The use of metrazol was discontinued because of the complication of fractures although this complication can be avoided by using curare. Metrazol is most efficacious in the affective disorders (manic-depressive psychoses; involutional melancholia and agitated depression). Treated with metrazol forty per cent recovered and forty per cent were improved. In the schizophrenic disorders seventeen per cent showed social recovery and fifty-five per cent remained unchanged. All of these patients received psychotherapy, and milieu therapy. Tables are given to show the results of other workers in 562 cases of affective disorders and 7369 cases of schizophrenic disorders.