SINCE the time of Bateman, who accurately described lichen urticatus, there has been controversy about the nature and pathogenesis of this disorder. In successive periods of dermatologic history new ideas have developed about this disease, reflecting the thoughts and subject matters current at the moment. Thus, at one period, foods and bowel disturbances were said to be causative, in harmony with the emphasis placed on intestinal putrefactions and toxemias. At present lichen urticatus is mostly thought of as a form of urticaria, in keeping with the keen awareness of the phenomena of allergy, and is so classified in the textbooks.
There has been so much written on lichen urticatus that there would seem to be little excuse for still further overtaxing what has been for the most part theoretic discussion. Only new evidence can be an adequate reason for reopening the subject. The recent development and use of the antihistaminic