To the Editor:— The analgesic, sedative, and anticonvulsive properties of Tridione, Abbott (3,5,5-Trimethyloxazolidine-2,4-dione), are at present undergoing experimental and clinical investigation (J. Pharmacol. & Exper. Therap.81:402 [Aug.] 1944). To date no untoward reactions have been reported with the exception of a rash in 2 cases and an occasional case of blurring of vision or changes in color perception (believed to be functional, completely reversible after discontinuance of the drug, and showing no optic nerve damage in experimental animals). The following neutropenic response has not previously been noted: A white woman aged 25, seen in the dispensary May 6, 1946, complained of submandibular tenderness and swelling. The parotid glands were not tender or swollen, and Stensen's ducts were not inflamed. The temperature was normal. Her gums were in very poor condition. Oral hygiene was poor. No further physical findings were discovered. The patient was married and had one child.