulcamara, front half a pint at first to a pint being taken in divided doses through the day; 2. Liquor potasste, in doses of from half a dram to a drain, three times a day, in a glass of milk or beer; 3. Liquor arsenicals, in doses of from three to four minims, three times a day, to be taken after meals; 4. Iodide of potassium, in five-grain doses, three times a day; and 5. Pitch pills. In very inveterate cases, tar ointment, first diluted with lard, or a weak ointment of iodide of sulphur, should be'applied locally; but these should not be tried unless internal treatment fails.