Abstract
PREVIOUS LITERATURE When histamine is brought in contact with the minute vessels of the skin, a marked vasodilatation occurs in the normal individual. This reaction has been described by Eppinger1 and by Sollmann and Pilcher2 in man. The voluminous literature on the action of histamine on vessels was critically reviewed by Hess. While the minute vessels, capillaries, smallest arterioles and venules dilate under the action of histamine, there is a vasoconstrictor action on the larger arteries and veins.3 The response of the vessels of the skin to histamine has been extensively studied by Sir Thomas Lewis,4 who described a triple response to histamine. When a solution of histamine acid phosphate in a concentration of 1: 1,000 was placed on the skin and punctured into the epidermis with a fine hypodermic needle, the following reactions resulted: (1) a purplish spot around the puncture, (2) a wheal that