A clinical and laboratory analyrsis of the dYnamlc change of plasma cortisol level in tw0 groups of chiIdren with neDhrotic syndrome has been made-a combined treatment group and a control group. The former was given long-term large dosage prednisone co rnbined with "Z1 Yin Jiailg Huo" and "Wen Bu Shen Yang" drugs, while the latter received no traditionaI medieine during pred-nisone administration The aim of the present study is to find Out whether tra-ditional medicines can protect the adrenal cortex. and antagonize the negative feed-back action Of exogenous steroid, thereby providing a theoretical and labora tory basis for dinical use of traditional medicines in reducing severe side effects of large dosage of steroid. Our results show: 1. Large dosage prednisone, either given daily in diVided doses or once every other day, can significantly suppress the adrenocortical activity, and the suppressive action decreases along with taper-ing off of the dosage of prednisone. 2. "Wen Bu Shen Yang" drugs can remark ably protect the adrenal eortex and antagonize the negative feed-back action of exogenous glucocorticosteroid. 3. "Zi Yin Jiang Huo" drugs possess no significant influence on plasma cortisoI level during long-term large dosage steroid therapy.