IN THE two years that have elapsed since the review of the literature of 1944 and 1945 was presented1 several advances in knowledge have been made. The first is a dramatic advance. It concerns the antihistaminic drugs which late in 1945 were hailed as a possible panacea for allergic diseases of every kind. A large number of papers have described the many aspects of it. The second is more clinical and practical; it concerns the psychosomatic factors which are being recognized more and more in the cause of asthma. The third is the new development in the understanding of the pathologic aspects of asthma and kindred states and their relation to similar lesions produced by a similar mechanism in other diseases. Finally, the treatment of patients has been improved by the method of administering drugs directly to the nasal and bronchial mucosa in the form of a fine spray, or