Determining drug sensitivity; use of the gel diffusion method.

A study was carried out to determine whether the double diffusion gel test when applied to the serum of patients with clear-cut penicillin reactions of various types, might be useful for demonstrating the presence of precipitating antibody. Results did not demonstrate the antibody.The difference in results with this test obtained by various workers was not explained by the observations in this study. Other approaches to determination of the mechanism of the penicillin reaction are discussed, and it is noted that the hemagglutination test, newly applied to the penicillin reaction problem, may be useful after further investigation.