SummaryThe effect on the clinical status of catabolic hemodialysis patients of I.V. essential amino-acids administered over 3 months at the end of each dialysis is assessed in an open clinical follow-up study of 10 patients; these patients showed a progressive deterioration of general condition and a progressive weight loss in the period before the start of the treatment. The study was undertaken in a hospital dialysis unit, with as main outcome measures body weight, hematocrit, a scoring index of general condition and degree of edema. In patients showing a progressive and consistent loss of body weight in the months preceding the study, after the first treatment month, body weight started to rise, increasing after 3 months from 56.2±2.3 to 58.6±2.4 kg (p<0.01). The hematocrit raised from 22.4±1.6 % up to 26.5±1.9 % (p<0.02).Over this period, only 2 liters of packed cells were administered, in contrast to an overall need of 13 liters in the preceding 6 months. Peripheral and/or pulmonary edema disappeared. A scoring index, of general condition, increased from 5.1±1.5 before the start of the study to 11.7±0.8 after 3 months (p<0.01).It is concluded that the parenteral administration of amino-acids in catabolic patients on chronic hemodialysis has a beneficial effect on general condition, and the balance of body fluid and body mass.