Hypothesis 1: A reduction in side effects is achieved with monitoring glucocorticoid treatment by using the Glucocorticoid Toxicity Index (GTI) in patients using glucocorticoids. Hypothesis 2: Monitoring treatment by using GTI in patients using glucocorticoids causes a decrease in glucocorticoid toxicity and an increase in the quality of life of patients. Hypothesis 3: With the involvement of the clinical pharmacist in the multidisciplinary team in patients using glucocorticoids, the drug-related problems of the patients are detected and prevented. The aim of this study was to evaluate the glucocorticoid treatment of patients with RA, SLE and vasculitis treated with glucocorticoids prospectively by a multidisciplinary team with GTI. In addition, it was aimed to identify and prevent drug-related problems by reviewing all drugs used in these patients by the clinical pharmacist.