A study has been made of possible inter-relationship between the plasma levels of vitamin A, retinol binding protein (RBP) prealbumin (PA), and biochemical parameters in 47 patients with end-stage renal failure maintained on regular dialysis treatment. The raised plasma concentrations of vitamin A, RBP and PA in patients were significantly different from those of normal controls. Plasma vitamin A levels were inversely correlated with Hct (r = -0.499), which was also significantly related to RBP/vitamin A ratio (r = 0.61). Plasma i-PTH and VLDL were inversely related to RBP/vitamin A and RBP/PA ratios. These findings suggest that raised plasma vitamin A levels in regular dialysis patients contribute to anemia and hypervitaminosis A toxicity. Vitamin A preparations should therefore not be given to patients on regular dialysis treatment.