GENERAL CONSIDERATIONS
Cooke1 discussed the protein derivatives histamine, proteose and nucleic acid as factors in allergy. He concluded his discussion of histamine with this statement: "... with regard to clinical studies, my results are not in accord with most of those reported. I find no unresponsive phase in urticaria [it has been assumed that if a spontaneous urticarial wheal appears in a certain area, it will not reappear in that area for thirty-six to forty-eight hours], no increase of tolerance to histamine, no clinical result in chronic urticaria and no evidence that histamine is increased in the blood during general allergic reactions." Regarding proteose, he expressed the belief that clinical sensitization to derivatives of the digestion of protein, at least to those in the proteose state, existed. Regarding nucleic acid he stated that in his clinic certain patients sensitive to ragweed had been tested with nucleic acid and positive reactions