ADRENOCORTICAL steroids are known to cause eosinophenia and lymphopenia, but information as to their effects on other white blood cells is limited.1,2 Even though moderate neutrophilic leukocytosis has been reported in adults receiving steroids, there is no information regarding their effects in children, and no data available on changes in monocyte counts.1-3 This paper reports the effects of large doses of steroids on the circulating white blood cells in children. Materials and Methods Ten patients suffering from nonhematological diseases, who received large doses of prednisone, prednisolone, or triamcinolone (hereafter referred to as steroids), were studied by serial white cell counts. None of the patients revealed any evidence of clinical infection during the period of study. Their description, diagnoses, and dosage of steroids are given in the Table. Five children were given steroids in large doses for two weeks, two children for three to six weeks, and three children