1. A method for the direct determination of GSH in leukocytes is described. Treatment with alkali (0.5 M. NaOH) effects complete solution of the white cells and after deproteinization (5 per cent HPO3), the GSH is determined by the sensitive "alloxan 305" procedure. Control studies showed that under the conditions of the test, GSH is not affected by the alkali and no splitting of soluble minus SH from protein occurs.
2. Using this method, the amount of reduced glutathione content of normal leukocytes was found to be 5.2 ± 1 mg, per 1010 WBC.
3. No differences from normal levels were detected for the leukocytic GSH of patients with mental disease and those susceptible to agranulocytosis. Incubation of whole blood with the drug which caused agranulocytosis had no effect upon the GSH content of leukocytes.