Human Sensitization After Large Amounts Of Horse Serum

That an individual injected with horse serum develop skin hypersensitiveness has been shown by the observations of Hamburger and Pollak (1), Michiels (2), Cowie (3) and especially by the studies of Longcope and Rackemann (4). The latter observed the occurence of skin reactions of the wheal and erythma type in serum treated patients during the first few weeks following serum administration. In their 15 tabualted cases the patients received from 7.5 to 360 cc. of horse serum. All developed positive reactions between the seventh and fiftieth day after the serum injection. Recently Hooker (5) has reported that 27 per cent of 96 individuals a previously negative reaction became positive after administration of toxin-antitoxin mixtures containing a total of about 0.01 cc. of horse serum. He also reports that he observed positive reactions six months to seventeen years (average eight years) following serum therapy. Park’s (6) observations confirm Hooker’s conclusions concerning the skin sensitizing effect of toxin-antitoxin injections.