Serum Digoxin Levels in Chronic Renal Failure The interpretation of serum digoxin level in chronic renal failure could be difficult due to endogeneous digoxin like substances. The aim of this study was to determine the effect of different stages of renal failure on serum digoxin levels. Sixty-one patients with chronic renal failure were included in the study and were separated into two groups (Group I: patients on digoxin therapy, Group II: patients without digoxin therapy). Each group was further divided into three subgroups depending on the patients' creatinine clearances (a: >50, b: 10-50, c: 50, 10-50, 10 cm3/dk olan Grup la ve Ib'deki hastaların serum digoksin düzeyleri Grup İla ve Ilb'deki hastalara göre anlamlı olarak fazla (p10 cm3/dk olan grupta