The effect of repeated administrations of 32 mgms. of atropine sulfate to 183 unselected mentally ill patients has been studied. There was one death in this series. One hundred and fifty-four of these cases have been statistically analysed. Five to six months following the termination of therapy the following was found:Sixteen percent of all patients were on convalescent status, markedly improved. Sixty percent of all neurotic patients were on convalescent status, markedly improved. Twenty percent of all catatonic schizophrenic patients were on convalescent status, markedly improved. Twenty-three percent of all manic-depressive patients, manic phase, were on convalescent status markedly improved. Eleven percent of all paranoid schizophrenic patients were on convalescent status, improved.It is apparent that toxic doses of atropine sulfate are necessary to be therapeutically effective. Further investigation into pharmacotoxic therapy with other drug agents appears to be a promising field for research.