The histamine-induced skin reaction in schizophrenic and normal subjects

Most published data on histamine skin tests on schizophrenic patients show them to be insensitive relative to normals or other psychotic patients. However, experimental conditions have varied and in most cases only a single dose of histamine was used. We have compared 13 volunteer controls and 16 paranoid schizophrenics; each subject was injected intradermally with histamine, 10, 20, and 50 microgram, doses predetermined in volunteers to give a dose-response curve. Wheal and flare were measured at 10 and 20 minutes, intervals near the time of maximum flare. We found no statistically significant differences between normal controls and schizophrenic patients.