URTICARIA

Urticaria is characterised by a particular form of lesion known as the wheal, which is a round, elongate or irregularly shaped, flat elevation of the skin due to a circumscribed tense edema of the corium. Wheals vary in size, some may be only as large as the head of a pin, others larger than the palm of the hand. To the touch they are moderately firm and cannot be made to disappear or pit on pressure. The color is pale pink or white except at the margin where there is a rosy areola. The wheals appear suddenly and disappear more gradually, persisting from a few minutes to several hours. They are usually accompanied by lively sensations of itching, tingling and burning. Frictional irritation of unaffected portions of the skin sometimes provokes the appearance of new wheals, and therefore efforts made to relieve the subjective symptoms by rubbing or scratching often aggravate the disease. When the cutaneous response to mechanical stimulation is very pronounced the condition is often described as *urticaria factitia* or *dermographia*. Occasionally the serous effusion passes beyond the stage of edema and elevates the epidermis in the form of blebs, urticaria bullosa. The lesions may be few or numerous, discrete or confluent, they are nearly always ephemeral, and the disease itself in the majority of instances is acute and lasts from only a few hours to several days. In the comparatively rare chronic cases the disease is prolonged for weeks or even months by the continuous outcropping of new wheals, and the patient's general health often suffers from the constant distress caused by the itching. This distribution of the lesions is irregular and there is no predilection for any particular re-

gion unless it is where the pressure of clothes or similar influences evoke a more profuse efflorescence. Children are particularly liable to the disease. The factors which will call forth an urticarial rash in those who are predisposed are very numerous and include such external causes as the irritation of skin parasites, the bites of insects, contact with some jelly fish and nettles, and even sudden change of temperature. Many patients discover that certain articles of diet are responsible for outbreaks. Among those most often mentioned are strawberries, cucumbers, all kinds of sea food, pork, cheese, oatmeal, confectionery and pastry, and also vinegar and sour wines. Certain diseases are apt to be complicated by urticaria, the acute infections, especially articular rheumatism, diabetes, nephritis, and icterus from any cause and very commonly, particularly in children, gastric and intestinal disorders, such as constipation, dyspepsia, worms, or presence in the alimentary canal of indigestible masses of food. Drug rashes caused by quinin, salicylates, opium and its alkaloids, chloral, iodids, santonin, balsams and turpentines, and antitoxins may be urticarial in form.

**TREATMENT:** A brisk catharsis followed by a very simple or milk diet for several days will relieve most patients. In many cases the coagulation time of the blood has been found increased and for that reason calcium lactate in twenty grain doses t. i. d., is recommended and often seems to help, as also sodium bicarbonate or potassium acetate, one drachm t. i. d. The patients should avoid warm clothing, warm rooms, and coarse underwear. Externally a lotion containing 1 or 2% carbolic acid will relieve the itching.

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