22 chloramphenicol allergics, 10 penicillin allergics and 6 patients with a chromate eczema as well as altogether 34 non-allergic control persons with healthy skin were examined according to the skin chamber method. After addition of the adequate antigen (chloramphenicol, penicillin, ammonium bichromate) into one of the two simultaneously applied skin chambers in sensitized persons an inhibition of the leucocyte migration in the antigen chamber develops. The polymorphonuclear neutrophilic granulocytes mobilised into the inflammation field were regarded as indicator cells. 5 chloramphenicol allergics with eczematous skin abnormalities and all control persons were negative. The investigation method is simply to be performed and therefore it is particularly suitable for clinical routine work.