| Rx. | Olei myristicæ exp., | fluidrachm ij; |
| Alcoholis, Spiritus lavandulæ, aa. | fluidounce ij. M. |
Carbolic acid may be used as follows:
| Rx. | Acidi carbolici cryst., | drachm ij; |
| Alcoholis, | fluidounce iij; | |
| Olei ricini, | fluidrachm iv; | |
| Spts. rosmarini, | fluidrachm iv. M. |
Aqua ammoniæ may sometimes be employed with benefit, as in the formula recommended by Wilson:
| Rx. | Olei amygdalæ dulc., Aquæ ammoniæ fort., aa. | fluidounce ss; |
| Spiritus rosmarini, | fluidounce ij; | |
| Olei limonis, | fluidrachm ss. M. |
Blistering the affected areas by means of a cantharidal vesicating fluid, frequently repeated, sometimes proves of advantage. Friction with oil of turpentine once or twice daily may in some cases be practised with benefit; when the skin becomes sensitive it should be discontinued for a few days. Chrysarobin in ointment, 5 to 15 per cent. strength, is an active irritant which may be cautiously employed. Oleate of mercury, 10 to 30 per cent. strength, rubbed in once or twice daily, is useful in some cases, and the same may be said of the other mercurial ointments, such as citrine and white precipitate ointments. Electricity sometimes proves of service, and may be tried in obstinate cases.
Atrophia Pilorum Propria.
Atrophia pilorum propria, or atrophy of the hair, may be either symptomatic or idiopathic. As a symptomatic affection it is seen as a result of such diseases of the scalp as seborrhoea and the parasitic affections, and also following various constitutional diseases, such as syphilis and fevers, in consequence of impaired nutrition. The hairs become dry, brittle, atrophied, and exhibit a marked disposition to split up. Idiopathic atrophy of the hair is characterized in one of its forms (fragilitas crinium) by a brittle state of the hair-shaft, an irregular and uneven formation of its structure, and a tendency to separate into its filaments. It is seen about the scalp and beard, and may be slight or markedly developed. A somewhat similar condition of the hair of the beard has been described (Duhring), in which the bulb is atrophied and the shaft split up, fission taking place within the follicles, causing irritation of the skin. Another form (trichorexis nodosa) of the idiopathic affection is characterized by shining, semi-transparent, rounded swellings of the hair-shaft, seen usually upon the beard and moustache. At first sight they look not unlike the ova of pediculi; one or several may be present upon a single hair. Upon close inspection they are seen to be localized swellings of the hair-structure. At these points the hairs readily break off, leaving a brush-like end; if many of these are present, which is usually the case, they give the impression that the hair has been singed. The medullary as well as the cortical substance, as determined by microscopical examination, is swollen, and in consequence of the swelling of the medullary portion the cortex is burst and split into filaments. In regard to the cause of idiopathic atrophy of the hair nothing is known, and but little can be done in the way of treatment. Shaving and cutting the hair have exceptionally been followed by a normal growth.
Atrophia Unguis.
Atrophy of the nail is commonly an acquired affection. It is characterized by deficient development or growth of the nail-substance, as shown by a thin, brittle, soft, crumbly or worm-eaten condition. The nail may be pale, opaque or dark in color. It may occur in consequence of injury or disease of the nerves of the part, or as a result of some general disease, as syphilis, or from general debility. Eczema, psoriasis, and allied diseases, which may be productive of hypertrophy of the nails, may also cause atrophic changes. Treatment of atrophy of the nail depends upon the cause. In simple atrophy, and also in that due to eczema and psoriasis, arsenic is of value.