IN A PREVIOUS communication,1our clinical experience with gantrisin,®a new sulfonamide with the formula 3,4-dimethy1-5-sulfanilamido-isoxazole, was reported. Its use as the sole bacteriostatic agent in 53 patients with various infections and in combination with antibiotics in 38 others was reported, the entire series including practically all the conditions for which sulfonamides are currently used. The results on the whole were satisfactory. In the series of 91 patients reactions of some type occurred in 9, anorexia in 1, nausea in 5, vomiting in 2, headache in 1, a generalized eruption in 1 and crystalluria in 2. No hematuria or renal blocking was noted. More than 100 patients have been treated since that report with approximately the same results. Since many of the conditions for which sulfonamides are commonly prescribed are self limiting, we felt that a separate and somewhat more detailed report of our results in bacterial meningitis—a