✓ Twenty patients seriously ill following subtotal excision of brain tumors were given unusually large doses of Decadron to restrain peritumoral edema. The prompt clinical effect was strikingly favorable in 11. The dosage of Decadron above which no additional anti-edema effect occurs must be established for each individual patient. No significant complications occurred under dosages ranging from 32 to 96 mg/day. Brain scintiscans performed after rapid clinical improvement in five cases showed no change.